Lamm C, Nusbaum HC, Meltzoff AN, Decety J.
PLoS ONE, 2, e1292
BACKGROUND: Recent neuroscientific evidence suggests that empathy for pain activates similar neural representations as the first-hand experience of pain. However, empathy is not an all-or-none phenomenon but it is strongly malleable by interpersonal, intrapersonal and situational factors. This study investigated how two different top-down mechanisms - attention and cognitive appraisal - affect the perception of pain in others and its neural underpinnings. METHODOLOGY/PRINCIPAL FINDINGS: We performed one behavioral (N = 23) and two functional magnetic resonance imaging (fMRI) experiments (N = 18). In the first fMRI experiment, participants watched photographs displaying painful needle injections, and were asked to evaluate either the sensory or the affective consequences of these injections. The role of cognitive appraisal was examined in a second fMRI experiment in which participants watched injections that only appeared to be painful as they were performed on an anesthetized hand. Perceiving pain in others activated the affective-motivational and sensory-discriminative aspects of the pain matrix. Activity in the somatosensory areas was specifically enhanced when participants evaluated the sensory consequences of pain. Perceiving non-painful injections into the anesthetized hand also led to signal increase in large parts of the pain matrix, suggesting an automatic affective response to the putatively harmful stimulus. This automatic response was modulated by areas involved in self/other distinction and valence attribution - including the temporo-parietal junction and medial orbitofrontal cortex. CONCLUSIONS/SIGNIFICANCE: Our findings elucidate how top-down control mechanisms and automatic bottom-up processes interact to generate and modulate other-oriented responses. They stress the role of cognitive processing in empathy, and shed light on how emotional and bodily awareness enable us to evaluate the sensory and affective states of others.
Thursday, December 27, 2007
ARTICLE UPDATE - Remembering the good times: neural correlates of affect regulation.
Cooney RE, Joormann J, Atlas LY, Eugène F, Gotlib IH.
Neuroreport, 18, 1171-1174
The ability to regulate one's mood state effectively is critical to emotional and physical health. Recent investigations have sought to delineate the neural mechanisms by which individuals regulate mood states and emotions, positing a critical role of a dorsal system that includes the dorsolateral prefrontal cortex and anterior cingulate. This study extended these efforts by examining the neural correlates of retrieving positive autobiographical memories while experiencing a negative mood state in a sample of healthy female adults. We demonstrated that mood-incongruent recall is associated with activation in ventrolateral and ventromedial prefrontal cortices (including orbitofrontal cortex and subgenual cingulate). These findings suggest that mood-incongruent recall differs from other affect regulation strategies by influencing mood through a ventral regulatory network.
Neuroreport, 18, 1171-1174
The ability to regulate one's mood state effectively is critical to emotional and physical health. Recent investigations have sought to delineate the neural mechanisms by which individuals regulate mood states and emotions, positing a critical role of a dorsal system that includes the dorsolateral prefrontal cortex and anterior cingulate. This study extended these efforts by examining the neural correlates of retrieving positive autobiographical memories while experiencing a negative mood state in a sample of healthy female adults. We demonstrated that mood-incongruent recall is associated with activation in ventrolateral and ventromedial prefrontal cortices (including orbitofrontal cortex and subgenual cingulate). These findings suggest that mood-incongruent recall differs from other affect regulation strategies by influencing mood through a ventral regulatory network.
Thursday, December 20, 2007
ARTICLE UPDATE - The effects of nonconsciously priming emotion concepts on behavior.
Zemack-Rugar Y, Bettman JR, Fitzsimons GJ.
Journal of Personality and Social Psychology, 93, 927-939
Current empirical evidence regarding nonconsciously priming emotion concepts is limited to positively versus negatively valenced affect. This article demonstrates that specific, equally valenced emotion concepts can be nonconsciously activated, remain inaccessible to conscious awareness, and still affect behavior in an emotion-specific fashion. In Experiment 1A, participants subliminally primed with guilty emotion adjectives showed lower indulgence than did participants subliminally primed with sad emotion adjectives; even after the addition of a 5-min time delay, these results were replicated in Experiment 1B. Participants in the different priming conditions showed no differences in their subjective emotion ratings and were unaware of the emotion prime or concept activation. Experiments 2A and 2B replicated these findings using a helping measure, demonstrating that individuals primed with guilt adjectives show more helping than do individuals primed with sadness adjectives. In all studies, effects were moderated by individuals' specific emotion-response habits and characteristics.
Journal of Personality and Social Psychology, 93, 927-939
Current empirical evidence regarding nonconsciously priming emotion concepts is limited to positively versus negatively valenced affect. This article demonstrates that specific, equally valenced emotion concepts can be nonconsciously activated, remain inaccessible to conscious awareness, and still affect behavior in an emotion-specific fashion. In Experiment 1A, participants subliminally primed with guilty emotion adjectives showed lower indulgence than did participants subliminally primed with sad emotion adjectives; even after the addition of a 5-min time delay, these results were replicated in Experiment 1B. Participants in the different priming conditions showed no differences in their subjective emotion ratings and were unaware of the emotion prime or concept activation. Experiments 2A and 2B replicated these findings using a helping measure, demonstrating that individuals primed with guilt adjectives show more helping than do individuals primed with sadness adjectives. In all studies, effects were moderated by individuals' specific emotion-response habits and characteristics.
ARTICLE UPDATE - Predictors of amygdala activation during the processing of emotional stimuli: A meta-analysis of 385 PET and fMRI studies.
Costafreda SG, Brammer MJ, David AS, Fu CH.
Brain Research Review, in press (Note that this link will direct you to download this article in pdf format. So it might not work for everyone)
Although amygdala activity has been purported to be modulated by affective and non-affective factors, considerable controversy remains on its precise functional nature. We conducted a meta-analysis of 385 functional neuroimaging studies of emotional processing, examining the effects of experimental characteristics on the probability of detecting amygdala activity. All emotional stimuli were associated with higher probability of amygdala activity than neutral stimuli. Comparable effects were observed for most negative and positive emotions, however there was a higher probability of activation for fear and disgust relative to happiness. The level of attentional processing affected amygdala activity, as passive processing was associated with a higher probability of activation than active task instructions. Gustatory-olfactory and visual stimulus modalities increased the probability of activation relative to internal stimuli. Aversive learning increased the probability of amygdala activation as well. There was some evidence of hemispheric specialization with a relative left-lateralization for stimuli containing language and a relative right-lateralization for masked stimuli. Methodological variables, such as type of analysis and magnet strength, were also independent predictors of amygdala activation.
Brain Research Review, in press (Note that this link will direct you to download this article in pdf format. So it might not work for everyone)
Although amygdala activity has been purported to be modulated by affective and non-affective factors, considerable controversy remains on its precise functional nature. We conducted a meta-analysis of 385 functional neuroimaging studies of emotional processing, examining the effects of experimental characteristics on the probability of detecting amygdala activity. All emotional stimuli were associated with higher probability of amygdala activity than neutral stimuli. Comparable effects were observed for most negative and positive emotions, however there was a higher probability of activation for fear and disgust relative to happiness. The level of attentional processing affected amygdala activity, as passive processing was associated with a higher probability of activation than active task instructions. Gustatory-olfactory and visual stimulus modalities increased the probability of activation relative to internal stimuli. Aversive learning increased the probability of amygdala activation as well. There was some evidence of hemispheric specialization with a relative left-lateralization for stimuli containing language and a relative right-lateralization for masked stimuli. Methodological variables, such as type of analysis and magnet strength, were also independent predictors of amygdala activation.
ARTICLE UPDATE - Neural response to emotional pictures is unaffected by concurrent task difficulty: An event-related potential study.
Hajcak G, Dunning JP, Foti D.
Behavioural Neuroscience, 121, 1156-1162
The late positive potential (LPP) is an event-related potential that is enhanced when viewing arousing (pleasant and unpleasant) pictures compared to neutral pictures. The affective modulation of the LPP is believed to reflect the increased attention to, and perceptual processing of, emotional stimuli. The present study examined whether concurrent task difficulty (performing mathematics) would modulate the LPP while participants viewed emotionally arousing stimuli. Results indicated that the LPP was larger following pleasant and unpleasant stimuli than it was following neutral stimuli; moreover, the magnitude of this increase was not influenced by concurrent task difficulty. This finding suggests that the affective modulation of neural activity during picture viewing is relatively automatic and is insusceptible to competing task demands. Results are further discussed in terms of the LPP's role in motivated attention and implications for research on emotion regulation.
Behavioural Neuroscience, 121, 1156-1162
The late positive potential (LPP) is an event-related potential that is enhanced when viewing arousing (pleasant and unpleasant) pictures compared to neutral pictures. The affective modulation of the LPP is believed to reflect the increased attention to, and perceptual processing of, emotional stimuli. The present study examined whether concurrent task difficulty (performing mathematics) would modulate the LPP while participants viewed emotionally arousing stimuli. Results indicated that the LPP was larger following pleasant and unpleasant stimuli than it was following neutral stimuli; moreover, the magnitude of this increase was not influenced by concurrent task difficulty. This finding suggests that the affective modulation of neural activity during picture viewing is relatively automatic and is insusceptible to competing task demands. Results are further discussed in terms of the LPP's role in motivated attention and implications for research on emotion regulation.
Friday, December 14, 2007
ARTICLE UPDATE - Affective picture perception: Emotion, context, and the late positive potential.
Pastor MC, Bradley MM, Löw A, Versace F, Moltó J, Lang PJ.
Brain Research, in press
Event-related potentials (ERP) were measured when pleasant, neutral or unpleasant pictures were presented in the context of similarly valenced stimuli, and compared to ERPs elicited when the same pictures were viewed in an intermixed context. An early ERP component (150-300 ms) measured over occipital and fronto-central sensors was specific to viewing pleasant pictures and was not affected by presentation context. Replicating previous studies, emotional pictures prompted a larger late positive potential (LPP, 400-700 ms) and a larger positive slow wave (1-6 s) over centro-parietal sensors that also did not differ by presentation context. On the other hand, ERPs elicited when viewing neutral pictures varied as a function of context, eliciting somewhat larger LPPs when presented in blocks, and prompting smaller slow waves over occipital sensors. Taken together, the data indicate that emotional pictures prompt increased attention and orienting that is unaffected by its context of presentation, whereas neutral pictures are more vulnerable to context manipulations.
Brain Research, in press
Event-related potentials (ERP) were measured when pleasant, neutral or unpleasant pictures were presented in the context of similarly valenced stimuli, and compared to ERPs elicited when the same pictures were viewed in an intermixed context. An early ERP component (150-300 ms) measured over occipital and fronto-central sensors was specific to viewing pleasant pictures and was not affected by presentation context. Replicating previous studies, emotional pictures prompted a larger late positive potential (LPP, 400-700 ms) and a larger positive slow wave (1-6 s) over centro-parietal sensors that also did not differ by presentation context. On the other hand, ERPs elicited when viewing neutral pictures varied as a function of context, eliciting somewhat larger LPPs when presented in blocks, and prompting smaller slow waves over occipital sensors. Taken together, the data indicate that emotional pictures prompt increased attention and orienting that is unaffected by its context of presentation, whereas neutral pictures are more vulnerable to context manipulations.
ARTICLE UPDATE - Simultaneous recording of EEG and facial muscle reactions during spontaneous emotional mimicry.
Achaibou A, Pourtois G, Schwartz S, Vuilleumier P.
Neuropsychologia, in press
The perception of emotional facial expressions induces covert imitation in emotion-specific muscles of the perceiver's face. Neural processes involved in these spontaneous facial reactions remain largely unknown. Here we concurrently recorded EEG and facial EMG in 15 participants watching short movie clips displaying either happy or angry facial expressions. EMG activity was recorded for the zygomaticus major (ZM) that elevates the lips during a smile, and the corrugator supercillii (CS) that knits the eyebrows during a frown. We found increased EMG activity of CS in response to angry expressions, and enhanced EMG activity of ZM for happy expressions, replicating earlier EMG studies. More importantly, we found that the amplitude of an early visual evoked potential (right P1) was larger when ZM activity to happy faces was high, and when CS activity to angry faces was high, as compared to when muscle reactions were low. Conversely, the amplitude of right N170 component was smaller when the intensity of facial imitation was high. These combined EEG-EMG results suggest that early visual processing of face expression may determine the magnitude of subsequent facial imitation, with dissociable effects for P1 and N170. These findings are discussed against the classical dual-route model of face recognition.
Neuropsychologia, in press
The perception of emotional facial expressions induces covert imitation in emotion-specific muscles of the perceiver's face. Neural processes involved in these spontaneous facial reactions remain largely unknown. Here we concurrently recorded EEG and facial EMG in 15 participants watching short movie clips displaying either happy or angry facial expressions. EMG activity was recorded for the zygomaticus major (ZM) that elevates the lips during a smile, and the corrugator supercillii (CS) that knits the eyebrows during a frown. We found increased EMG activity of CS in response to angry expressions, and enhanced EMG activity of ZM for happy expressions, replicating earlier EMG studies. More importantly, we found that the amplitude of an early visual evoked potential (right P1) was larger when ZM activity to happy faces was high, and when CS activity to angry faces was high, as compared to when muscle reactions were low. Conversely, the amplitude of right N170 component was smaller when the intensity of facial imitation was high. These combined EEG-EMG results suggest that early visual processing of face expression may determine the magnitude of subsequent facial imitation, with dissociable effects for P1 and N170. These findings are discussed against the classical dual-route model of face recognition.
ARTICLE UPDATE - Serotoninergic regulation of emotional and behavioural control processes.
Cools R, Roberts AC, Robbins TW.
Trends in Cognitive Sciences, in press
5-Hydroxytryptamine (5-HT, serotonin) has long been implicated in a wide variety of emotional, cognitive and behavioural control processes. However, its precise contribution is still not well understood. Depletion of 5-HT enhances behavioural and brain responsiveness to punishment or other aversive signals, while disinhibiting previously rewarded but now punished behaviours. Findings suggest that 5-HT modulates the impact of punishment-related signals on learning and emotion (aversion), but also promotes response inhibition. Exaggerated aversive processing and deficient response inhibition could underlie distinct symptoms of a range of affective disorders, namely stress- or threat-vulnerability and compulsive behaviour, respectively. We review evidence from studies with human volunteers and experimental animals that begins to elucidate the neurobiological systems underlying these different effects.
Trends in Cognitive Sciences, in press
5-Hydroxytryptamine (5-HT, serotonin) has long been implicated in a wide variety of emotional, cognitive and behavioural control processes. However, its precise contribution is still not well understood. Depletion of 5-HT enhances behavioural and brain responsiveness to punishment or other aversive signals, while disinhibiting previously rewarded but now punished behaviours. Findings suggest that 5-HT modulates the impact of punishment-related signals on learning and emotion (aversion), but also promotes response inhibition. Exaggerated aversive processing and deficient response inhibition could underlie distinct symptoms of a range of affective disorders, namely stress- or threat-vulnerability and compulsive behaviour, respectively. We review evidence from studies with human volunteers and experimental animals that begins to elucidate the neurobiological systems underlying these different effects.
Friday, December 07, 2007
ARTICLE UPDATE- Subliminal smells can guide social preferences.
Li W, Moallem I, Paller KA, Gottfried JA.
Psychological Science, 18, 1044-1049
It is widely accepted that unconscious processes can modulate judgments and behavior, but do such influences affect one's daily interactions with other people? Given that olfactory information has relatively direct access to cortical and subcortical emotional circuits, we tested whether the affective content of subliminal odors alters social preferences. Participants rated the likeability of neutral faces after smelling pleasant, neutral, or unpleasant odors delivered below detection thresholds. Odor affect significantly shifted likeability ratings only for those participants lacking conscious awareness of the smells, as verified by chance-level trial-by-trial performance on an odor-detection task. Across participants, the magnitude of this priming effect decreased as sensitivity for odor detection increased. In contrast, heart rate responses tracked odor valence independently of odor awareness. These results indicate that social preferences are subject to influences from odors that escape awareness, whereas the availability of conscious odor information may disrupt such effects.
Psychological Science, 18, 1044-1049
It is widely accepted that unconscious processes can modulate judgments and behavior, but do such influences affect one's daily interactions with other people? Given that olfactory information has relatively direct access to cortical and subcortical emotional circuits, we tested whether the affective content of subliminal odors alters social preferences. Participants rated the likeability of neutral faces after smelling pleasant, neutral, or unpleasant odors delivered below detection thresholds. Odor affect significantly shifted likeability ratings only for those participants lacking conscious awareness of the smells, as verified by chance-level trial-by-trial performance on an odor-detection task. Across participants, the magnitude of this priming effect decreased as sensitivity for odor detection increased. In contrast, heart rate responses tracked odor valence independently of odor awareness. These results indicate that social preferences are subject to influences from odors that escape awareness, whereas the availability of conscious odor information may disrupt such effects.
ARTICLE UPDATE - An investigation of the cognitive and experiential features of intrusive memories in depression.
Williams AD, Moulds ML.
Memory, 15, 912-920
Intrusive autobiographical memories of negative past events are a clinical feature common to post-traumatic stress disorder (PTSD) and depression. Recent investigations provide increasing evidence that shared cognitive processes are linked to the maintenance of intrusive memories in both conditions. Still absent from the existing literature, however, is a systematic examination of the basic content and defining characteristics of intrusive memories in depression. This study sought to: (i) outline the content and features of intrusive memories in depression, and (ii) investigate whether intrusion characteristics linked to the persistence of intrusive memories in PTSD are also characteristic of intrusive memories in depression. A sample of undergraduate students (n=250) were interviewed and assessed for the presence of an intrusive memory in the past week, and completed a battery of measures that indexed cognitive and affective responses to the memory. Consistent with prediction, intrusive memories contained high levels of sensory experience and were marked by a sense of "nowness". In accord with studies with PTSD samples, sensory features accounted for unique variance in the prediction of depression severity, over and above that accounted for by intrusion frequency. This pattern of findings was replicated in a dysphoric (BDI-II>/=12) sub-sample of participants. Our results underscore the value of drawing on theoretical conceptualisations and empirical findings from the post-traumatic stress literature to extend our understanding of intrusive memories in depression.
