Kenntner-Mabiala R, Andreatta M, Wieser MJ, Mühlberger A, Pauli P.
Biological Psychology, in press
The influence of affect and attention on sensory and affective pain as well as on somatosensory evoked potentials in response to painful and nonpainful electrical stimuli was investigated in a single experimental design. Affect was induced by pictures from the International Affective Picture System; attention was manipulated by asking participants to focus attention either on the pictures or on the electrical stimuli. Sensory and affective pain ratings were generally lower during exposure to positive compared to negative and neutral pictures. Attention modulated only sensory pain ratings with lower ratings with an attention focus on pictures than with an attention focus on sensory pain. The N150 was modulated by picture valence, the P260 by picture arousal. Furthermore, the P260 was modulated by attention with highest amplitudes with an attention focus on the stimulus intensity. This study provides neurophysiological evidence that attention and affect have distinct effects on pain processing.
Friday, March 14, 2008
ARTICLE UPDATE - Viewing emotionally arousing compared to neutral pictures is associated with differential electrophysiological activity in early ("ea
Rigoulot S, Delplanque S, Despretz P, Defoort-Dhellemmes S, Honoré J, Sequeira H.
Brain Topography, in press
Recent findings from event-related potentials (ERPs) studies provided strong evidence that cen- trally presented emotional pictures could be used to assess affective processing. Moreover, several studies showed that emotionally charged stimuli may automatically attract attention even if these are not consciously identified. Indeed, such perceptive conditions can be compared to those typical of the peripheral vision, particularly known to have low spatial resolution capacities. The aim of the present study was to characterize at behavioral and neural levels the impact of emotional visual scenes presented in peripheral vision. Eighteen participants were asked to categorize neutral and unpleasant pictures presented at central (0 degrees ) and peripheral eccentricities (-30 and +30 degrees ) while ERPs were recorded from 63 electrodes. ERPs were analysed by means of spatio-temporal principal component analyses (PCA) in order to evaluate influences of the emotional content on ERP components for each spatial position (central vs. peripheral). Main results highlight that affective modulation of early ERP components exists for both centrally and peripherally presented pictures. These findings suggest that, for far peripheral eccentricities as for central vision, the brain engages specific resources to process emotional information.
Brain Topography, in press
Recent findings from event-related potentials (ERPs) studies provided strong evidence that cen- trally presented emotional pictures could be used to assess affective processing. Moreover, several studies showed that emotionally charged stimuli may automatically attract attention even if these are not consciously identified. Indeed, such perceptive conditions can be compared to those typical of the peripheral vision, particularly known to have low spatial resolution capacities. The aim of the present study was to characterize at behavioral and neural levels the impact of emotional visual scenes presented in peripheral vision. Eighteen participants were asked to categorize neutral and unpleasant pictures presented at central (0 degrees ) and peripheral eccentricities (-30 and +30 degrees ) while ERPs were recorded from 63 electrodes. ERPs were analysed by means of spatio-temporal principal component analyses (PCA) in order to evaluate influences of the emotional content on ERP components for each spatial position (central vs. peripheral). Main results highlight that affective modulation of early ERP components exists for both centrally and peripherally presented pictures. These findings suggest that, for far peripheral eccentricities as for central vision, the brain engages specific resources to process emotional information.
ARTICLE UPDATE - Affective Prime and Target Picture Processing: An ERP Analysis of Early and Late Interference Effects.
Flaisch T, Stockburger J, Schupp HT.
Brain Topography, in press
Viewing emotionally arousing compared to neutral pictures is associated with differential electrophysiological activity in early ("early posterior negativity", EPN), as well as later time-windows ("late positive potential", LPP). A previous study revealed that the EPN is reduced when the preceding prime picture was emotional. The present study explored whether sequential interference effects are specific for early processing stages or extend to later processing stages. Dense sensor ERPs were measured while subjects viewed a continuous stream of pleasant, neutral, and unpleasant pictures, presented for 660 ms each. Previous results were replicated in that emotional pictures were associated with enlarged EPN and LPP amplitudes compared to neutral pictures. Furthermore, the EPN to emotional and neutral pictures was reduced when preceded by pleasant prime pictures. The novel finding was that emotional compared to neutral prime pictures were associated with reduced LPP amplitudes to the subsequently presented picture irrespective of its emotional valence (pleasant, neutral, unpleasant). These results demonstrate sustained interference effects in serial picture presentations discussed within a framework of resource competition among successive pictures.
