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.
Wednesday, October 31, 2007
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.
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