Memory, 15, 912-920
Intrusive autobiographical memories of negative past events are a clinical feature common to post-traumatic stress disorder (PTSD) and depression. Recent investigations provide increasing evidence that shared cognitive processes are linked to the maintenance of intrusive memories in both conditions. Still absent from the existing literature, however, is a systematic examination of the basic content and defining characteristics of intrusive memories in depression. This study sought to: (i) outline the content and features of intrusive memories in depression, and (ii) investigate whether intrusion characteristics linked to the persistence of intrusive memories in PTSD are also characteristic of intrusive memories in depression. A sample of undergraduate students (n=250) were interviewed and assessed for the presence of an intrusive memory in the past week, and completed a battery of measures that indexed cognitive and affective responses to the memory. Consistent with prediction, intrusive memories contained high levels of sensory experience and were marked by a sense of "nowness". In accord with studies with PTSD samples, sensory features accounted for unique variance in the prediction of depression severity, over and above that accounted for by intrusion frequency. This pattern of findings was replicated in a dysphoric (BDI-II>/=12) sub-sample of participants. Our results underscore the value of drawing on theoretical conceptualisations and empirical findings from the post-traumatic stress literature to extend our understanding of intrusive memories in depression.
ARTICLE UPDATE - Under what conditions can human affective conditioning occur without contingency awareness? Test of the evaluative conditioning parad
Dawson ME, Rissling AJ, Schell AM, Wilcox R.
Emotion, 7, 755-766
The role of conscious cognitive processes in human affective conditioning remains controversial, with several theories arguing that such conditioning can occur without awareness of the conditioned stimulus (CS)-unconditioned stimulus (UCS) contingency. One specific type of affective conditioning in which unaware conditioning is said to occur is "evaluative conditioning." The present experiment tested the role of contingency awareness by embedding an evaluative conditioning paradigm in a distracting masking task while obtaining, in addition to subjective ratings of affect, both psychophysiological (skin conductance and startle eyeblink) and indirect behavioral (affective priming) measures of conditioning, along with a trial-by-trial measure of awareness from 55 college student participants. Aware participants showed conditioning with all of the measures; unaware participants failed to show conditioning with all measures. The behavioral, neurophysiological, and therapeutic implications of these findings are discussed.
Emotion, 7, 755-766
The role of conscious cognitive processes in human affective conditioning remains controversial, with several theories arguing that such conditioning can occur without awareness of the conditioned stimulus (CS)-unconditioned stimulus (UCS) contingency. One specific type of affective conditioning in which unaware conditioning is said to occur is "evaluative conditioning." The present experiment tested the role of contingency awareness by embedding an evaluative conditioning paradigm in a distracting masking task while obtaining, in addition to subjective ratings of affect, both psychophysiological (skin conductance and startle eyeblink) and indirect behavioral (affective priming) measures of conditioning, along with a trial-by-trial measure of awareness from 55 college student participants. Aware participants showed conditioning with all of the measures; unaware participants failed to show conditioning with all measures. The behavioral, neurophysiological, and therapeutic implications of these findings are discussed.
ARTICLE UPDATE - The influence of sad mood on cognition.
Chepenik LG, Cornew LA, Farah MJ.
Emotion, 7, 802-811
Neuroimaging has identified an overlapping network of brain regions whose activity is modulated by mood and cognition. Studies of depressed individuals have shown changes in perception, attention, memory, and executive functions. This suggests that mood has a pervasive effect on cognition. Direct evidence of the effect of sad mood on cognition is surprisingly limited, however. Published studies have generally addressed a single cognitive ability per study because the fleeting nature of laboratory-induced mood precludes extended testing, and robust findings are limited to mood effects on memory for emotional stimuli. In this study, sad mood was induced and prolonged, enabling the effects of mood to be assessed for an array of abilities, including those that share neural substrates with sad mood and those affected by depression. Sad mood affected memory for emotional words and facial emotion recognition, but not the other processes measured, with a significant nonuniformity of effect over tasks. These results are consistent with circumscribed effects of sad mood on certain emotion-related cognitive processes, but not on cognition more generally.
Emotion, 7, 802-811
Neuroimaging has identified an overlapping network of brain regions whose activity is modulated by mood and cognition. Studies of depressed individuals have shown changes in perception, attention, memory, and executive functions. This suggests that mood has a pervasive effect on cognition. Direct evidence of the effect of sad mood on cognition is surprisingly limited, however. Published studies have generally addressed a single cognitive ability per study because the fleeting nature of laboratory-induced mood precludes extended testing, and robust findings are limited to mood effects on memory for emotional stimuli. In this study, sad mood was induced and prolonged, enabling the effects of mood to be assessed for an array of abilities, including those that share neural substrates with sad mood and those affected by depression. Sad mood affected memory for emotional words and facial emotion recognition, but not the other processes measured, with a significant nonuniformity of effect over tasks. These results are consistent with circumscribed effects of sad mood on certain emotion-related cognitive processes, but not on cognition more generally.
ARTICLE UPDATE - Amygdala reactivity to masked negative faces is associated with automatic judgmental bias in major depression: a 3 T fMRI study.
Dannlowski U, Ohrmann P, Bauer J, Kugel H, Arolt V, Heindel W, Kersting A, Baune BT, Suslow T.
Journal of Psychiatry Neuroscience, in press
OBJECTIVE: In a previous study, we demonstrated that amygdala reactivity to masked negative facial emotions predicts negative judgmental bias in healthy subjects. In the present study, we extended the paradigm to a sample of 35 inpatients suffering from depression to investigate the effect of amygdala reactivity on automatic negative judgmental bias and clinical characteristics in depression. METHODS: Amygdala activity was recorded in response to masked displays of angry, sad and happy facial expressions by means of functional magnetic resonance imaging at 3 T. In a subsequent experiment, the patients performed an affective priming task that characterizes automatic emotion processing by investigating the biasing effect of subliminally presented emotional faces on evaluative ratings to subsequently presented neutral stimuli. RESULTS: Significant associations between (right) amygdala reactivity and automatic negative judgmental bias were replicated in our patient sample (r = -0.59, p < 0.001). Further, negatively biased evaluative processing was associated with severity and longer course of illness (r = -0.57, p = 0.001). CONCLUSION: Amygdala hyperactivity is a neural substrate of negatively biased automatic emotion processing that could be a determinant for a more severe disease course.
Journal of Psychiatry Neuroscience, in press
OBJECTIVE: In a previous study, we demonstrated that amygdala reactivity to masked negative facial emotions predicts negative judgmental bias in healthy subjects. In the present study, we extended the paradigm to a sample of 35 inpatients suffering from depression to investigate the effect of amygdala reactivity on automatic negative judgmental bias and clinical characteristics in depression. METHODS: Amygdala activity was recorded in response to masked displays of angry, sad and happy facial expressions by means of functional magnetic resonance imaging at 3 T. In a subsequent experiment, the patients performed an affective priming task that characterizes automatic emotion processing by investigating the biasing effect of subliminally presented emotional faces on evaluative ratings to subsequently presented neutral stimuli. RESULTS: Significant associations between (right) amygdala reactivity and automatic negative judgmental bias were replicated in our patient sample (r = -0.59, p < 0.001). Further, negatively biased evaluative processing was associated with severity and longer course of illness (r = -0.57, p = 0.001). CONCLUSION: Amygdala hyperactivity is a neural substrate of negatively biased automatic emotion processing that could be a determinant for a more severe disease course.
ARTICLE UPDATE - Relative left frontal activation to appetitive stimuli: Considering the role of individual differences.
Gable P, Harmon-Jones E.
Psychophysiology, in press
Experiments examining asymmetrical frontal activity in response to affective pictures have produced inconsistent results. These inconsistencies may have occurred because the pictorial stimuli may not have evoked strong emotional or motivational tendencies for all individuals. In the current study, participants were asked to indicate their liking for dessert and the time since they had last eaten to assess individual differences in emotion and motivation. Then, they were shown dessert pictures or neutral pictures while EEG activity was recorded. Results indicated that the individual differences predicted greater left than right frontal activity (inverse of the alpha power) within the first second as well as all 12 s of viewing of the dessert pictures.
Psychophysiology, in press
Experiments examining asymmetrical frontal activity in response to affective pictures have produced inconsistent results. These inconsistencies may have occurred because the pictorial stimuli may not have evoked strong emotional or motivational tendencies for all individuals. In the current study, participants were asked to indicate their liking for dessert and the time since they had last eaten to assess individual differences in emotion and motivation. Then, they were shown dessert pictures or neutral pictures while EEG activity was recorded. Results indicated that the individual differences predicted greater left than right frontal activity (inverse of the alpha power) within the first second as well as all 12 s of viewing of the dessert pictures.
Thursday, November 22, 2007
ARTICLE UPDATE - How emotions colour our perception of time.
Droit-Volet S, Meck WH.
Trends in Cognitive Sciences, in press (link not available yet)
Our sense of time is altered by our emotions to such an extent that time seems to fly when we are having fun and drags when we are bored. Recent studies using standardized emotional material provide a unique opportunity for understanding the neurocognitive mechanisms that underlie the effects of emotion on timing and time perception in the milliseconds-to-hours range. We outline how these new findings can be explained within the framework of internal-clock models and describe how emotional arousal and valence interact to produce both increases and decreases in attentional time sharing and clock speed. The study of time and emotion is at a crossroads, and we outline possible examples for future directions.
Trends in Cognitive Sciences, in press (link not available yet)
Our sense of time is altered by our emotions to such an extent that time seems to fly when we are having fun and drags when we are bored. Recent studies using standardized emotional material provide a unique opportunity for understanding the neurocognitive mechanisms that underlie the effects of emotion on timing and time perception in the milliseconds-to-hours range. We outline how these new findings can be explained within the framework of internal-clock models and describe how emotional arousal and valence interact to produce both increases and decreases in attentional time sharing and clock speed. The study of time and emotion is at a crossroads, and we outline possible examples for future directions.
Monday, November 19, 2007
ARTICLE UPDATE - Neural mechanisms mediating optimism bias
Tali Sharot, Alison M. Riccardi, Candace M. Raio & Elizabeth A. Phelps
Nature, 450, 102-105
Humans expect positive events in the future even when there is no evidence to support such expectations. For example, people expect to live longer and be healthier than average, they underestimate their likelihood of getting a divorce, and overestimate their prospects for success on the job market. We examined how the brain generates this pervasive optimism bias. Here we report that this tendency was related specifically to enhanced activation in the amygdala and in the rostral anterior cingulate cortex when imagining positive future events relative to negative ones, suggesting a key role for areas involved in monitoring emotional salience in mediating the optimism bias. These are the same regions that show irregularities in depression, which has been related to pessimism. Across individuals, activity in the rostral anterior cingulate cortex was correlated with trait optimism. The current study highlights how the brain may generate the tendency to engage in the projection of positive future events, suggesting that the effective integration and regulation of emotional and autobiographical information supports the projection of positive future events in healthy individuals, and is related to optimism.
Nature, 450, 102-105
Humans expect positive events in the future even when there is no evidence to support such expectations. For example, people expect to live longer and be healthier than average, they underestimate their likelihood of getting a divorce, and overestimate their prospects for success on the job market. We examined how the brain generates this pervasive optimism bias. Here we report that this tendency was related specifically to enhanced activation in the amygdala and in the rostral anterior cingulate cortex when imagining positive future events relative to negative ones, suggesting a key role for areas involved in monitoring emotional salience in mediating the optimism bias. These are the same regions that show irregularities in depression, which has been related to pessimism. Across individuals, activity in the rostral anterior cingulate cortex was correlated with trait optimism. The current study highlights how the brain may generate the tendency to engage in the projection of positive future events, suggesting that the effective integration and regulation of emotional and autobiographical information supports the projection of positive future events in healthy individuals, and is related to optimism.
ARTICLE UPDATE - Happy and fearful emotion in cues and targets modulate event-related potential indices of gaze-directed attentional orienting
Harlan M. Fichtenholtz, Joseph B. Hopfinger, Reiko Graham, Jacqueline M. Detwiler and Kevin S. LaBar
Social Cognitive Affective Neuroscience, 2, 323-333
The goal of the present study was to characterize the effects of valence in facial cues and object targets on event-related potential (ERPs) indices of gaze-directed orienting. Participants were shown faces at fixation that concurrently displayed dynamic gaze shifts and expression changes from neutral to fearful or happy emotions. Emotionally-salient target objects subsequently appeared in the periphery and were spatially congruent or incongruent with the gaze direction. ERPs were time-locked to target presentation. Three sequential ERP components were modulated by happy emotion, indicating a progression from an expression effect to a gaze-by-expression interaction to a target emotion effect. These effects included larger P1 amplitude over contralateral occipital sites for targets following happy faces, larger centrally distributed N1 amplitude for targets following happy faces with leftward gaze, and faster P3 latency for positive targets. In addition, parietally distributed P3 amplitude was reduced for validly cued targets following fearful expressions. Results are consistent with accounts of attentional broadening and motivational approach by happy emotion, and facilitation of spatially directed attention in the presence of fearful cues. The findings have implications for understanding how socioemotional signals in faces interact with each other and with emotional features of objects in the environment to alter attentional processes.
Social Cognitive Affective Neuroscience, 2, 323-333
The goal of the present study was to characterize the effects of valence in facial cues and object targets on event-related potential (ERPs) indices of gaze-directed orienting. Participants were shown faces at fixation that concurrently displayed dynamic gaze shifts and expression changes from neutral to fearful or happy emotions. Emotionally-salient target objects subsequently appeared in the periphery and were spatially congruent or incongruent with the gaze direction. ERPs were time-locked to target presentation. Three sequential ERP components were modulated by happy emotion, indicating a progression from an expression effect to a gaze-by-expression interaction to a target emotion effect. These effects included larger P1 amplitude over contralateral occipital sites for targets following happy faces, larger centrally distributed N1 amplitude for targets following happy faces with leftward gaze, and faster P3 latency for positive targets. In addition, parietally distributed P3 amplitude was reduced for validly cued targets following fearful expressions. Results are consistent with accounts of attentional broadening and motivational approach by happy emotion, and facilitation of spatially directed attention in the presence of fearful cues. The findings have implications for understanding how socioemotional signals in faces interact with each other and with emotional features of objects in the environment to alter attentional processes.
ARTICLE UPDATE - Amygdala–frontal connectivity during emotion regulation
Sarah J. Banks, Kamryn T. Eddy, Mike Angstadt, Pradeep J. Nathan and K. Luan Phan
Social Cognitive and Affective Neuroscience, 2, 303-312
Successful control of affect partly depends on the capacity to modulate negative emotional responses through the use of cognitive strategies (i.e., reappraisal). Recent studies suggest the involvement of frontal cortical regions in the modulation of amygdala reactivity and the mediation of effective emotion regulation. However, within-subject inter-regional connectivity between amygdala and prefrontal cortex in the context of affect regulation is unknown. Here, using psychophysiological interaction analyses of functional magnetic resonance imaging data, we show that activity in specific areas of the frontal cortex (dorsolateral, dorsal medial, anterior cingulate, orbital) covaries with amygdala activity and that this functional connectivity is dependent on the reappraisal task. Moreover, strength of amygdala coupling with orbitofrontal cortex and dorsal medial prefrontal cortex predicts the extent of attenuation of negative affect following reappraisal. These findings highlight the importance of functional connectivity within limbic-frontal circuitry during emotion regulation.
Social Cognitive and Affective Neuroscience, 2, 303-312
Successful control of affect partly depends on the capacity to modulate negative emotional responses through the use of cognitive strategies (i.e., reappraisal). Recent studies suggest the involvement of frontal cortical regions in the modulation of amygdala reactivity and the mediation of effective emotion regulation. However, within-subject inter-regional connectivity between amygdala and prefrontal cortex in the context of affect regulation is unknown. Here, using psychophysiological interaction analyses of functional magnetic resonance imaging data, we show that activity in specific areas of the frontal cortex (dorsolateral, dorsal medial, anterior cingulate, orbital) covaries with amygdala activity and that this functional connectivity is dependent on the reappraisal task. Moreover, strength of amygdala coupling with orbitofrontal cortex and dorsal medial prefrontal cortex predicts the extent of attenuation of negative affect following reappraisal. These findings highlight the importance of functional connectivity within limbic-frontal circuitry during emotion regulation.
Thursday, November 15, 2007
ARTICLE UPDATE - Brain activation and defensive response mobilization during sustained exposure to phobia-related and other affective pictures in spid
Wendt J, Lotze M, Weike AI, Hosten N, Hamm AO.
Psychophysiology, in press
This study explored defensive response mobilization as well as fMRI responses during sustained exposure to phobia-relevant stimuli. To test the specificity of affective physiology and brain activation, neutral and other affective stimuli were included. Phobia-specific startle potentiation was maintained and autonomic responses even increased during sustained phobic stimulation. Viewing of spider pictures also resulted in increased activation of the amygdala in spider-phobic participants. This effect, however, was not fear specific because other affective materials evoked comparable signal strength in the amygdala. In contrast, insula activation was specifically increased during sustained phobic exposure in phobic volunteers. These data suggest that the activation of the amygdala in fMRI studies primarily indexes the detection of motivationally relevant stimuli whereas the insula might be more specifically linked to defensive response mobilization.
Psychophysiology, in press
This study explored defensive response mobilization as well as fMRI responses during sustained exposure to phobia-relevant stimuli. To test the specificity of affective physiology and brain activation, neutral and other affective stimuli were included. Phobia-specific startle potentiation was maintained and autonomic responses even increased during sustained phobic stimulation. Viewing of spider pictures also resulted in increased activation of the amygdala in spider-phobic participants. This effect, however, was not fear specific because other affective materials evoked comparable signal strength in the amygdala. In contrast, insula activation was specifically increased during sustained phobic exposure in phobic volunteers. These data suggest that the activation of the amygdala in fMRI studies primarily indexes the detection of motivationally relevant stimuli whereas the insula might be more specifically linked to defensive response mobilization.
ARTICLE UPDATE - The role of medial temporal lobe in item recognition and source recollection of emotional stimuli.
Dougal S, Phelps EA, Davachi L.
Cognitive, Affective, Behavioural Neuroscience, 7, 233-242
Recent neuroimaging results suggest that distinct regions within the medial temporal lobe (MTL) may differentially support the episodic encoding of item and relational information for nonemotional stimuli . The present study was designed to assess whether these findings generalize to emotional stimuli. Behaviorally, we found that emotion reduced item recognition accuracy but did not reliably affect relational memory. fMRI analyses revealed that neutral and emotional words elicited distinct activation patterns within MTL regions predictive of subsequent memory. Consistent with previous findings for neutral words, hippocampal activation predicted later relational memory, whereas activation in the perirhinal cortex predicted successful item recognition. However, for emotional words, activation in the amygdala, hippocampus, and posterior parahippocampal cortex predicted item recognition only. These data suggest that MTL regions differentially support encoding of neutral and emotional stimuli.
Cognitive, Affective, Behavioural Neuroscience, 7, 233-242
Recent neuroimaging results suggest that distinct regions within the medial temporal lobe (MTL) may differentially support the episodic encoding of item and relational information for nonemotional stimuli . The present study was designed to assess whether these findings generalize to emotional stimuli. Behaviorally, we found that emotion reduced item recognition accuracy but did not reliably affect relational memory. fMRI analyses revealed that neutral and emotional words elicited distinct activation patterns within MTL regions predictive of subsequent memory. Consistent with previous findings for neutral words, hippocampal activation predicted later relational memory, whereas activation in the perirhinal cortex predicted successful item recognition. However, for emotional words, activation in the amygdala, hippocampus, and posterior parahippocampal cortex predicted item recognition only. These data suggest that MTL regions differentially support encoding of neutral and emotional stimuli.
ARTICLE UPDATE - Autonomic and prefrontal cortex responses to autobiographical recall of emotions.
Marci CD, Glick DM, Loh R, Dougherty DD.
Cognitive, Affective and Behavioural Neuroscience, 7, 243-250
The present study combined measures of regional cerebral blood flow (rCBF) using positron emission tomography (PET) with measures of the autonomic nervous system using skin conductance (SC), heart rate (HR), and the high frequency band of heart rate variability (HRV) in ten healthy participants who were exposed to autobiographical scripts of memories for three target emotions: anger, happiness, and sadness. According to the results, anger was the only emotion to show a significant increase in sympathetic activity, accompanied by a significant decrease in HRV when compared with a neutral script. Anger was also the only emotion to show significant changes in rCBF in the prefrontal cortex. By contrast, the results for the happy and sad conditions showed no significant increase in sympathetic activity and no changes in rCBF in the prefrontal cortex in comparison with the neutral script. The findings suggest that a relative increase in sympathetic activity with a reciprocal decrease in parasympathetic activity may be necessary to generate frontal activity in autobiographical recall of emotions.
Cognitive, Affective and Behavioural Neuroscience, 7, 243-250
The present study combined measures of regional cerebral blood flow (rCBF) using positron emission tomography (PET) with measures of the autonomic nervous system using skin conductance (SC), heart rate (HR), and the high frequency band of heart rate variability (HRV) in ten healthy participants who were exposed to autobiographical scripts of memories for three target emotions: anger, happiness, and sadness. According to the results, anger was the only emotion to show a significant increase in sympathetic activity, accompanied by a significant decrease in HRV when compared with a neutral script. Anger was also the only emotion to show significant changes in rCBF in the prefrontal cortex. By contrast, the results for the happy and sad conditions showed no significant increase in sympathetic activity and no changes in rCBF in the prefrontal cortex in comparison with the neutral script. The findings suggest that a relative increase in sympathetic activity with a reciprocal decrease in parasympathetic activity may be necessary to generate frontal activity in autobiographical recall of emotions.
ARTICLE UPDATE - Rapid detection of fear in body expressions, an ERP study.
van Heijnsbergen CC, Meeren HK, Grèzes J, de Gelder B.
Brain Research, in press
Recent findings indicate that the perceptual processing of fearful expressions in the face can already be initiated around 100–120 ms after stimulus presentation, demonstrating that emotional information of a face can be encoded before the identity of the face is fully recognized. At present it is not clear whether fear signals from body expressions may be encoded equally as rapid. To answer this question we investigated the early temporal dynamics of perceiving fearful body expression by measuring EEG. Participants viewed images of whole body actions presented either in a neutral or a fearful version. We observed an early emotion effect on the P1 peak latency around 112 ms post stimulus onset hitherto only found for facial expressions. Also consistent with the majority of facial expression studies, the N170 component elicited by perceiving bodies proved not to be sensitive for the expressed fear. In line with previous work, its vertex positive counterpart, the VPP, did show a condition-specific influence for fearful body expression. Our results indicate that the information provided by fearful body expression is already encoded in the early stages of visual processing, and suggest that similar early processing mechanisms are involved in the perception of fear in faces and bodies.
Brain Research, in press
Recent findings indicate that the perceptual processing of fearful expressions in the face can already be initiated around 100–120 ms after stimulus presentation, demonstrating that emotional information of a face can be encoded before the identity of the face is fully recognized. At present it is not clear whether fear signals from body expressions may be encoded equally as rapid. To answer this question we investigated the early temporal dynamics of perceiving fearful body expression by measuring EEG. Participants viewed images of whole body actions presented either in a neutral or a fearful version. We observed an early emotion effect on the P1 peak latency around 112 ms post stimulus onset hitherto only found for facial expressions. Also consistent with the majority of facial expression studies, the N170 component elicited by perceiving bodies proved not to be sensitive for the expressed fear. In line with previous work, its vertex positive counterpart, the VPP, did show a condition-specific influence for fearful body expression. Our results indicate that the information provided by fearful body expression is already encoded in the early stages of visual processing, and suggest that similar early processing mechanisms are involved in the perception of fear in faces and bodies.
ARTICLE UPDATE - Consciousness and arousal effects on emotional face processing as revealed by brain oscillations. A gamma band analysis.
Balconi M, Lucchiari C.
International Journal of Psychophysiology, in press
It remains an open question whether it is possible to assign a single brain operation or psychological function for facial emotion decoding to a certain type of oscillatory activity. Gamma band activity (GBA) offers an adequate tool for studying cortical activation patterns during emotional face information processing. In the present study brain oscillations were analyzed in response to facial expression of emotions. Specifically, GBA modulation was measured when twenty subjects looked at emotional (angry, fearful, happy, and sad faces) or neutral faces in two different conditions: supraliminal (10 ms) vs subliminal (150 ms) stimulation (100 target-mask pairs for each condition). The results showed that both consciousness and significance of the stimulus in terms of arousal can modulate the power synchronization (ERD decrease) during 150–350 time range: an early oscillatory event showed its peak at about 200 ms post-stimulus. GBA was enhanced by supraliminal more than subliminal elaboration, as well as more by high arousal (anger and fear) than low arousal (happiness and sadness) emotions. Finally a left-posterior dominance for conscious elaboration was found, whereas right hemisphere was discriminant in emotional processing of face in comparison with neutral face.
International Journal of Psychophysiology, in press
It remains an open question whether it is possible to assign a single brain operation or psychological function for facial emotion decoding to a certain type of oscillatory activity. Gamma band activity (GBA) offers an adequate tool for studying cortical activation patterns during emotional face information processing. In the present study brain oscillations were analyzed in response to facial expression of emotions. Specifically, GBA modulation was measured when twenty subjects looked at emotional (angry, fearful, happy, and sad faces) or neutral faces in two different conditions: supraliminal (10 ms) vs subliminal (150 ms) stimulation (100 target-mask pairs for each condition). The results showed that both consciousness and significance of the stimulus in terms of arousal can modulate the power synchronization (ERD decrease) during 150–350 time range: an early oscillatory event showed its peak at about 200 ms post-stimulus. GBA was enhanced by supraliminal more than subliminal elaboration, as well as more by high arousal (anger and fear) than low arousal (happiness and sadness) emotions. Finally a left-posterior dominance for conscious elaboration was found, whereas right hemisphere was discriminant in emotional processing of face in comparison with neutral face.
ARTICLE UPDATE - Feeling the Real World: Limbic Response to Music Depends on Related Content
Eran Eldar, Ori Ganor, Roee Admon, Avraham Bleich and Talma Hendler
Cerebral Cortex, 17, 2828-2840
Emotions are often object related—they are about someone or something in the world. It is yet an open question whether emotions and the associated perceptual contents that they refer to are processed by different parts of the brain or whether the brain regions that mediate emotions are also involved in the processing of the associated content they refer to. Using functional magnetic resonance imaging, we showed that simply combining music (rich in emotion but poor in information about the concrete world) with neutral films (poor in emotionality but rich in real-world details) yields increased activity in the amygdala, hippocampus, and lateral prefrontal regions. In contrast, emotional music on its own did not elicit a differential response in these regions. The finding that the amygdala, the heart of the emotional brain, responds increasingly to an emotional stimulus when it is associated with realistic scenes supports a fundamental role for concrete real-world content in emotional processing.
Cerebral Cortex, 17, 2828-2840
Emotions are often object related—they are about someone or something in the world. It is yet an open question whether emotions and the associated perceptual contents that they refer to are processed by different parts of the brain or whether the brain regions that mediate emotions are also involved in the processing of the associated content they refer to. Using functional magnetic resonance imaging, we showed that simply combining music (rich in emotion but poor in information about the concrete world) with neutral films (poor in emotionality but rich in real-world details) yields increased activity in the amygdala, hippocampus, and lateral prefrontal regions. In contrast, emotional music on its own did not elicit a differential response in these regions. The finding that the amygdala, the heart of the emotional brain, responds increasingly to an emotional stimulus when it is associated with realistic scenes supports a fundamental role for concrete real-world content in emotional processing.
ARTICLE UPDATE - As Time Goes By: Temporal Constraints on Emotional Activation of Inferior Medial Prefrontal Cortex
Jacob Geday, Ron Kupers and Albert Gjedde
Cerebral Cortex, 17, 2753-2759
To investigate the influence of stimulus duration on emotional processing, we measured changes of regional cerebral blood flow (rCBF) in 14 healthy subjects who viewed neutral or emotional images presented for 3 or 6 s. Presentation for 3 s reproduced the previous result of higher rCBF in inferior medial prefrontal cortex (IMPC) during neutral than emotional stimulation. Six-second presentation reverted this relationship, with activity in IMPC being higher during emotional stimulation. Prolonged stimulus presentation attenuated the rise of rCBF associated with emotions in left parietal cortex and cerebellar hemisphere. We speculate that the different rCBF during neutral and emotional stimulation for 6 s is a consequence of attention divided between the emotional stimuli and their associations. Thus, prefrontal activity rises when a cognitive task accompanies emotional stimulation because several cognitive processes compete for attention. The IMPC may serve the mechanism of attention underlying the concept of a default mode of brain function, selecting among competitive inputs from multiple brain regions rather than just processing emotions. The results emphasize the importance of implicit cognitive processing during emotional activation, however, unintended.
Cerebral Cortex, 17, 2753-2759
To investigate the influence of stimulus duration on emotional processing, we measured changes of regional cerebral blood flow (rCBF) in 14 healthy subjects who viewed neutral or emotional images presented for 3 or 6 s. Presentation for 3 s reproduced the previous result of higher rCBF in inferior medial prefrontal cortex (IMPC) during neutral than emotional stimulation. Six-second presentation reverted this relationship, with activity in IMPC being higher during emotional stimulation. Prolonged stimulus presentation attenuated the rise of rCBF associated with emotions in left parietal cortex and cerebellar hemisphere. We speculate that the different rCBF during neutral and emotional stimulation for 6 s is a consequence of attention divided between the emotional stimuli and their associations. Thus, prefrontal activity rises when a cognitive task accompanies emotional stimulation because several cognitive processes compete for attention. The IMPC may serve the mechanism of attention underlying the concept of a default mode of brain function, selecting among competitive inputs from multiple brain regions rather than just processing emotions. The results emphasize the importance of implicit cognitive processing during emotional activation, however, unintended.
Friday, November 09, 2007
ARTICLE UPDATE - Neuronal correlates of emotional processing in patients with major depression.
Frodl T, Scheuerecker J, Albrecht J, Kleemann AM, Müller-Schunk S, Koutsouleris N, Möller HJ, Brückmann H, Wiesmann M, Meisenzahl E.
World Journal of Biological Psychiatry, in press
Affective facial processing is an important component of interpersonal relationships, which is altered in patients with major depression. The study was designed to examine differences in functional brain activity between patients with major depression and healthy controls using functional magnetic resonance imaging (fMRI). Twelve patients with major depression and 12 age-, gender- and handedness-matched healthy controls were studied using fMRI. Subjects had to match facial emotional expressions in explicit trials, and gender of the presented faces in implicit trials. Patients showed higher blood oxygen level-dependent (BOLD) responses to implicit emotional stimuli than healthy controls in the left dorsolateral prefrontal cortex and the left precentral gyrus. Patients show a failure of deactivation in ACC, right dorsolateral prefrontal cortex (DLPFC) and right superior frontal cortex. Moreover, they exhibited smaller differences in BOLD responses in the left superior temporal lobe for the implicit contrasted to the explicit task, and in the cerebellum for the explicit contrasted to the implicit task compared to those of controls. Altered activation of the prefrontal cortex and anterior cingulum during emotion processing is a key feature of major depression.
World Journal of Biological Psychiatry, in press
Affective facial processing is an important component of interpersonal relationships, which is altered in patients with major depression. The study was designed to examine differences in functional brain activity between patients with major depression and healthy controls using functional magnetic resonance imaging (fMRI). Twelve patients with major depression and 12 age-, gender- and handedness-matched healthy controls were studied using fMRI. Subjects had to match facial emotional expressions in explicit trials, and gender of the presented faces in implicit trials. Patients showed higher blood oxygen level-dependent (BOLD) responses to implicit emotional stimuli than healthy controls in the left dorsolateral prefrontal cortex and the left precentral gyrus. Patients show a failure of deactivation in ACC, right dorsolateral prefrontal cortex (DLPFC) and right superior frontal cortex. Moreover, they exhibited smaller differences in BOLD responses in the left superior temporal lobe for the implicit contrasted to the explicit task, and in the cerebellum for the explicit contrasted to the implicit task compared to those of controls. Altered activation of the prefrontal cortex and anterior cingulum during emotion processing is a key feature of major depression.
ARTICLE UPDATE - Emotional attention: effects of emotion and gaze direction on overt orienting of visual attention.
Bonifacci P, Ricciardelli P, Lugli L, Pellicano A.
Cognitive Processing, in press
In the present study we considered the two factors that have been advocated for playing a role in emotional attention: perception of gaze direction and facial expression of emotions. Participants performed an oculomotor task in which they had to make a saccade towards one of the two lateral targets, depending on the colour of the fixation dot which appeared at the centre of the computer screen. At different time intervals (stimulus onset asynchronies, SOAs: 50,100,150 ms) following the onset of the dot, a picture of a human face (gazing either to the right or to the left) was presented at the centre of the screen. The gaze direction of the face could be congruent or incongruent with respect to the location of the target, and the expression could be neutral or angry. In Experiment 1 the facial expressions were presented randomly in a single block, whereas in Experiment 2 they were shown in separate blocks. Latencies for correct saccades and percentage of errors (saccade direction errors) were considered in the analyses. Results showed that incongruent trials determined a significantly higher percentage of saccade direction errors with respect to congruent trials, thus confirming that gaze direction, even when task-irrelevant, interferes with the accuracy of the observer's oculomotor behaviour. The angry expression was found to hold attention for a longer time with respect to the neutral one, producing delayed saccade latencies. This was particularly evident at 100 ms SOA and for incongruent trials. Emotional faces may then exert a modulatory effect on overt attention mechanisms.
Cognitive Processing, in press
In the present study we considered the two factors that have been advocated for playing a role in emotional attention: perception of gaze direction and facial expression of emotions. Participants performed an oculomotor task in which they had to make a saccade towards one of the two lateral targets, depending on the colour of the fixation dot which appeared at the centre of the computer screen. At different time intervals (stimulus onset asynchronies, SOAs: 50,100,150 ms) following the onset of the dot, a picture of a human face (gazing either to the right or to the left) was presented at the centre of the screen. The gaze direction of the face could be congruent or incongruent with respect to the location of the target, and the expression could be neutral or angry. In Experiment 1 the facial expressions were presented randomly in a single block, whereas in Experiment 2 they were shown in separate blocks. Latencies for correct saccades and percentage of errors (saccade direction errors) were considered in the analyses. Results showed that incongruent trials determined a significantly higher percentage of saccade direction errors with respect to congruent trials, thus confirming that gaze direction, even when task-irrelevant, interferes with the accuracy of the observer's oculomotor behaviour. The angry expression was found to hold attention for a longer time with respect to the neutral one, producing delayed saccade latencies. This was particularly evident at 100 ms SOA and for incongruent trials. Emotional faces may then exert a modulatory effect on overt attention mechanisms.
ARTICLE UPDATE - The Costs of Emotional Attention: Affective Processing Inhibits Subsequent Lexico-semantic Analysis
Niklas Ihssen, Sabine Heim and Andreas Keil
Journal of Cognitive Neuroscience, 19, 1932-1949
The human brain has evolved to process motivationally relevant information in an optimized manner. The perceptual benefit for emotionally arousing material, termed motivated attention, is indexed by electrocortical amplification at various levels of stimulus analysis. An outstanding issue, particularly on a neuronal level, refers to whether and how perceptual enhancement for arousing signals translates into modified processing of information presented in temporal or spatial proximity to the affective cue. The present studies aimed to examine facilitation and interference effects of task-irrelevant emotional pictures on subsequent word identification. In the context of forced-choice lexical decision tasks, pictures varying in hedonic valence and emotional arousal preceded word/pseudoword targets. Across measures and experiments, high-arousing compared to low-arousing pictures were associated with impaired processing of word targets. Arousing pleasant and unpleasant pictures prolonged word reaction times irrespective of stimulus-onset asynchrony (80 msec, 200 msec, 440 msec) and salient semantic category differences (e.g., erotica vs. mutilation pictures). On a neuronal level, interference was reflected in reduced N1 responses (204–264 msec) to both target types. Paralleling behavioral effects, suppression of the late positivity (404–704 msec) was more pronounced for word compared to pseudoword targets. Regional source modeling indicated that early reduction effects originated from inhibited cortical activity in posterior areas of the left inferior temporal cortex associated with orthographic processing. Modeling of later reduction effects argues for interference in distributed semantic networks comprising left anterior temporal and parietal sources. Thus, affective processing interferes with subsequent lexico-semantic analysis along the ventral stream.
Journal of Cognitive Neuroscience, 19, 1932-1949
The human brain has evolved to process motivationally relevant information in an optimized manner. The perceptual benefit for emotionally arousing material, termed motivated attention, is indexed by electrocortical amplification at various levels of stimulus analysis. An outstanding issue, particularly on a neuronal level, refers to whether and how perceptual enhancement for arousing signals translates into modified processing of information presented in temporal or spatial proximity to the affective cue. The present studies aimed to examine facilitation and interference effects of task-irrelevant emotional pictures on subsequent word identification. In the context of forced-choice lexical decision tasks, pictures varying in hedonic valence and emotional arousal preceded word/pseudoword targets. Across measures and experiments, high-arousing compared to low-arousing pictures were associated with impaired processing of word targets. Arousing pleasant and unpleasant pictures prolonged word reaction times irrespective of stimulus-onset asynchrony (80 msec, 200 msec, 440 msec) and salient semantic category differences (e.g., erotica vs. mutilation pictures). On a neuronal level, interference was reflected in reduced N1 responses (204–264 msec) to both target types. Paralleling behavioral effects, suppression of the late positivity (404–704 msec) was more pronounced for word compared to pseudoword targets. Regional source modeling indicated that early reduction effects originated from inhibited cortical activity in posterior areas of the left inferior temporal cortex associated with orthographic processing. Modeling of later reduction effects argues for interference in distributed semantic networks comprising left anterior temporal and parietal sources. Thus, affective processing interferes with subsequent lexico-semantic analysis along the ventral stream.
Friday, November 02, 2007
ARTICLE UPDATE - Neural correlates of adaptive decision making for risky gains and losses.
Weller JA, Levin IP, Shiv B, Bechara A.
Psychological Science, 18, 958-964
Do decisions about potential gains and potential losses require different neural structures for advantageous choices? In a lesion study, we used a new measure of adaptive decision making under risk to examine whether damage to neural structures subserving emotion affects an individual's ability to make adaptive decisions differentially for gains and losses. We found that individuals with lesions to the amygdala, an area responsible for processing emotional responses, displayed impaired decision making when considering potential gains, but not when considering potential losses. In contrast, patients with damage to the ventromedial prefrontal cortex, an area responsible for integrating cognitive and emotional information, showed deficits in both domains. We argue that this dissociation provides evidence that adaptive decision making for risks involving potential losses may be more difficult to disrupt than adaptive decision making for risks involving potential gains. This research further demonstrates the role of emotion in decision competence.
Psychological Science, 18, 958-964
Do decisions about potential gains and potential losses require different neural structures for advantageous choices? In a lesion study, we used a new measure of adaptive decision making under risk to examine whether damage to neural structures subserving emotion affects an individual's ability to make adaptive decisions differentially for gains and losses. We found that individuals with lesions to the amygdala, an area responsible for processing emotional responses, displayed impaired decision making when considering potential gains, but not when considering potential losses. In contrast, patients with damage to the ventromedial prefrontal cortex, an area responsible for integrating cognitive and emotional information, showed deficits in both domains. We argue that this dissociation provides evidence that adaptive decision making for risks involving potential losses may be more difficult to disrupt than adaptive decision making for risks involving potential gains. This research further demonstrates the role of emotion in decision competence.
ARTICLE UPDATE - Cerebral processing of emotional prosody-influence of acoustic parameters and arousal.
Wiethoff S, Wildgruber D, Kreifelts B, Becker H, Herbert C, Grodd W, Ethofer T.
Neuroimage, in press
The human brain has a preference for processing of emotionally salient stimuli. In the auditory modality, emotional prosody can induce such involuntary biasing of processing resources. To investigate the neural correlates underlying automatic processing of emotional information in the voice, words spoken in neutral, happy, erotic, angry, and fearful prosody were presented in a passive-listening functional magnetic resonance imaging (fMRI) experiment. Hemodynamic responses in right mid superior temporal gyrus (STG) were significantly stronger for all emotional than for neutral intonations. To disentangle the contribution of basic acoustic features and emotional arousal to this activation, the relation between event-related responses and these parameters was evaluated by means of regression analyses. A significant linear dependency between hemodynamic responses of right mid STG and mean intensity, mean fundamental frequency, variability of fundamental frequency, duration, and arousal of the stimuli was observed. While none of the acoustic parameters alone explained the stronger responses of right mid STG to emotional relative to neutral prosody, this stronger responsiveness was abolished both by correcting for arousal or the conjoint effect of the acoustic parameters. In conclusion, our results demonstrate that right mid STG is sensitive to various emotions conveyed by prosody, an effect which is driven by a combination of acoustic features that express the emotional arousal in the speaker’s voice.
Neuroimage, in press
The human brain has a preference for processing of emotionally salient stimuli. In the auditory modality, emotional prosody can induce such involuntary biasing of processing resources. To investigate the neural correlates underlying automatic processing of emotional information in the voice, words spoken in neutral, happy, erotic, angry, and fearful prosody were presented in a passive-listening functional magnetic resonance imaging (fMRI) experiment. Hemodynamic responses in right mid superior temporal gyrus (STG) were significantly stronger for all emotional than for neutral intonations. To disentangle the contribution of basic acoustic features and emotional arousal to this activation, the relation between event-related responses and these parameters was evaluated by means of regression analyses. A significant linear dependency between hemodynamic responses of right mid STG and mean intensity, mean fundamental frequency, variability of fundamental frequency, duration, and arousal of the stimuli was observed. While none of the acoustic parameters alone explained the stronger responses of right mid STG to emotional relative to neutral prosody, this stronger responsiveness was abolished both by correcting for arousal or the conjoint effect of the acoustic parameters. In conclusion, our results demonstrate that right mid STG is sensitive to various emotions conveyed by prosody, an effect which is driven by a combination of acoustic features that express the emotional arousal in the speaker’s voice.
ARTICLE UPDATE - Neural correlates of intrusion of emotion words in a modified Stroop task.
van Hooff JC, Dietz KC, Sharma D, Bowman H.
International Journal of Psychophysiology, in press
Behavioural studies have demonstrated that the emotional Stroop task is a valuable tool for investigating emotion–attention interactions in a variety of healthy and clinical populations, showing that participants are typically more distracted by negative stimuli as compared to neutral or positive stimuli. The main aim of this study was to find and examine the neural correlates of this greater intrusion from negative emotional stimuli. Reliable reaction time (RT) and event-related potential (ERP) data were collected from 23 participants who performed a manual emotional Stroop task with short (40 ms) and long (500 ms) inter-trial intervals. In the short interval condition, participants were found to produce longer RTs for negative than neutral words, suggesting that these stimuli were more difficult to ignore. This RT effect disappeared in the long interval condition, although larger P1 amplitudes were found for the negative words. This suggests that differences in early attention allocation may be unrelated to the degree of intrusion at the behavioural level. In addition, a larger negative slow wave around 300–700 ms post-stimulus was observed in the long interval condition, but only for those negative words that produced prolonged RTs as compared to their matched controls. This late and broadly distributed effect is believed to reflect suppression of meaning representations.
International Journal of Psychophysiology, in press
Behavioural studies have demonstrated that the emotional Stroop task is a valuable tool for investigating emotion–attention interactions in a variety of healthy and clinical populations, showing that participants are typically more distracted by negative stimuli as compared to neutral or positive stimuli. The main aim of this study was to find and examine the neural correlates of this greater intrusion from negative emotional stimuli. Reliable reaction time (RT) and event-related potential (ERP) data were collected from 23 participants who performed a manual emotional Stroop task with short (40 ms) and long (500 ms) inter-trial intervals. In the short interval condition, participants were found to produce longer RTs for negative than neutral words, suggesting that these stimuli were more difficult to ignore. This RT effect disappeared in the long interval condition, although larger P1 amplitudes were found for the negative words. This suggests that differences in early attention allocation may be unrelated to the degree of intrusion at the behavioural level. In addition, a larger negative slow wave around 300–700 ms post-stimulus was observed in the long interval condition, but only for those negative words that produced prolonged RTs as compared to their matched controls. This late and broadly distributed effect is believed to reflect suppression of meaning representations.
ARTICLE UPDATE - How emotion strengthens the recollective experience: a time-dependent hippocampal process.
Sharot T, Verfaellie M, Yonelinas AP.
PLoS ONE, 2, e1068
Emotion significantly strengthens the subjective recollective experience even when objective accuracy of the memory is not improved. Here, we examine if this modulation is related to the effect of emotion on hippocampal-dependent memory consolidation. Two critical predictions follow from this hypothesis. First, since consolidation is assumed to take time, the enhancement in the recollective experience for emotional compared to neutral memories should become more apparent following a delay. Second, if the emotion advantage is critically dependent on the hippocampus, then the effects should be reduced in amnesic patients with hippocampal damage. To test these predictions we examined the recollective experience for emotional and neutral photos at two retention intervals (Experiment 1), and in amnesics and controls (Experiment 2). Emotional memories were associated with an enhancement in the recollective experience that was greatest after a delay, whereas familiarity was not influenced by emotion. In amnesics with hippocampal damage the emotion effect on recollective experience was reduced. Surprisingly, however, these patients still showed a general memory advantage for emotional compared to neutral items, but this effect was manifest primarily as a facilitation of familiarity. The results support the consolidation hypothesis of recollective experience, but suggest that the effects of emotion on episodic memory are not exclusively hippocampally mediated. Rather, emotion may enhance recognition by facilitating familiarity when recollection is impaired due to hippocampal damage.
PLoS ONE, 2, e1068
Emotion significantly strengthens the subjective recollective experience even when objective accuracy of the memory is not improved. Here, we examine if this modulation is related to the effect of emotion on hippocampal-dependent memory consolidation. Two critical predictions follow from this hypothesis. First, since consolidation is assumed to take time, the enhancement in the recollective experience for emotional compared to neutral memories should become more apparent following a delay. Second, if the emotion advantage is critically dependent on the hippocampus, then the effects should be reduced in amnesic patients with hippocampal damage. To test these predictions we examined the recollective experience for emotional and neutral photos at two retention intervals (Experiment 1), and in amnesics and controls (Experiment 2). Emotional memories were associated with an enhancement in the recollective experience that was greatest after a delay, whereas familiarity was not influenced by emotion. In amnesics with hippocampal damage the emotion effect on recollective experience was reduced. Surprisingly, however, these patients still showed a general memory advantage for emotional compared to neutral items, but this effect was manifest primarily as a facilitation of familiarity. The results support the consolidation hypothesis of recollective experience, but suggest that the effects of emotion on episodic memory are not exclusively hippocampally mediated. Rather, emotion may enhance recognition by facilitating familiarity when recollection is impaired due to hippocampal damage.
Wednesday, October 31, 2007
ARTICLE UPDATE - Dissociating Motivational Direction and Affective Valence: Specific Emotions Alter Central Motor Processes
Coombes, Stephen A., Cauraugh, James H., Janelle, Christopher M
Psychological Science, 18, 938-942
We aimed to clarify the relation between affective valence and motivational direction by specifying how central and peripheral components of extension movements are altered according to specific unpleasant affective states. As predicted, premotor reaction time was quicker for extension movements initiated during exposure to attack than for extension movements initiated during exposure to all other valence categories (mutilation, erotic couples, opposite-sex nudes, neutral humans, household objects, blank). Exposure to erotic couples and mutilations yielded greater peak force than exposure to images of attack, neutral humans, and household objects. Finally, motor reaction time and peak electromyographic amplitude were not altered by valence. These findings indicate that unpleasant states do not unilaterally prime withdrawal movements, and that the quick execution of extension movements during exposure to threatening images is due to rapid premotor, rather than motor, reaction time. Collectively, our findings support the call for dissociating motivational direction and affective valence.
Psychological Science, 18, 938-942
We aimed to clarify the relation between affective valence and motivational direction by specifying how central and peripheral components of extension movements are altered according to specific unpleasant affective states. As predicted, premotor reaction time was quicker for extension movements initiated during exposure to attack than for extension movements initiated during exposure to all other valence categories (mutilation, erotic couples, opposite-sex nudes, neutral humans, household objects, blank). Exposure to erotic couples and mutilations yielded greater peak force than exposure to images of attack, neutral humans, and household objects. Finally, motor reaction time and peak electromyographic amplitude were not altered by valence. These findings indicate that unpleasant states do not unilaterally prime withdrawal movements, and that the quick execution of extension movements during exposure to threatening images is due to rapid premotor, rather than motor, reaction time. Collectively, our findings support the call for dissociating motivational direction and affective valence.
Friday, October 26, 2007
ARTICLE UPDATE - Time, space and emotion: fMRI reveals content-specific activation during text comprehension.
Ferstl EC, von Cramon DY.
Neuroscience Letters, in press
Story comprehension involves building a situation model of the text, i.e., a representation containing information on the who, where, when and why of the story. Using fMRI at 3T, domain-specific activations for three different information aspects were sought. Twenty participants read two sentence stories half of which contained inconsistencies concerning emotional, temporal or spatial information. Partly replicating previous results [E.C. Ferstl, M. Rinck, D.Y. von Cramon, Emotional and temporal aspects of situation model processing during text comprehension: an event-related fMRI study, J. Cogn. Neurosci. 17 (2005) 724–739], the anterior lateral prefrontal cortex/orbito-frontal cortex proved important for processing temporal information. The left anterior temporal lobe was particularly important during emotional stories. Most importantly, spatial information elicited bilateral activation in the collateral sulci and the posterior cingulate cortex, areas important for visuo-spatial cognition. These findings provide further evidence for content-specific processes during text comprehension.
Neuroscience Letters, in press
Story comprehension involves building a situation model of the text, i.e., a representation containing information on the who, where, when and why of the story. Using fMRI at 3T, domain-specific activations for three different information aspects were sought. Twenty participants read two sentence stories half of which contained inconsistencies concerning emotional, temporal or spatial information. Partly replicating previous results [E.C. Ferstl, M. Rinck, D.Y. von Cramon, Emotional and temporal aspects of situation model processing during text comprehension: an event-related fMRI study, J. Cogn. Neurosci. 17 (2005) 724–739], the anterior lateral prefrontal cortex/orbito-frontal cortex proved important for processing temporal information. The left anterior temporal lobe was particularly important during emotional stories. Most importantly, spatial information elicited bilateral activation in the collateral sulci and the posterior cingulate cortex, areas important for visuo-spatial cognition. These findings provide further evidence for content-specific processes during text comprehension.
ARTICLE UPDATE - Dissociated responses in the amygdala and orbitofrontal cortex to bottom-up and top-down components of emotional evaluation.
Wright P, Albarracin D, Brown RD, Li H, He G, Liu Y.
NeuroImage, in press
Although emotional responses to stimuli may be automatic, explicit evaluation of emotion is a voluntary act. These bottom-up and top-down processes may be supported by distinct neural systems. Previous studies reported bottom-up responses in the amygdala, top-down responses in the orbital and ventromedial prefrontal cortices, and top-down modulation of the amygdalar response. The current study used event-related fMRI on fifteen healthy males to examine these responses in the absence of stimulus anticipation or task repetition. Factorial analysis distinguished bottom-up responses in the amygdala from top-down responses in the orbitofrontal cortex. Activation of ventromedial prefrontal cortex and modulation of amygdalar response were not observed, and future studies may investigate whether these effects are contingent upon anticipation or cognitive set.
NeuroImage, in press
Although emotional responses to stimuli may be automatic, explicit evaluation of emotion is a voluntary act. These bottom-up and top-down processes may be supported by distinct neural systems. Previous studies reported bottom-up responses in the amygdala, top-down responses in the orbital and ventromedial prefrontal cortices, and top-down modulation of the amygdalar response. The current study used event-related fMRI on fifteen healthy males to examine these responses in the absence of stimulus anticipation or task repetition. Factorial analysis distinguished bottom-up responses in the amygdala from top-down responses in the orbitofrontal cortex. Activation of ventromedial prefrontal cortex and modulation of amygdalar response were not observed, and future studies may investigate whether these effects are contingent upon anticipation or cognitive set.
ARTICLE UPDATE - Typical Emotion Processing for Cartoon but not for Real Faces in Children with Autistic Spectrum Disorders.
Rosset DB, Rondan C, Da Fonseca D, Santos A, Assouline B, Deruelle C.
Journal of Autism and Developmental Disorders, in press
This study evaluated whether atypical face processing in autism extends from human to cartoon faces for which they show a greater interest. Twenty children with autistic spectrum disorders (ASD) were compared to two groups of typically developing children, matched on chronological and mental age. They processed the emotional expressions of real faces, human cartoon and non-human cartoon faces. Children with ASD were as capable as controls in processing emotional expressions, but strategies differed according to the type of face. Controls relied on a configural strategy with all faces. By contrast, ASD children exploited this typical configural strategy with cartoons but used a local strategy with real faces. This atypical visual processing style is discussed in the context of face expertise.
Journal of Autism and Developmental Disorders, in press
This study evaluated whether atypical face processing in autism extends from human to cartoon faces for which they show a greater interest. Twenty children with autistic spectrum disorders (ASD) were compared to two groups of typically developing children, matched on chronological and mental age. They processed the emotional expressions of real faces, human cartoon and non-human cartoon faces. Children with ASD were as capable as controls in processing emotional expressions, but strategies differed according to the type of face. Controls relied on a configural strategy with all faces. By contrast, ASD children exploited this typical configural strategy with cartoons but used a local strategy with real faces. This atypical visual processing style is discussed in the context of face expertise.
ARTICLE UPDATE - The human emotional brain without sleep - a prefrontal amygdala disconnect.
Yoo SS, Gujar N, Hu P, Jolesz FA, Walker MP.
Current Biology, 17, R877-878
Sleep deprivation is known to impair a range of functions, including immune regulation and metabolic control, as well as neurocognitive processes, such as learning and memory [1]. But evidence for the role of sleep in regulating our emotional brain-state is surprisingly scarce, and while the dysregulation of affective stability following sleep loss has received subjective documentation [2,3], any neural examination remains absent. Clinical evidence suggests that sleep and emotion interact; nearly all psychiatric and neurological disorders expressing sleep disruption display corresponding symptoms of affective imbalance [4]. Independent of sleep, knowledge of the basic neural and cognitive mechanisms regulating emotion is remarkably advanced. The amygdala has a well-documented role in the processing of emotionally salient information, particularly aversive stimuli [5,6]. The extent of amygdala engagement can also be influenced by a variety of connected systems, particularly the medial-prefrontal cortex (MPFC); the MPFC is proposed to exert an inhibitory, top-down control of amygdala function, resulting in contextually appropriate emotional responses [5,6]. We have focused on this network and using functional magnetic resonance image (fMRI) have obtained evidence, reported here, that a lack of sleep inappropriately modulates the human emotional brain response to negative aversive stimuli (see Supplemental data available on-line with this issue).
Current Biology, 17, R877-878
Sleep deprivation is known to impair a range of functions, including immune regulation and metabolic control, as well as neurocognitive processes, such as learning and memory [1]. But evidence for the role of sleep in regulating our emotional brain-state is surprisingly scarce, and while the dysregulation of affective stability following sleep loss has received subjective documentation [2,3], any neural examination remains absent. Clinical evidence suggests that sleep and emotion interact; nearly all psychiatric and neurological disorders expressing sleep disruption display corresponding symptoms of affective imbalance [4]. Independent of sleep, knowledge of the basic neural and cognitive mechanisms regulating emotion is remarkably advanced. The amygdala has a well-documented role in the processing of emotionally salient information, particularly aversive stimuli [5,6]. The extent of amygdala engagement can also be influenced by a variety of connected systems, particularly the medial-prefrontal cortex (MPFC); the MPFC is proposed to exert an inhibitory, top-down control of amygdala function, resulting in contextually appropriate emotional responses [5,6]. We have focused on this network and using functional magnetic resonance image (fMRI) have obtained evidence, reported here, that a lack of sleep inappropriately modulates the human emotional brain response to negative aversive stimuli (see Supplemental data available on-line with this issue).
Friday, October 19, 2007
ARTICLE UPDATE - Alteration of expected hemispheric asymmetries: Valence and arousal effects in neuropsychological models of emotion.
Alfano KM, Cimino CR.
Brain and Cognition, in press
The relative advantage of the left (LH) over the right hemisphere (RH) in processing of verbal material for most individuals is well established. Nevertheless, several studies have reported the ability of positively and negatively valenced stimuli to enhance and reverse, respectively, the usual LH>RH asymmetry. These studies, however, have used baseline stimuli that differed from emotional stimuli on two dimensions (i.e., valence and verbal/nonverbal nature), creating interpretive difficulties as to whether differences across these conditions are due to differences in valence or the verbal/nonverbal nature of the primes used in the baseline condition. In addition, these studies, along with many others in the literature, have failed to control for potential confounding effects of arousal. Emotional stimuli vary on dimensions of valence as well as arousal and arousal may be asymmetrically presented in the brain therefore contributing to observed asymmetries. Taken together, these considerations underscore the importance of controlling for both valence as well as arousal in any investigation of the effects of emotional stimuli. The objectives of the present study were twofold: (1) to employ an appropriate baseline condition to render emotional stimuli vs. baseline stimuli comparisons meaningful and (2) to examine the extent to which emotional verbal stimuli, equated for arousal level, alter the expected LH>RH asymmetry in a consonant trigram task. Results demonstrated that when LH lateralized consonant trigram presentations were preceded by a positive prime, an enhancement of the expected LH>RH asymmetry was observed. In contrast, when trigram presentations lateralized to the RH were preceded by a negative prime, a complete reversal of the typical asymmetry was found with RH>LH performance. These results are analogous to the pattern of relative hemispheric activations observed for various mood states. Controlling for arousal in studies investigating asymmetries associated with emotional processing may allow more clear interpretation of data intended to test predictions of neuropsychological models of emotion. Moreover, equating stimuli on the dimension of arousal as well as valence may shed more light on conflicting findings with regard to perception vs. expression of emotion.
Brain and Cognition, in press
The relative advantage of the left (LH) over the right hemisphere (RH) in processing of verbal material for most individuals is well established. Nevertheless, several studies have reported the ability of positively and negatively valenced stimuli to enhance and reverse, respectively, the usual LH>RH asymmetry. These studies, however, have used baseline stimuli that differed from emotional stimuli on two dimensions (i.e., valence and verbal/nonverbal nature), creating interpretive difficulties as to whether differences across these conditions are due to differences in valence or the verbal/nonverbal nature of the primes used in the baseline condition. In addition, these studies, along with many others in the literature, have failed to control for potential confounding effects of arousal. Emotional stimuli vary on dimensions of valence as well as arousal and arousal may be asymmetrically presented in the brain therefore contributing to observed asymmetries. Taken together, these considerations underscore the importance of controlling for both valence as well as arousal in any investigation of the effects of emotional stimuli. The objectives of the present study were twofold: (1) to employ an appropriate baseline condition to render emotional stimuli vs. baseline stimuli comparisons meaningful and (2) to examine the extent to which emotional verbal stimuli, equated for arousal level, alter the expected LH>RH asymmetry in a consonant trigram task. Results demonstrated that when LH lateralized consonant trigram presentations were preceded by a positive prime, an enhancement of the expected LH>RH asymmetry was observed. In contrast, when trigram presentations lateralized to the RH were preceded by a negative prime, a complete reversal of the typical asymmetry was found with RH>LH performance. These results are analogous to the pattern of relative hemispheric activations observed for various mood states. Controlling for arousal in studies investigating asymmetries associated with emotional processing may allow more clear interpretation of data intended to test predictions of neuropsychological models of emotion. Moreover, equating stimuli on the dimension of arousal as well as valence may shed more light on conflicting findings with regard to perception vs. expression of emotion.
ARTICLE UPDATE - Neural correlates of emotion regulation in psychopathology.
Taylor SF, Liberzon I.
Trends in Cognitive Sciences, in press
What can psychopathology and its treatment tell us about cognitive emotional interactions? Standard approaches to interactions between emotion and cognition often adopt a variant of the idea that cognitive processes, subserved by dorsal and lateral cortical circuits, exert control and regulation of ventral, limbic brain areas associated with emotional expression and experience. However, it is becoming clear from studies on depression, post-traumatic stress disorder (PTSD) and obsessive compulsive disorder (OCD), that a binary, opponent theory of cognitive emotion interaction (CEI) and the dorsal-ventral model of neurocircuitry do not fully describe the data. We summarize recent research to suggest that networks of direct and indirect pathways exist by which cognition can regulate pathological emotion, and the inter-relationships of specific nodes within the networks need to be characterized.
Trends in Cognitive Sciences, in press
What can psychopathology and its treatment tell us about cognitive emotional interactions? Standard approaches to interactions between emotion and cognition often adopt a variant of the idea that cognitive processes, subserved by dorsal and lateral cortical circuits, exert control and regulation of ventral, limbic brain areas associated with emotional expression and experience. However, it is becoming clear from studies on depression, post-traumatic stress disorder (PTSD) and obsessive compulsive disorder (OCD), that a binary, opponent theory of cognitive emotion interaction (CEI) and the dorsal-ventral model of neurocircuitry do not fully describe the data. We summarize recent research to suggest that networks of direct and indirect pathways exist by which cognition can regulate pathological emotion, and the inter-relationships of specific nodes within the networks need to be characterized.
ARTICLE UPDATE - Better Late Than Never? On the Dynamics of Online Regulation of Sadness Using Distraction and Cognitive Reappraisal.
Sheppes G, Meiran N.
Personality and Social Psychology Bulletin, in press
Real-life emotion regulation often occurs at some point after an emotion-triggering event (ETE) has been introduced, but most previous research has involved regulation before or after the ETE. In a series of experiments, the authors examined online regulation via distraction and cognitive reappraisal by manipulating the strategy initiation point in sadness-evoking films. Distraction was effective even when initiated late, presumably because it involves diluting the ETE contents by mixing them with a nonsad input. By contrast, reappraisal was less effective when initiated late, suggesting a possible point of no return for this strategy: Adopting a detached view late in the ETE may be difficult because it involves continued focus on the ETE, and hence requires overcoming a previously formed tendency of identifying with the emotional content.
Personality and Social Psychology Bulletin, in press
Real-life emotion regulation often occurs at some point after an emotion-triggering event (ETE) has been introduced, but most previous research has involved regulation before or after the ETE. In a series of experiments, the authors examined online regulation via distraction and cognitive reappraisal by manipulating the strategy initiation point in sadness-evoking films. Distraction was effective even when initiated late, presumably because it involves diluting the ETE contents by mixing them with a nonsad input. By contrast, reappraisal was less effective when initiated late, suggesting a possible point of no return for this strategy: Adopting a detached view late in the ETE may be difficult because it involves continued focus on the ETE, and hence requires overcoming a previously formed tendency of identifying with the emotional content.
ARTICLE UPDATE - Multiple Cues in Social Perception: The Time Course of Processing Race and Facial Expression.
Kubota JT, Ito TA.
Journal of Experimental Social Psychology, 43, 738-752
The purpose of the present study was to examine the time course of race and expression processing to determine how these cues influence early perceptual as well as explicit categorization judgments. Despite their importance in social perception, little research has examined how social category information and emotional expression are processed over time. Moreover, although models of face processing suggest that the two cues should be processed independently, this has rarely been directly examined. Event-related brain potentials were recorded as participants made race and emotion categorization judgments of Black and White men posing either happy, angry, or neutral expressions. Our findings support that processing of race and emotion cues occur independently and in parallel, relatively early in processing.
Journal of Experimental Social Psychology, 43, 738-752
The purpose of the present study was to examine the time course of race and expression processing to determine how these cues influence early perceptual as well as explicit categorization judgments. Despite their importance in social perception, little research has examined how social category information and emotional expression are processed over time. Moreover, although models of face processing suggest that the two cues should be processed independently, this has rarely been directly examined. Event-related brain potentials were recorded as participants made race and emotion categorization judgments of Black and White men posing either happy, angry, or neutral expressions. Our findings support that processing of race and emotion cues occur independently and in parallel, relatively early in processing.
Wednesday, October 17, 2007
ARTICLE UDPATE - How Negative Emotion Enhances the Visual Specificity of a Memory
Elizabeth A. Kensinger, Rachel J. Garoff-Eaton and Daniel L. Schacter
Journal of Cognitive Neuroscience, 19, 1872-1887
Some studies have suggested that emotion primarily increases memory for "gist," and does not enhance memory for detail. There are, however, some instances in which negative objects (e.g., snake, grenade) are remembered with more visual detail than neutral objects (e.g., barometer, blender). In the present functional magnetic resonance imaging (fMRI) study, we examined the encoding processes that lead a person to remember the exact visual details of negative and neutral objects, and to remember which of two decisions were made about the objects (a size decision or an animacy decision). The enhancement in memory for a negative item's visual details appeared to result from enhanced visual processing: The right fusiform gyrus, a region known to be critical for processing exemplar-specific details, showed a greater extent and magnitude of activity during the successful encoding of negative objects. Activity in the right amygdala also corresponded with memory for visual detail, although it did not relate to memory for the task performed with the item. These data provide strong evidence that engagement of some amygdalar regions can correspond with enhanced memory for certain types of details, but does not ensure successful encoding of all contextual details.
Journal of Cognitive Neuroscience, 19, 1872-1887
Some studies have suggested that emotion primarily increases memory for "gist," and does not enhance memory for detail. There are, however, some instances in which negative objects (e.g., snake, grenade) are remembered with more visual detail than neutral objects (e.g., barometer, blender). In the present functional magnetic resonance imaging (fMRI) study, we examined the encoding processes that lead a person to remember the exact visual details of negative and neutral objects, and to remember which of two decisions were made about the objects (a size decision or an animacy decision). The enhancement in memory for a negative item's visual details appeared to result from enhanced visual processing: The right fusiform gyrus, a region known to be critical for processing exemplar-specific details, showed a greater extent and magnitude of activity during the successful encoding of negative objects. Activity in the right amygdala also corresponded with memory for visual detail, although it did not relate to memory for the task performed with the item. These data provide strong evidence that engagement of some amygdalar regions can correspond with enhanced memory for certain types of details, but does not ensure successful encoding of all contextual details.
Tuesday, October 16, 2007
ARTICLE UPDATE - The role of medial temporal lobe in item recognition and source recollection of emotional stimuli
Dougal, Sonya; Phelps, Elizabeth A.; Davachi, Lila
Cognitive, Affective, & Behavioral Neuroscience, 7, 233-242
Recent neuroimaging results suggest that distinct regions within the medial temporal lobe (MTL) may differentially support the episodic encoding of item and relational information for nonemotional stimuli (for a review, see Davachi, 2006). The present study was designed to assess whether these findings generalize to emotional stimuli. Behaviorally, we found that emotion reduced item recognition accuracy but did not reliably affect relational memory. fMRI analyses revealed that neutral and emotional words elicited distinct activation patterns within MTL regions predictive of subsequent memory. Consistent with previous findings for neutral words, hippocampal activation predicted later relational memory, whereas activation in the perirhinal cortex predicted successful item recognition. However, for emotional words, activation in the amygdala, hippocampus, and posterior parahippocampal cortex predicted item recognition only. These data suggest that MTL regions differentially support encoding of neutral and emotional stimuli.
Cognitive, Affective, & Behavioral Neuroscience, 7, 233-242
Recent neuroimaging results suggest that distinct regions within the medial temporal lobe (MTL) may differentially support the episodic encoding of item and relational information for nonemotional stimuli (for a review, see Davachi, 2006). The present study was designed to assess whether these findings generalize to emotional stimuli. Behaviorally, we found that emotion reduced item recognition accuracy but did not reliably affect relational memory. fMRI analyses revealed that neutral and emotional words elicited distinct activation patterns within MTL regions predictive of subsequent memory. Consistent with previous findings for neutral words, hippocampal activation predicted later relational memory, whereas activation in the perirhinal cortex predicted successful item recognition. However, for emotional words, activation in the amygdala, hippocampus, and posterior parahippocampal cortex predicted item recognition only. These data suggest that MTL regions differentially support encoding of neutral and emotional stimuli.
ARTICLE UPDATE - Autonomic and prefrontal cortex responses to autobiographical recall of emotions
Marci, Carl D.; Glick, Debra M.; Loh, Rebecca; Dougherty, Darin D.
Cognitive, Affective, & Behavioral Neuroscience, 7, 243-250
The present study combined measures of regional cerebral blood flow (rCBF) using positron emission tomography (PET) with measures of the autonomic nervous system using skin conductance (SC), heart rate (HR), and the high frequency band of heart rate variability (HRV) in ten healthy participants who were exposed to autobiographical scripts of memories for three target emotions: anger, happiness, and sadness. According to the results, anger was the only emotion to show a significant increase in sympathetic activity, accompanied by a significant decrease in HRV when compared with a neutral script. Anger was also the only emotion to show significant changes in rCBF in the prefrontal cortex. By contrast, the results for the happy and sad conditions showed no significant increase in sympathetic activity and no changes in rCBF in the prefrontal cortex in comparison with the neutral script. The findings suggest that a relative increase in sympathetic activity with a reciprocal decrease in parasympathetic activity may be necessary to generate frontal activity in autobiographical recall of emotions.
Cognitive, Affective, & Behavioral Neuroscience, 7, 243-250
The present study combined measures of regional cerebral blood flow (rCBF) using positron emission tomography (PET) with measures of the autonomic nervous system using skin conductance (SC), heart rate (HR), and the high frequency band of heart rate variability (HRV) in ten healthy participants who were exposed to autobiographical scripts of memories for three target emotions: anger, happiness, and sadness. According to the results, anger was the only emotion to show a significant increase in sympathetic activity, accompanied by a significant decrease in HRV when compared with a neutral script. Anger was also the only emotion to show significant changes in rCBF in the prefrontal cortex. By contrast, the results for the happy and sad conditions showed no significant increase in sympathetic activity and no changes in rCBF in the prefrontal cortex in comparison with the neutral script. The findings suggest that a relative increase in sympathetic activity with a reciprocal decrease in parasympathetic activity may be necessary to generate frontal activity in autobiographical recall of emotions.
Friday, October 12, 2007
ARTICLE UPDATE - Neural and Behavioral Evidence for Affective Priming from Unconsciously Perceived Emotional Facial Expressions and the Influence of T
Li W, Zinbarg RE, Boehm SG, Paller KA.
Journal of Cognitive Neuroscience, in press
Abstract Affective judgments can often be influenced by emotional information people unconsciously perceive, but the neural mechanisms responsible for these effects and how they are modulated by individual differences in sensitivity to threat are unclear. Here we studied subliminal affective priming by recording brain potentials to surprise faces preceded by 30-msec happy or fearful prime faces. Participants showed valence-consistent changes in affective ratings of surprise faces, although they reported no knowledge of prime-face expressions, nor could they discriminate between prime-face expressions in a forced-choice test. In conjunction with the priming effect on affective evaluation, larger occipital P1 potentials at 145-175 msec were found with fearful than with happy primes, and source analyses implicated the bilateral extrastriate cortex in this effect. Later brain potentials at 300-400 msec were enhanced with happy versus fearful primes, which may reflect differential attentional orienting. Personality testing for sensitivity to threat, especially social threat, was also used to evaluate individual differences potentially relevant to subliminal affective priming. Indeed, participants with high trait anxiety demonstrated stronger affective priming and greater P1 differences than did those with low trait anxiety, and these effects were driven by fearful primes. Results thus suggest that unconsciously perceived affective information influences social judgments by altering very early perceptual analyses, and that this influence is accentuated to the extent that people are oversensitive to threat. In this way, perception may be subject to a variety of influences that govern social preferences in the absence of concomitant awareness of such influences.
Journal of Cognitive Neuroscience, in press
Abstract Affective judgments can often be influenced by emotional information people unconsciously perceive, but the neural mechanisms responsible for these effects and how they are modulated by individual differences in sensitivity to threat are unclear. Here we studied subliminal affective priming by recording brain potentials to surprise faces preceded by 30-msec happy or fearful prime faces. Participants showed valence-consistent changes in affective ratings of surprise faces, although they reported no knowledge of prime-face expressions, nor could they discriminate between prime-face expressions in a forced-choice test. In conjunction with the priming effect on affective evaluation, larger occipital P1 potentials at 145-175 msec were found with fearful than with happy primes, and source analyses implicated the bilateral extrastriate cortex in this effect. Later brain potentials at 300-400 msec were enhanced with happy versus fearful primes, which may reflect differential attentional orienting. Personality testing for sensitivity to threat, especially social threat, was also used to evaluate individual differences potentially relevant to subliminal affective priming. Indeed, participants with high trait anxiety demonstrated stronger affective priming and greater P1 differences than did those with low trait anxiety, and these effects were driven by fearful primes. Results thus suggest that unconsciously perceived affective information influences social judgments by altering very early perceptual analyses, and that this influence is accentuated to the extent that people are oversensitive to threat. In this way, perception may be subject to a variety of influences that govern social preferences in the absence of concomitant awareness of such influences.
ARTICLE UPDATE - Neural correlates of emotional working memory in patients with mild cognitive impairment.
Döhnel K, Sommer M, Ibach B, Rothmayr C, Meinhardt J, Hajak G.
Neuropsychologia, in press
Emotional stimuli can have beneficial effects on memory in healthy aged subjects and partly on patients with dementia. So far, no experimental study has explored the effects of memory for emotional stimuli in patients with mild cognitive impairment (MCI), a concept that describes a transitional state between normal aging and dementia. The present fMRI study explored working memory for emotional stimuli in 16 patients with amnestic MCI (aMCI) and 16 healthy aged participants. Subjects performed an n-back task (2-back) with neutral, positive, and negative emotional pictures. The analysis focused on target processing. Results showed that groups did not differ in working memory performance. In healthy aged participants emotional targets had no significant impact on working memory. In patients with aMCI a negativity bias was observed, indicating that negative targets were better remembered compared to neutral and positive targets. Regarding fMRI results, both groups showed an increase in functional activity in prefrontal and lateral parietal brain regions associated with target processing. As a key result, we observed significant group by emotion interaction effects in the precuneus. Healthy aged participants showed a signal decrease in the left precuneus for positive compared to neutral targets. The precuneus deactivation in healthy aged participants may indicate a disengagement of self-referential processes towards task-related processes. Patients with aMCI revealed a signal increase in the right precuneus for negative compared to neutral targets. This increase in precuneus activity, combined with a behavioural facilitation effect, may indicate a mechanism to compensate disease related processes in aMCI.
Neuropsychologia, in press
Emotional stimuli can have beneficial effects on memory in healthy aged subjects and partly on patients with dementia. So far, no experimental study has explored the effects of memory for emotional stimuli in patients with mild cognitive impairment (MCI), a concept that describes a transitional state between normal aging and dementia. The present fMRI study explored working memory for emotional stimuli in 16 patients with amnestic MCI (aMCI) and 16 healthy aged participants. Subjects performed an n-back task (2-back) with neutral, positive, and negative emotional pictures. The analysis focused on target processing. Results showed that groups did not differ in working memory performance. In healthy aged participants emotional targets had no significant impact on working memory. In patients with aMCI a negativity bias was observed, indicating that negative targets were better remembered compared to neutral and positive targets. Regarding fMRI results, both groups showed an increase in functional activity in prefrontal and lateral parietal brain regions associated with target processing. As a key result, we observed significant group by emotion interaction effects in the precuneus. Healthy aged participants showed a signal decrease in the left precuneus for positive compared to neutral targets. The precuneus deactivation in healthy aged participants may indicate a disengagement of self-referential processes towards task-related processes. Patients with aMCI revealed a signal increase in the right precuneus for negative compared to neutral targets. This increase in precuneus activity, combined with a behavioural facilitation effect, may indicate a mechanism to compensate disease related processes in aMCI.
ARTICLE UPDATE - Influence of attention manipulation on emotion and autonomic responses.
Murakami H, Ohira H.
Perceptual Motor Skills, 105, 299-308
Psychopathologies such as depression and anxiety have been associated with self-consciousness, a trait focusing on the self in terms of emotions and social images. A technique designed to shift attention away from the self tends to reduce anxiety, so the present purpose was to assess the effect of self body-state information on an individual's emotional and autonomic activity. 24 undergraduate and graduate students (10 men and 14 women), ages 19 to 27 years (M = 22.1, SD = 2.5), were recruited as subjects. Focusing on body-state during an anxiety-inducing situation led to an increase of low to high frequency ratio of heart-rate variability which reflected cardiac sympathovagal balance. That is, attending to one's own bodily states enhanced relative sympathetic activity compared to parasympathetic activity, which can be interpreted as one of the physiological emotional responses elicited by anxiety.
Perceptual Motor Skills, 105, 299-308
Psychopathologies such as depression and anxiety have been associated with self-consciousness, a trait focusing on the self in terms of emotions and social images. A technique designed to shift attention away from the self tends to reduce anxiety, so the present purpose was to assess the effect of self body-state information on an individual's emotional and autonomic activity. 24 undergraduate and graduate students (10 men and 14 women), ages 19 to 27 years (M = 22.1, SD = 2.5), were recruited as subjects. Focusing on body-state during an anxiety-inducing situation led to an increase of low to high frequency ratio of heart-rate variability which reflected cardiac sympathovagal balance. That is, attending to one's own bodily states enhanced relative sympathetic activity compared to parasympathetic activity, which can be interpreted as one of the physiological emotional responses elicited by anxiety.
ARTICLE UPDATE - Top-down predictions in the cognitive brain.
Kveraga K, Ghuman AS, Bar M.
Brain and Cognition, in press (not available online yet for unknown reason)
The human brain is not a passive organ simply waiting to be activated by external stimuli. Instead, we propose that the brain continuously employs memory of past experiences to interpret sensory information and predict the immediately relevant future. The basic elements of this proposal include analogical mapping, associative representations and the generation of predictions. This review concentrates on visual recognition as the model system for developing and testing ideas about the role and mechanisms of top-down predictions in the brain. We cover relevant behavioral, computational and neural aspects, explore links to emotion and action preparation, and consider clinical implications for schizophrenia and dyslexia. We then discuss the extension of the general principles of this proposal to other cognitive domains.
Brain and Cognition, in press (not available online yet for unknown reason)
The human brain is not a passive organ simply waiting to be activated by external stimuli. Instead, we propose that the brain continuously employs memory of past experiences to interpret sensory information and predict the immediately relevant future. The basic elements of this proposal include analogical mapping, associative representations and the generation of predictions. This review concentrates on visual recognition as the model system for developing and testing ideas about the role and mechanisms of top-down predictions in the brain. We cover relevant behavioral, computational and neural aspects, explore links to emotion and action preparation, and consider clinical implications for schizophrenia and dyslexia. We then discuss the extension of the general principles of this proposal to other cognitive domains.
Monday, October 08, 2007
ARTICLE UPDATE - Unilateral Amygdala Lesions Hamper Attentional Orienting Triggered by Gaze Direction
Tomoko Akiyama, Motoichiro Kato, Taro Muramatsu, Satoshi Umeda, Fumie Saito and Haruo Kashima
Cerebral Cortex, in press
The newly discovered deficit in a bilateral amygdala-damaged case, of not being able to allocate attention to the critical feature of a face (Adolphs R, Gosselin F, Buchanan TW, Tranel D, Schyns P, Damasio AR. 2005. A mechanism for impaired fear recognition after amygdala damage. Nature. 433:68--72.), has opened a new window into the function of the amygdala. This case implies that the amygdala might be essential in detecting potentially relevant social stimuli, and directing attention accordingly. In this study, we have sought to test this implication by investigating the behavioral performance of 5 unilateral amygdala-damaged subjects on spatial cueing tasks. The tasks employed central gaze and arrow direction as cues to trigger attentional orienting in peripheral target detection. Although age-matched normal controls demonstrated a significant congruency effect such that targets presented congruently to cue direction elicited faster detection, amygdala subjects demonstrated no such congruency effect for gaze cues in the face of a significant congruency effect for arrow cues. The results suggest that the social valence of a stimulus is critical for amygdala involvement in visual processing. The results also support the implicated role of the amygdala in detecting and analyzing relevant social stimuli, and orienting attention accordingly.
Cerebral Cortex, in press
The newly discovered deficit in a bilateral amygdala-damaged case, of not being able to allocate attention to the critical feature of a face (Adolphs R, Gosselin F, Buchanan TW, Tranel D, Schyns P, Damasio AR. 2005. A mechanism for impaired fear recognition after amygdala damage. Nature. 433:68--72.), has opened a new window into the function of the amygdala. This case implies that the amygdala might be essential in detecting potentially relevant social stimuli, and directing attention accordingly. In this study, we have sought to test this implication by investigating the behavioral performance of 5 unilateral amygdala-damaged subjects on spatial cueing tasks. The tasks employed central gaze and arrow direction as cues to trigger attentional orienting in peripheral target detection. Although age-matched normal controls demonstrated a significant congruency effect such that targets presented congruently to cue direction elicited faster detection, amygdala subjects demonstrated no such congruency effect for gaze cues in the face of a significant congruency effect for arrow cues. The results suggest that the social valence of a stimulus is critical for amygdala involvement in visual processing. The results also support the implicated role of the amygdala in detecting and analyzing relevant social stimuli, and orienting attention accordingly.
Friday, October 05, 2007
ARTICLE UPDATE - Rapid picture processing: Affective primes and targets.
Flaisch T, Junghöfer M, Bradley MM, Schupp HT, Lang PJ.
Psychophysiology, in press
In rapid serial visual presentation of pictures, an early ERP component shows enlarged negativity over occipital regions for emotional, compared to neutral, pictures. The present study examined the processing of emotional target pictures as a function of the hedonic valence of a preceding prime picture. Dense sensor ERPs were measured while subjects viewed a continuous stream of pleasant, neutral, and unpleasant pictures, presented for 335 ms each. Two main findings were observed: First, replicating previous results, emotional target pictures were associated with a larger posterior negativity, compared to neutral pictures. Second, the emotional content of the preceding prime picture affected target processing, with pleasant or unpleasant primes resulting in reduced negativity of the following picture, irrespective of its emotional valence. These findings are discussed within a framework of competition among successive pictures.
Psychophysiology, in press
In rapid serial visual presentation of pictures, an early ERP component shows enlarged negativity over occipital regions for emotional, compared to neutral, pictures. The present study examined the processing of emotional target pictures as a function of the hedonic valence of a preceding prime picture. Dense sensor ERPs were measured while subjects viewed a continuous stream of pleasant, neutral, and unpleasant pictures, presented for 335 ms each. Two main findings were observed: First, replicating previous results, emotional target pictures were associated with a larger posterior negativity, compared to neutral pictures. Second, the emotional content of the preceding prime picture affected target processing, with pleasant or unpleasant primes resulting in reduced negativity of the following picture, irrespective of its emotional valence. These findings are discussed within a framework of competition among successive pictures.
ARTICLE UPDATE - The coupling of emotion and cognition in the eye: Introducing the pupil old/new effect.
Võ ML, Jacobs AM, Kuchinke L, Hofmann M, Conrad M, Schacht A, Hutzler F.
Psychophysiology, in press
The study presented here investigated the effects of emotional valence on the memory for words by assessing both memory performance and pupillary responses during a recognition memory task. Participants had to make speeded judgments on whether a word presented in the test phase of the experiment had already been presented ("old") or not ("new"). An emotion-induced recognition bias was observed: Words with emotional content not only produced a higher amount of hits, but also elicited more false alarms than neutral words. Further, we found a distinct pupil old/new effect characterized as an elevated pupillary response to hits as opposed to correct rejections. Interestingly, this pupil old/new effect was clearly diminished for emotional words. We therefore argue that the pupil old/new effect is not only able to mirror memory retrieval processes, but also reflects modulation by an emotion-induced recognition bias.
Psychophysiology, in press
The study presented here investigated the effects of emotional valence on the memory for words by assessing both memory performance and pupillary responses during a recognition memory task. Participants had to make speeded judgments on whether a word presented in the test phase of the experiment had already been presented ("old") or not ("new"). An emotion-induced recognition bias was observed: Words with emotional content not only produced a higher amount of hits, but also elicited more false alarms than neutral words. Further, we found a distinct pupil old/new effect characterized as an elevated pupillary response to hits as opposed to correct rejections. Interestingly, this pupil old/new effect was clearly diminished for emotional words. We therefore argue that the pupil old/new effect is not only able to mirror memory retrieval processes, but also reflects modulation by an emotion-induced recognition bias.
Friday, September 28, 2007
ARTICLE UPDATE - The Neural Bases of Emotion Regulation: Reappraisal and Suppression of Negative Emotion.
Goldin PR, McRae K, Ramel W, Gross JJ.
Biological Psychiatry, in press
Background
Emotion regulation strategies are thought to differ in when and how they influence the emotion-generative process. However, no study to date has directly probed the neural bases of two contrasting (e.g., cognitive versus behavioral) emotion regulation strategies. This study used functional magnetic resonance imaging (fMRI) to examine cognitive reappraisal (a cognitive strategy thought to have its impact early in the emotion-generative process) and expressive suppression (a behavioral strategy thought to have its impact later in the emotion-generative process).
Methods
Seventeen women viewed 15 sec neutral and negative emotion-eliciting films under four conditions—watch-neutral, watch-negative, reappraise-negative, and suppress-negative—while providing emotion experience ratings and having their facial expressions videotaped.
Results
Reappraisal resulted in early (0–4.5 sec) prefrontal cortex (PFC) responses, decreased negative emotion experience, and decreased amygdala and insular responses. Suppression produced late (10.5–15 sec) PFC responses, decreased negative emotion behavior and experience, but increased amygdala and insular responses.
Conclusions
These findings demonstrate the differential efficacy of reappraisal and suppression on emotional experience, facial behavior, and neural response and highlight intriguing differences in the temporal dynamics of these two emotion regulation strategies.
Key Words: Amygdala; cognitive control; emotion; emotion regulation; fMRI; insula
Biological Psychiatry, in press
Background
Emotion regulation strategies are thought to differ in when and how they influence the emotion-generative process. However, no study to date has directly probed the neural bases of two contrasting (e.g., cognitive versus behavioral) emotion regulation strategies. This study used functional magnetic resonance imaging (fMRI) to examine cognitive reappraisal (a cognitive strategy thought to have its impact early in the emotion-generative process) and expressive suppression (a behavioral strategy thought to have its impact later in the emotion-generative process).
Methods
Seventeen women viewed 15 sec neutral and negative emotion-eliciting films under four conditions—watch-neutral, watch-negative, reappraise-negative, and suppress-negative—while providing emotion experience ratings and having their facial expressions videotaped.
Results
Reappraisal resulted in early (0–4.5 sec) prefrontal cortex (PFC) responses, decreased negative emotion experience, and decreased amygdala and insular responses. Suppression produced late (10.5–15 sec) PFC responses, decreased negative emotion behavior and experience, but increased amygdala and insular responses.
Conclusions
These findings demonstrate the differential efficacy of reappraisal and suppression on emotional experience, facial behavior, and neural response and highlight intriguing differences in the temporal dynamics of these two emotion regulation strategies.
Key Words: Amygdala; cognitive control; emotion; emotion regulation; fMRI; insula
ARTICLE UPDATE - Self produced and observed actions influence emotion: the roles of action fluency and eye gaze.
Hayes AE, Paul MA, Beuger B, Tipper SP.
Psychological Research, in press
Affective responses to objects can be influenced by cognitive processes such as perceptual fluency. Here we investigated whether the quality of motor interaction with an object influences affective response to the object. Participants grasped and moved objects using either a fluent action or a non-fluent action (avoiding an obstacle). Liking ratings were higher for objects in the fluent condition. Two further studies investigated whether the fluency of another person's actions influences affective response. Observers watched movie clips of the motor actions described above, in conditions where the observed actor could be seen to be looking towards the grasped object, or where the actor's head and gaze were not visible. Two results were observed: First, when the actor's gaze cannot be seen, liking ratings of the objects are reduced. Second, action fluency of observed actions does influence liking ratings, but only when the actor's gaze towards the object is visible. These findings provide supporting evidence for the important role of observed eye gaze in action simulation, and demonstrate that non-emotive actions can evoke empathic states in observers.
Psychological Research, in press
Affective responses to objects can be influenced by cognitive processes such as perceptual fluency. Here we investigated whether the quality of motor interaction with an object influences affective response to the object. Participants grasped and moved objects using either a fluent action or a non-fluent action (avoiding an obstacle). Liking ratings were higher for objects in the fluent condition. Two further studies investigated whether the fluency of another person's actions influences affective response. Observers watched movie clips of the motor actions described above, in conditions where the observed actor could be seen to be looking towards the grasped object, or where the actor's head and gaze were not visible. Two results were observed: First, when the actor's gaze cannot be seen, liking ratings of the objects are reduced. Second, action fluency of observed actions does influence liking ratings, but only when the actor's gaze towards the object is visible. These findings provide supporting evidence for the important role of observed eye gaze in action simulation, and demonstrate that non-emotive actions can evoke empathic states in observers.
Friday, September 21, 2007
ARTICLE UPDATE - Things are sounding up: affective influences on auditory tone perception.
Weger UW, Meier BP, Robinson MD, Inhoff AW.
Psychonomic Bulletin & Review, 14, 517-521
Recent studies have documented robust and intriguing associations between affect and performance in cognitive tasks. The present two experiments sought to extend this line of work with reference to potential cross-modal effects. Specifically, the present studies examined whether word evaluations would bias subsequent judgments of low- and high-pitch tones. Because affective metaphors and related associations consistently indicate that positive is high and negative is low, we predicted and found that positive evaluations biased tone judgment in the direction of high-pitch tones, whereas the opposite was true of negative evaluations. Effects were found on accuracy rates, response biases, and reaction times. These effects occurred despite the irrelevance of prime evaluations to the tone judgment task. In addition to clarifying the nature of these cross-modal associations, the present results further the idea that affective evaluations exert large effects on perceptual judgments related to verticality.
Psychonomic Bulletin & Review, 14, 517-521
Recent studies have documented robust and intriguing associations between affect and performance in cognitive tasks. The present two experiments sought to extend this line of work with reference to potential cross-modal effects. Specifically, the present studies examined whether word evaluations would bias subsequent judgments of low- and high-pitch tones. Because affective metaphors and related associations consistently indicate that positive is high and negative is low, we predicted and found that positive evaluations biased tone judgment in the direction of high-pitch tones, whereas the opposite was true of negative evaluations. Effects were found on accuracy rates, response biases, and reaction times. These effects occurred despite the irrelevance of prime evaluations to the tone judgment task. In addition to clarifying the nature of these cross-modal associations, the present results further the idea that affective evaluations exert large effects on perceptual judgments related to verticality.
ARTICLE UPDATE - Social anxiety and interpretation biases for facial displays of emotion: Emotion detection and ratings of social cost.
Schofield CA, Coles ME, Gibb BE.
Behavioral Research and Therapy, in press
The current study assessed the processing of facial displays of emotion (Happy, Disgust, and Neutral) of varying emotional intensities in participants with high vs. low social anxiety. Use of facial expressions of varying intensities allowed for strong external validity and a fine-grained analysis of interpretation biases. Sensitivity to perceiving negative evaluation in faces (i.e., emotion detection) was assessed at both long (unlimited) and brief (60ms) stimulus durations. In addition, ratings of perceived social cost were made indicating what participants judged it would be like to have a social interaction with a person exhibiting the stimulus emotion. Results suggest that high social anxiety participants did not demonstrate biases in their sensitivity to perceiving negative evaluation (i.e. disgust) in facial expressions. However, high social anxiety participants did estimate the perceived cost of interacting with someone showing disgust to be significantly greater than low social anxiety participants, regardless of the intensity of the disgust expression. These results are consistent with a specific type of interpretation bias in which participants with social anxiety have elevated ratings of the social cost of interacting with individuals displaying negative evaluation.
Behavioral Research and Therapy, in press
The current study assessed the processing of facial displays of emotion (Happy, Disgust, and Neutral) of varying emotional intensities in participants with high vs. low social anxiety. Use of facial expressions of varying intensities allowed for strong external validity and a fine-grained analysis of interpretation biases. Sensitivity to perceiving negative evaluation in faces (i.e., emotion detection) was assessed at both long (unlimited) and brief (60ms) stimulus durations. In addition, ratings of perceived social cost were made indicating what participants judged it would be like to have a social interaction with a person exhibiting the stimulus emotion. Results suggest that high social anxiety participants did not demonstrate biases in their sensitivity to perceiving negative evaluation (i.e. disgust) in facial expressions. However, high social anxiety participants did estimate the perceived cost of interacting with someone showing disgust to be significantly greater than low social anxiety participants, regardless of the intensity of the disgust expression. These results are consistent with a specific type of interpretation bias in which participants with social anxiety have elevated ratings of the social cost of interacting with individuals displaying negative evaluation.
ARTICLE UPDATE - Dynamics of Visual Information Integration in the Brain for Categorizing Facial Expressions.
Schyns PG, Petro LS, Smith ML.
Current Biology, 17, 1580-1585
A key to understanding visual cognition is to determine when, how, and with what information the human brain distinguishes between visual categories. So far, the dynamics of information processing for categorization of visual stimuli has not been elucidated. By using an ecologically important categorization task (seven expressions of emotion), we demonstrate, in three human observers, that an early brain event (the N170 Event Related Potential, occurring 170 ms after stimulus onset [1-16]) integrates visual information specific to each expression, according to a pattern. Specifically, starting 50 ms prior to the ERP peak, facial information tends to be integrated from the eyes downward in the face. This integration stops, and the ERP peaks, when the information diagnostic for judging a particular expression has been integrated (e.g., the eyes in fear, the corners of the nose in disgust, or the mouth in happiness). Consequently, the duration of information integration from the eyes down determines the latency of the N170 for each expression (e.g., with "fear" being faster than "disgust," itself faster than "happy"). For the first time in visual categorization, we relate the dynamics of an important brain event to the dynamics of a precise information-processing function.
Current Biology, 17, 1580-1585
A key to understanding visual cognition is to determine when, how, and with what information the human brain distinguishes between visual categories. So far, the dynamics of information processing for categorization of visual stimuli has not been elucidated. By using an ecologically important categorization task (seven expressions of emotion), we demonstrate, in three human observers, that an early brain event (the N170 Event Related Potential, occurring 170 ms after stimulus onset [1-16]) integrates visual information specific to each expression, according to a pattern. Specifically, starting 50 ms prior to the ERP peak, facial information tends to be integrated from the eyes downward in the face. This integration stops, and the ERP peaks, when the information diagnostic for judging a particular expression has been integrated (e.g., the eyes in fear, the corners of the nose in disgust, or the mouth in happiness). Consequently, the duration of information integration from the eyes down determines the latency of the N170 for each expression (e.g., with "fear" being faster than "disgust," itself faster than "happy"). For the first time in visual categorization, we relate the dynamics of an important brain event to the dynamics of a precise information-processing function.
ARTICLE UPDATE - Own-sex effects in emotional memory for faces.
Armony JL, Sergerie K.
Neuroscience Letters, in press
The amygdala is known to be critical for the enhancement of memory for emotional, especially negative, material. Importantly, some researchers have suggested a sex-specific hemispheric lateralization in this process. In the case of facial expressions, another important factor that could influence memory success is the sex of the face, which could interact with the emotion depicted as well as with the sex of the perceiver. Whether this is the case remains unknown, as all previous studies of sex difference in emotional memory have employed affective pictures. Here we directly explored this question using functional magnetic resonance imaging in a subsequent memory paradigm for facial expressions (fearful, happy and neutral). Consistent with our hypothesis, we found that the hemispheric laterality of the amygdala involvement in successful memory for emotional material was influenced not only by the sex of the subjects, as previously proposed, but also by the sex of the faces being remembered. Namely, the left amygdala was more active for successfully remembered female fearful faces in women, whereas in men the right amygdala was more involved in memory for male fearful faces. These results confirm the existence of sex differences in amygdala lateralization in emotional memory but also demonstrate a subtle relationship between the observer and the stimulus in this process.
Neuroscience Letters, in press
The amygdala is known to be critical for the enhancement of memory for emotional, especially negative, material. Importantly, some researchers have suggested a sex-specific hemispheric lateralization in this process. In the case of facial expressions, another important factor that could influence memory success is the sex of the face, which could interact with the emotion depicted as well as with the sex of the perceiver. Whether this is the case remains unknown, as all previous studies of sex difference in emotional memory have employed affective pictures. Here we directly explored this question using functional magnetic resonance imaging in a subsequent memory paradigm for facial expressions (fearful, happy and neutral). Consistent with our hypothesis, we found that the hemispheric laterality of the amygdala involvement in successful memory for emotional material was influenced not only by the sex of the subjects, as previously proposed, but also by the sex of the faces being remembered. Namely, the left amygdala was more active for successfully remembered female fearful faces in women, whereas in men the right amygdala was more involved in memory for male fearful faces. These results confirm the existence of sex differences in amygdala lateralization in emotional memory but also demonstrate a subtle relationship between the observer and the stimulus in this process.
ARTICLE UPDATE - "Remembering" emotional words is based on response bias, not recollection.
Dougal S, Rotello CM.
Psychonomic Bulletin & Review, 14, 423-429
Recent studies have demonstrated that emotional stimuli result in a higher proportion of recognized items that are "remembered" (e.g., Kensinger & Corkin, 2003; Ochsner, 2000), leading to greater estimates of recollection by the dual-process model (Yonelinas, 1994). This result suggests that recognition judgments to emotional stimuli depend on a recollection process. We challenge this conclusion with receiver operating characteristic (ROC) curve data from two experiments. In both experiments, subjects studied neutral and emotional words. During the recognition test, subjects made old-new confidence ratings as well as remember-know judgments. Four models of remember-know judgments were fit to individual subjects' data: two versions of a one-dimensional signal-detection-based model (Donaldson, 1996; Wixted & Stretch, 2004), the dual-process model (Yonelinas, 1994), and the two-dimensional signal-detection-based model known as STREAK (Rotello, Macmillan, & Reeder, 2004). Consistent with the literature, we found that emotion increases subjective reports of "remembering:" However, our ROC analyses and modeling work reveal that the effect is due to response bias differences rather than sensitivity change or use of a high-threshold recollection process.
Psychonomic Bulletin & Review, 14, 423-429
Recent studies have demonstrated that emotional stimuli result in a higher proportion of recognized items that are "remembered" (e.g., Kensinger & Corkin, 2003; Ochsner, 2000), leading to greater estimates of recollection by the dual-process model (Yonelinas, 1994). This result suggests that recognition judgments to emotional stimuli depend on a recollection process. We challenge this conclusion with receiver operating characteristic (ROC) curve data from two experiments. In both experiments, subjects studied neutral and emotional words. During the recognition test, subjects made old-new confidence ratings as well as remember-know judgments. Four models of remember-know judgments were fit to individual subjects' data: two versions of a one-dimensional signal-detection-based model (Donaldson, 1996; Wixted & Stretch, 2004), the dual-process model (Yonelinas, 1994), and the two-dimensional signal-detection-based model known as STREAK (Rotello, Macmillan, & Reeder, 2004). Consistent with the literature, we found that emotion increases subjective reports of "remembering:" However, our ROC analyses and modeling work reveal that the effect is due to response bias differences rather than sensitivity change or use of a high-threshold recollection process.
Monday, September 17, 2007
ARTICLE UPDATE - Taking the Feeling out of Emotional Memories - A Study of Hypnotic Emotional Numbing: A Brief Communication
Bryant RA, Fearns S.
International Journal of Clinical and Experimental Hypnosis, 55, 426-434
This study investigated the influence of hypnotic emotional inhibition on emotional response to and recall of emotional features of autobiographical memories. Twenty-nine high hypnotizable participants were administered a hypnotic induction and either emotional suppression or control instructions and then were asked to recall a personal distressing or neutral autobiographical memory. Dependent variables included self-reported emotion, EMG corrugator muscle activity, and use of affective descriptors in autobiographical memories. Participants in the suppression condition displayed less emotional responsivity on self-report and EMG corrugator muscle activity than other participants during recall of the distressing memory. In contrast, emotional suppression did not influence the use of affective descriptors in the content of personal memories. These findings point to the capacity for hypnotic emotional inhibition to differentially influence affective and semantic components of the emotional response.SE
International Journal of Clinical and Experimental Hypnosis, 55, 426-434
This study investigated the influence of hypnotic emotional inhibition on emotional response to and recall of emotional features of autobiographical memories. Twenty-nine high hypnotizable participants were administered a hypnotic induction and either emotional suppression or control instructions and then were asked to recall a personal distressing or neutral autobiographical memory. Dependent variables included self-reported emotion, EMG corrugator muscle activity, and use of affective descriptors in autobiographical memories. Participants in the suppression condition displayed less emotional responsivity on self-report and EMG corrugator muscle activity than other participants during recall of the distressing memory. In contrast, emotional suppression did not influence the use of affective descriptors in the content of personal memories. These findings point to the capacity for hypnotic emotional inhibition to differentially influence affective and semantic components of the emotional response.SE
ARTICLE UPDATE - Is a neutral face really evaluated as being emotionally neutral?
Lee E, Kang JI, Park IH, Kim JJ, An SK.
Psychiatry Research, in press
Most of the functional neuroimaging studies on emotion have used neutral faces as a baseline condition. The aim of the present study was to explore whether prototypical neutral faces are evaluated as displaying neutral emotions. Twenty-one subjects performed the Extrinsic Affective Simon Task (EAST), a validated implicit task that measures the emotional evaluation of target stimuli. All stimuli consisted of two juxtaposed faces from standardized facial pictures. The attribute stimuli (positive vs. negative), which needed to be classified on the basis of extrinsic valence, were presented as black and white facial pictures. The target stimuli were color-filtered positive, negative, neutral, and positive/negative faces, and subjects were instructed to classify them on the basis of the filtered color (blue vs. green). The responses to the positive target faces were associated with the positive emotions and the responses to the negative target faces were associated with the negative emotions. For the neutral faces, the responses were similar to those of negative faces, while for the positive/negative stimuli, the responses were undifferentiated. These findings suggested that prototypical “neutral” faces may be evaluated as negative in some circumstances, which suggests that the inclusion of neutral faces as a baseline condition might introduce an experimental confound in functional neuroimaging studies.
Psychiatry Research, in press
Most of the functional neuroimaging studies on emotion have used neutral faces as a baseline condition. The aim of the present study was to explore whether prototypical neutral faces are evaluated as displaying neutral emotions. Twenty-one subjects performed the Extrinsic Affective Simon Task (EAST), a validated implicit task that measures the emotional evaluation of target stimuli. All stimuli consisted of two juxtaposed faces from standardized facial pictures. The attribute stimuli (positive vs. negative), which needed to be classified on the basis of extrinsic valence, were presented as black and white facial pictures. The target stimuli were color-filtered positive, negative, neutral, and positive/negative faces, and subjects were instructed to classify them on the basis of the filtered color (blue vs. green). The responses to the positive target faces were associated with the positive emotions and the responses to the negative target faces were associated with the negative emotions. For the neutral faces, the responses were similar to those of negative faces, while for the positive/negative stimuli, the responses were undifferentiated. These findings suggested that prototypical “neutral” faces may be evaluated as negative in some circumstances, which suggests that the inclusion of neutral faces as a baseline condition might introduce an experimental confound in functional neuroimaging studies.
Friday, September 07, 2007
ARTICLE UPDATE - Opposing influences of emotional and non-emotional distracters upon sustained prefrontal cortex activity during a delayed-response wo
Dolcos F, Diaz-Granados P, Wang L, McCarthy G.
Neuropsychologia, in press
Performance in delayed-response working memory (WM) tasks is typically associated with sustained activation in the dorsolateral prefrontal cortex (dlPFC) that spans the delay between the memoranda and the memory probe. Recent studies have demonstrated that novel distracters presented during the delay interval both affect sustained activation and impair WM performance. However, the effect of the performance-impairing distracters upon sustained dlPFC delay activity was related to the characteristics of the distracters: memoranda-confusable distracters increased delay activity, whereas memoranda-nonconfusable emotional distracters decreased delay activity. Because these different effects were observed in different studies, it is possible that different dlPFC regions were involved and the paradox is more apparent than real. To investigate this possibility, event-related fMRI data were recorded while subjects performed a WM task for faces with memoranda-confusable (novel faces) and memoranda-nonconfusable emotional (novel scenes) distracters presented during the delay interval. Consistent with previous findings, confusable face distracters increased dlPFC delay activity, while nonconfusable emotional distracters decreased dlPFC delay activity, and these opposing effects modulated activity in the same dlPFC regions. These results provide direct evidence that specific regions of the dlPFC are generally involved in mediating the effects of distraction, while showing sensitivity to the nature of distraction. These findings are relevant for understanding alterations in the neural mechanisms associated with both general impairment of cognitive control and with specific impairment in the ability to control emotional distraction, such as those observed in aging and affective disorders, respectively.
Neuropsychologia, in press
Performance in delayed-response working memory (WM) tasks is typically associated with sustained activation in the dorsolateral prefrontal cortex (dlPFC) that spans the delay between the memoranda and the memory probe. Recent studies have demonstrated that novel distracters presented during the delay interval both affect sustained activation and impair WM performance. However, the effect of the performance-impairing distracters upon sustained dlPFC delay activity was related to the characteristics of the distracters: memoranda-confusable distracters increased delay activity, whereas memoranda-nonconfusable emotional distracters decreased delay activity. Because these different effects were observed in different studies, it is possible that different dlPFC regions were involved and the paradox is more apparent than real. To investigate this possibility, event-related fMRI data were recorded while subjects performed a WM task for faces with memoranda-confusable (novel faces) and memoranda-nonconfusable emotional (novel scenes) distracters presented during the delay interval. Consistent with previous findings, confusable face distracters increased dlPFC delay activity, while nonconfusable emotional distracters decreased dlPFC delay activity, and these opposing effects modulated activity in the same dlPFC regions. These results provide direct evidence that specific regions of the dlPFC are generally involved in mediating the effects of distraction, while showing sensitivity to the nature of distraction. These findings are relevant for understanding alterations in the neural mechanisms associated with both general impairment of cognitive control and with specific impairment in the ability to control emotional distraction, such as those observed in aging and affective disorders, respectively.
ARTICLE UPDATE - Anxiety and orienting of gaze to angry and fearful faces.
Mogg K, Garner M, Bradley BP.
Biological Psychology, in press
Neuroscience research indicates that individual differences in anxiety may be attributable to a neural system for threat-processing, involving the amygdala, which modulates attentional vigilance, and which is more sensitive to fearful than angry faces. Complementary cognitive studies indicate that high-anxious individuals show enhanced visuospatial orienting towards angry faces, but it is unclear whether fearful faces elicit a similar attentional bias. This study compared biases in initial orienting of gaze to fearful and angry faces, which varied in emotional intensity, in high- and low-anxious individuals. Gaze was monitored whilst participants viewed a series of face-pairs. Results showed that fearful and angry faces elicited similar attentional biases. High-anxious individuals were more likely to direct gaze at intense negative facial expressions, than low-anxious individuals, whereas the groups did not differ in orienting to mild negative expressions. Implications of the findings for research into the neural and cognitive bases of emotion processing are discussed.
Biological Psychology, in press
Neuroscience research indicates that individual differences in anxiety may be attributable to a neural system for threat-processing, involving the amygdala, which modulates attentional vigilance, and which is more sensitive to fearful than angry faces. Complementary cognitive studies indicate that high-anxious individuals show enhanced visuospatial orienting towards angry faces, but it is unclear whether fearful faces elicit a similar attentional bias. This study compared biases in initial orienting of gaze to fearful and angry faces, which varied in emotional intensity, in high- and low-anxious individuals. Gaze was monitored whilst participants viewed a series of face-pairs. Results showed that fearful and angry faces elicited similar attentional biases. High-anxious individuals were more likely to direct gaze at intense negative facial expressions, than low-anxious individuals, whereas the groups did not differ in orienting to mild negative expressions. Implications of the findings for research into the neural and cognitive bases of emotion processing are discussed.
ARTICLE UPDATE - Congruency, attentional set, and laterality effects with emotional words.
Techentin C, Voyer D.
Neuropsychology, 21, 646-655
The present study investigated the influence of attention and word-emotion congruency on auditory asymmetries with stimuli that include verbal and emotional components. Words were presented dichotically to 80 participants and were pronounced in either congruent or incongruent emotional tones. Participants were asked to identify the presence of a target word or emotion under 1 of 2 conditions. The blocked condition required detection of a word or emotional target in separate blocks. In the randomized condition, the target was changed across trials by means of a postcue. A right-ear advantage (REA) and a left-ear advantage (LEA) were found for word and emotion targets, respectively. However, the finding of a Condition x Stimulus Type x Ear x Congruency interaction indicated that in the randomized condition, a REA was obtained for words when the stimuli were congruent and a LEA was observed for emotions when the stimuli were incongruent. The findings suggest that randomizing the target reduced the influence of the attentional set established by blocking the target. It is likely that this promoted the detection of hemispheric interference in the randomized condition.
Neuropsychology, 21, 646-655
The present study investigated the influence of attention and word-emotion congruency on auditory asymmetries with stimuli that include verbal and emotional components. Words were presented dichotically to 80 participants and were pronounced in either congruent or incongruent emotional tones. Participants were asked to identify the presence of a target word or emotion under 1 of 2 conditions. The blocked condition required detection of a word or emotional target in separate blocks. In the randomized condition, the target was changed across trials by means of a postcue. A right-ear advantage (REA) and a left-ear advantage (LEA) were found for word and emotion targets, respectively. However, the finding of a Condition x Stimulus Type x Ear x Congruency interaction indicated that in the randomized condition, a REA was obtained for words when the stimuli were congruent and a LEA was observed for emotions when the stimuli were incongruent. The findings suggest that randomizing the target reduced the influence of the attentional set established by blocking the target. It is likely that this promoted the detection of hemispheric interference in the randomized condition.
ARTICLE UPDATE - Neural Biases to Covert and Overt Signals of Fear: Dissociation by Trait Anxiety and Depression
Leanne M. Williams, Andrew H. Kemp, Kim Felmingham, Belinda J. Liddell, Donna M. Palmer and Richard A. Bryant
Journal of Cognitive Neuroscience, 19, 1595-1608
Although biases toward signals of fear may be an evolutionary adaptation necessary for survival, heightened biases may be maladaptive and associated with anxiety or depression. In this study, event-related potentials (ERPs) were used to examine the time course of neural responses to facial fear stimuli (versus neutral) presented overtly (for 500 msec with conscious attention) and covertly (for 10 msec with immediate masking to preclude conscious awareness) in 257 nonclinical subjects. We also examined the impact of trait anxiety and depression, assessed using psychometric ratings, on the time course of ERPs. In the total subject group, controlled biases to overtly processed fear were reflected in an enhancement of ERPs associated with structural encoding (120–220 msec) and sustained evaluation persisting from 250 msec and beyond, following a temporo-occipital to frontal topography. By contrast, covert fear processing elicited automatic biases, reflected in an enhancement of ERPs prior to structural encoding (80–180 msec) and again in the period associated with automatic orienting and emotion encoding (230–330 msec), which followed the reverse frontal to temporo-occipital topography. Higher levels of trait anxiety (in the clinical range) were distinguished by a heightened bias to covert fear (speeding of early ERPs), compared to higher depression which was associated with an opposing bias to overt fear (slowing of later ERPs). Anxiety also heightened early responses to covert fear, and depression to overt fear, with subsequent deficits in emotion encoding in each case. These findings are consistent with neural biases to signals of fear which operate automatically and during controlled processing, feasibly supported by parallel networks. Heightened automatic biases in anxiety may contribute to a cycle of hypervigilance and anxious thoughts, whereas depression may represent a "burnt out" emotional state in which evaluation of fear stimuli is prolonged only when conscious attention is allocated.
Journal of Cognitive Neuroscience, 19, 1595-1608
Although biases toward signals of fear may be an evolutionary adaptation necessary for survival, heightened biases may be maladaptive and associated with anxiety or depression. In this study, event-related potentials (ERPs) were used to examine the time course of neural responses to facial fear stimuli (versus neutral) presented overtly (for 500 msec with conscious attention) and covertly (for 10 msec with immediate masking to preclude conscious awareness) in 257 nonclinical subjects. We also examined the impact of trait anxiety and depression, assessed using psychometric ratings, on the time course of ERPs. In the total subject group, controlled biases to overtly processed fear were reflected in an enhancement of ERPs associated with structural encoding (120–220 msec) and sustained evaluation persisting from 250 msec and beyond, following a temporo-occipital to frontal topography. By contrast, covert fear processing elicited automatic biases, reflected in an enhancement of ERPs prior to structural encoding (80–180 msec) and again in the period associated with automatic orienting and emotion encoding (230–330 msec), which followed the reverse frontal to temporo-occipital topography. Higher levels of trait anxiety (in the clinical range) were distinguished by a heightened bias to covert fear (speeding of early ERPs), compared to higher depression which was associated with an opposing bias to overt fear (slowing of later ERPs). Anxiety also heightened early responses to covert fear, and depression to overt fear, with subsequent deficits in emotion encoding in each case. These findings are consistent with neural biases to signals of fear which operate automatically and during controlled processing, feasibly supported by parallel networks. Heightened automatic biases in anxiety may contribute to a cycle of hypervigilance and anxious thoughts, whereas depression may represent a "burnt out" emotional state in which evaluation of fear stimuli is prolonged only when conscious attention is allocated.
Friday, August 31, 2007
ARTICLE UPDATE - Amygdala activation in affective priming: a magnetoencephalogram study.
Garolera M, Coppola R, Muñoz KE, Elvevåg B, Carver FW, Weinberger DR, Goldberg TE.
NeurReport, 18, 1449-1453
We employed magnetoencephalography (MEG) to examine amygdala activity during a linguistic affective priming task. The experimental design included positive and negative word pairs. Using synthetic aperture magnetometry in the analysis of MEG data, we identified a left amygdala power increase in the theta frequency range during priming involving negative words. We found that the amygdala displayed a time-dependent intensification in responsiveness to negative stimuli, specifically between 150 and 400 ms after target presentation. This study provides evidence for theta power changes in the amygdala and demonstrates that the analysis of brain oscillations provides a powerful tool to explore mechanisms implicated in emotional processing.
NeurReport, 18, 1449-1453
We employed magnetoencephalography (MEG) to examine amygdala activity during a linguistic affective priming task. The experimental design included positive and negative word pairs. Using synthetic aperture magnetometry in the analysis of MEG data, we identified a left amygdala power increase in the theta frequency range during priming involving negative words. We found that the amygdala displayed a time-dependent intensification in responsiveness to negative stimuli, specifically between 150 and 400 ms after target presentation. This study provides evidence for theta power changes in the amygdala and demonstrates that the analysis of brain oscillations provides a powerful tool to explore mechanisms implicated in emotional processing.
ARTICLE UPDATE - Retrieval of emotional memories.
Buchanan TW.
Psychological Bulletin, 133, 761-779
Long-term memories are influenced by the emotion experienced during learning as well as by the emotion experienced during memory retrieval. The present article reviews the literature addressing the effects of emotion on retrieval, focusing on the cognitive and neurological mechanisms that have been revealed. The reviewed research suggests that the amygdala, in combination with the hippocampus and prefrontal cortex, plays an important role in the retrieval of memories for emotional events. The neural regions necessary for online emotional processing also influence emotional memory retrieval, perhaps through the reexperience of emotion during the retrieval process.
Psychological Bulletin, 133, 761-779
Long-term memories are influenced by the emotion experienced during learning as well as by the emotion experienced during memory retrieval. The present article reviews the literature addressing the effects of emotion on retrieval, focusing on the cognitive and neurological mechanisms that have been revealed. The reviewed research suggests that the amygdala, in combination with the hippocampus and prefrontal cortex, plays an important role in the retrieval of memories for emotional events. The neural regions necessary for online emotional processing also influence emotional memory retrieval, perhaps through the reexperience of emotion during the retrieval process.
ARTICLE UPDATE - Social learning of fear
Andreas Olsson & Elizabeth A Phelps
Nature Neuroscience, 10, 1095-1102
Research across species highlights the critical role of the amygdala in fear conditioning. However, fear conditioning, involving direct aversive experience, is only one means by which fears can be acquired. Exploiting aversive experiences of other individuals through social fear learning is less risky. Behavioral research provides important insights into the workings of social fear learning, and the neural mechanisms are beginning to be understood. We review research suggesting that an amygdala-centered model of fear conditioning can help to explain social learning of fear through observation and instruction. We also describe how observational and instructed fear is distinguished by involvement of additional neural systems implicated in social-emotional behavior, language and explicit memory, and propose a modified conditioning model to account for social fear learning. A better understanding of social fear learning promotes integration of biological principles of learning with cultural evolution.
Nature Neuroscience, 10, 1095-1102
Research across species highlights the critical role of the amygdala in fear conditioning. However, fear conditioning, involving direct aversive experience, is only one means by which fears can be acquired. Exploiting aversive experiences of other individuals through social fear learning is less risky. Behavioral research provides important insights into the workings of social fear learning, and the neural mechanisms are beginning to be understood. We review research suggesting that an amygdala-centered model of fear conditioning can help to explain social learning of fear through observation and instruction. We also describe how observational and instructed fear is distinguished by involvement of additional neural systems implicated in social-emotional behavior, language and explicit memory, and propose a modified conditioning model to account for social fear learning. A better understanding of social fear learning promotes integration of biological principles of learning with cultural evolution.
ARTICLE UPDATE - Targeting abnormal neural circuits in mood and anxiety disorders: from the laboratory to the clinic.
Ressler KJ, Mayberg HS.
Nature Neuorscience, 10, 1116-1124
Recent decades have witnessed tremendous advances in the neuroscience of emotion, learning and memory, and in animal models for understanding depression and anxiety. This review focuses on new rationally designed psychiatric treatments derived from preclinical human and animal studies. Nonpharmacological treatments that affect disrupted emotion circuits include vagal nerve stimulation, rapid transcranial magnetic stimulation and deep brain stimulation, all borrowed from neurological interventions that attempt to target known pathological foci. Other approaches include drugs that are given in relation to specific learning events to enhance or disrupt endogenous emotional learning processes. Imaging data suggest that common regions of brain activation are targeted with pharmacological and somatic treatments as well as with the emotional learning in psychotherapy. Although many of these approaches are experimental, the rapidly developing understanding of emotional circuit regulation is likely to provide exciting and powerful future treatments for debilitating mood and anxiety disorders.
Nature Neuorscience, 10, 1116-1124
Recent decades have witnessed tremendous advances in the neuroscience of emotion, learning and memory, and in animal models for understanding depression and anxiety. This review focuses on new rationally designed psychiatric treatments derived from preclinical human and animal studies. Nonpharmacological treatments that affect disrupted emotion circuits include vagal nerve stimulation, rapid transcranial magnetic stimulation and deep brain stimulation, all borrowed from neurological interventions that attempt to target known pathological foci. Other approaches include drugs that are given in relation to specific learning events to enhance or disrupt endogenous emotional learning processes. Imaging data suggest that common regions of brain activation are targeted with pharmacological and somatic treatments as well as with the emotional learning in psychotherapy. Although many of these approaches are experimental, the rapidly developing understanding of emotional circuit regulation is likely to provide exciting and powerful future treatments for debilitating mood and anxiety disorders.
Thursday, August 23, 2007
ARTICLE UPDATE - EMuJoy: software for continuous measurement of perceived emotions in music.
Nagel F, Kopiez R, Grewe O, Altenmüller E.
Behavior Research Methods, 39, 283-290
An adequate study of emotions in music and film should be based on the real-time measurement of self-reported data using a continuous-response method. The recording system discussed in this article reflects two important aspects of such research: First, for a better comparison of results, experimental and technical standards for continuous measurement should be taken into account, and second, the recording system should be open to the inclusion of multimodal stimuli. In light of these two considerations, our article addresses four basic principles of the continuous measurement of emotions: (1) the dimensionality of the emotion space, (2) data acquisition (e.g., the synchronization of media and the self-reported data), (3) interface construction for emotional responses, and (4) the use of multiple stimulus modalities. Researcher-developed software (EMuJoy) is presented as a freeware solution for the continuous measurement of responses to different media, along with empirical data from the self-reports of 38 subjects listening to emotional music and viewing affective pictures.
Behavior Research Methods, 39, 283-290
An adequate study of emotions in music and film should be based on the real-time measurement of self-reported data using a continuous-response method. The recording system discussed in this article reflects two important aspects of such research: First, for a better comparison of results, experimental and technical standards for continuous measurement should be taken into account, and second, the recording system should be open to the inclusion of multimodal stimuli. In light of these two considerations, our article addresses four basic principles of the continuous measurement of emotions: (1) the dimensionality of the emotion space, (2) data acquisition (e.g., the synchronization of media and the self-reported data), (3) interface construction for emotional responses, and (4) the use of multiple stimulus modalities. Researcher-developed software (EMuJoy) is presented as a freeware solution for the continuous measurement of responses to different media, along with empirical data from the self-reports of 38 subjects listening to emotional music and viewing affective pictures.
ARTICLE UPDATE - Does remembering emotional items impair recall of same-emotion items?
Sison JA, Mather M.
Psychonomic Bulletin & Review, 14, 282-287
In the part-set cuing effect, cuing a subset of previously studied items impairs recall of the remaining noncued items. This experiment reveals that cuing participants with previously-studied emotional pictures (e.g., fear-evoking pictures of people) can impair recall of pictures involving the same emotion but different content (e.g., fear-evoking pictures of animals). This indicates that new events can be organized in memory using emotion as a grouping function to create associations. However, whether new information is organized in memory along emotional or nonemotional lines appears to be a flexible process that depends on people's current focus. Mentioning in the instructions that the pictures were either amusement- or fear-related led to memory impairment for pictures with the same emotion as cued pictures, whereas mentioning that the pictures depicted either animals or people led to memory impairment for pictures with the same type of actor.
Psychonomic Bulletin & Review, 14, 282-287
In the part-set cuing effect, cuing a subset of previously studied items impairs recall of the remaining noncued items. This experiment reveals that cuing participants with previously-studied emotional pictures (e.g., fear-evoking pictures of people) can impair recall of pictures involving the same emotion but different content (e.g., fear-evoking pictures of animals). This indicates that new events can be organized in memory using emotion as a grouping function to create associations. However, whether new information is organized in memory along emotional or nonemotional lines appears to be a flexible process that depends on people's current focus. Mentioning in the instructions that the pictures were either amusement- or fear-related led to memory impairment for pictures with the same emotion as cued pictures, whereas mentioning that the pictures depicted either animals or people led to memory impairment for pictures with the same type of actor.
ARTICLE UPDATE - Multidimensional normative ratings for the International Affective Picture System.
Libkuman TM, Otani H, Kern R, Viger SG, Novak N.
Behavior Research Methods, 39, 326-334
The purpose of the present investigation was to replicate and extend the International Affective Picture System norms (Ito, Cacioppo, & Lang, 1998; Lang, Bradley, & Cuthbert, 1999). These norms were developed to provide researchers with photographic slides that varied in emotional evocation, especially arousal and valence. In addition to collecting rating data on the dimensions of arousal and valence, we collected data on the dimensions of consequentiality, meaningfulness, familiarity, distinctiveness, and memorability. Furthermore, we collected ratings on the primary emotions of happiness, surprise, sadness, anger, disgust, and fear. A total of 1,302 participants were tested in small groups. The participants in each group rated a subset of 18 slides on 14 dimensions. Ratings were obtained on 703 slides. The means and standard deviations for all of the ratings are provided. We found our valence ratings to be similar to the previous norms. In contrast, our participants were more likely to rate the slides as less arousing than in the previous norms. The mean ratings on the remaining 12 dimensions were all below the midpoint of the 9-point Likert scale. However, sufficient variability in ratings across the slides indicates that selecting slides on the basis of these variables is feasible. Overall, the present ratings should allow investigators to use these norms for research purposes, especially in research dealing with the interrelationships among emotion and cognition. The means and standard deviations for emotions may be downloaded as an Excel spreadsheet from www.psychonomic.org/archive.
Behavior Research Methods, 39, 326-334
The purpose of the present investigation was to replicate and extend the International Affective Picture System norms (Ito, Cacioppo, & Lang, 1998; Lang, Bradley, & Cuthbert, 1999). These norms were developed to provide researchers with photographic slides that varied in emotional evocation, especially arousal and valence. In addition to collecting rating data on the dimensions of arousal and valence, we collected data on the dimensions of consequentiality, meaningfulness, familiarity, distinctiveness, and memorability. Furthermore, we collected ratings on the primary emotions of happiness, surprise, sadness, anger, disgust, and fear. A total of 1,302 participants were tested in small groups. The participants in each group rated a subset of 18 slides on 14 dimensions. Ratings were obtained on 703 slides. The means and standard deviations for all of the ratings are provided. We found our valence ratings to be similar to the previous norms. In contrast, our participants were more likely to rate the slides as less arousing than in the previous norms. The mean ratings on the remaining 12 dimensions were all below the midpoint of the 9-point Likert scale. However, sufficient variability in ratings across the slides indicates that selecting slides on the basis of these variables is feasible. Overall, the present ratings should allow investigators to use these norms for research purposes, especially in research dealing with the interrelationships among emotion and cognition. The means and standard deviations for emotions may be downloaded as an Excel spreadsheet from www.psychonomic.org/archive.
ARTICLE UPDATE - How emotions inform judgment and regulate thought
Clore GL, Huntsinger JR.
Trends in Cognitive Sciences, in press
Being happy or sad influences the content and style of thought. One explanation is that affect serves as information about the value of whatever comes to mind. Thus, when a person makes evaluative judgments or engages in a task, positive affect can enhance evaluations and empower potential responses. Rather than affect itself, the information conveyed by affect is crucial. Tests of the hypothesis find that affective influences can be made to disappear by changing the source to which the affect is attributed. In tasks, positive affect validates and negative affect invalidates accessible cognitions, leading to relational processing and item-specific processing, respectively. Positive affect is found to promote, and negative affect to inhibit, many textbook phenomena from cognitive psychology.
Trends in Cognitive Sciences, in press
Being happy or sad influences the content and style of thought. One explanation is that affect serves as information about the value of whatever comes to mind. Thus, when a person makes evaluative judgments or engages in a task, positive affect can enhance evaluations and empower potential responses. Rather than affect itself, the information conveyed by affect is crucial. Tests of the hypothesis find that affective influences can be made to disappear by changing the source to which the affect is attributed. In tasks, positive affect validates and negative affect invalidates accessible cognitions, leading to relational processing and item-specific processing, respectively. Positive affect is found to promote, and negative affect to inhibit, many textbook phenomena from cognitive psychology.
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