Brain Topography, in press
Viewing emotionally arousing compared to neutral pictures is associated with differential electrophysiological activity in early ("early posterior negativity", EPN), as well as later time-windows ("late positive potential", LPP). A previous study revealed that the EPN is reduced when the preceding prime picture was emotional. The present study explored whether sequential interference effects are specific for early processing stages or extend to later processing stages. Dense sensor ERPs were measured while subjects viewed a continuous stream of pleasant, neutral, and unpleasant pictures, presented for 660 ms each. Previous results were replicated in that emotional pictures were associated with enlarged EPN and LPP amplitudes compared to neutral pictures. Furthermore, the EPN to emotional and neutral pictures was reduced when preceded by pleasant prime pictures. The novel finding was that emotional compared to neutral prime pictures were associated with reduced LPP amplitudes to the subsequently presented picture irrespective of its emotional valence (pleasant, neutral, unpleasant). These results demonstrate sustained interference effects in serial picture presentations discussed within a framework of resource competition among successive pictures.
ARTICLE UPDATE - Immediate memory consequences of the effect of emotion on attention to pictures.
Talmi D, Anderson AK, Riggs L, Caplan JB, Moscovitch M.
Learning & Memory, 15, 172-182
Emotionally arousing stimuli are at once both highly attention grabbing and memorable. We examined whether emotional enhancement of memory (EEM) reflects an indirect effect of emotion on memory, mediated by enhanced attention to emotional items during encoding. We tested a critical prediction of the mediation hypothesis-that regions conjointly activated by emotion and attention would correlate with subsequent EEM. Participants were scanned with fMRI while they watched emotional or neutral pictures under instructions to attend to them a lot or a little, and were then given an immediate recognition test. A region in the left fusiform gyrus was activated by emotion, voluntary attention, and subsequent EEM. A functional network, different for each attention condition, connected this region and the amygdala, which was associated with emotion and EEM, but not with voluntary attention. These findings support an indirect cortical mediation account of immediate EEM that may complement a direct modulation model.
Learning & Memory, 15, 172-182
Emotionally arousing stimuli are at once both highly attention grabbing and memorable. We examined whether emotional enhancement of memory (EEM) reflects an indirect effect of emotion on memory, mediated by enhanced attention to emotional items during encoding. We tested a critical prediction of the mediation hypothesis-that regions conjointly activated by emotion and attention would correlate with subsequent EEM. Participants were scanned with fMRI while they watched emotional or neutral pictures under instructions to attend to them a lot or a little, and were then given an immediate recognition test. A region in the left fusiform gyrus was activated by emotion, voluntary attention, and subsequent EEM. A functional network, different for each attention condition, connected this region and the amygdala, which was associated with emotion and EEM, but not with voluntary attention. These findings support an indirect cortical mediation account of immediate EEM that may complement a direct modulation model.
ARTICLE UPDATE - Distinguishing specific sexual and general emotional effects in fMRI-Subcortical and cortical arousal during erotic picture viewing.
Walter M, Bermpohl F, Mouras H, Schiltz K, Tempelmann C, Rotte M, Heinze HJ, Bogerts B, Northoff G.
Neuroimage, in press
Sexual activity involves excitement with high arousal and pleasure as typical features of emotions. Brain activations specifically related to erotic feelings and those related to general emotional processing are therefore hard to disentangle. Using fMRI in 21 healthy subjects (11 males and 10 females), we investigated regions that show activations specifically related to the viewing of sexually intense pictures while controlling for general emotional arousal (GEA) or pleasure. Activations in the ventral striatum and hypothalamus were found to be modulated by the stimulus' specific sexual intensity (SSI) while activations in the anterior cingulate cortex were associated with an interaction between sexual intensity and emotional valence. In contrast, activation in other regions like the dorsomedial prefrontal cortex, the mediodorsal thalamus and the amygdala was associated only with a general emotional component during sexual arousal. No differences were found in these effects when comparing females and males. Our findings demonstrate for the first time neural differentiation between emotional and sexual components in the neural network underlying sexual arousal.
Neuroimage, in press
Sexual activity involves excitement with high arousal and pleasure as typical features of emotions. Brain activations specifically related to erotic feelings and those related to general emotional processing are therefore hard to disentangle. Using fMRI in 21 healthy subjects (11 males and 10 females), we investigated regions that show activations specifically related to the viewing of sexually intense pictures while controlling for general emotional arousal (GEA) or pleasure. Activations in the ventral striatum and hypothalamus were found to be modulated by the stimulus' specific sexual intensity (SSI) while activations in the anterior cingulate cortex were associated with an interaction between sexual intensity and emotional valence. In contrast, activation in other regions like the dorsomedial prefrontal cortex, the mediodorsal thalamus and the amygdala was associated only with a general emotional component during sexual arousal. No differences were found in these effects when comparing females and males. Our findings demonstrate for the first time neural differentiation between emotional and sexual components in the neural network underlying sexual arousal.
ARTICLE UPDATE - Neuromagnetic Activity During Recognition of Emotional Pictures.
Kissler J, Hauswald A.
Brain Topography, in press
Recently studied [Symbol: see text]old' stimuli lead to larger frontal and parietal ERP responses than [Symbol: see text]new' stimuli. The present experiment investigated the neuromagnetic correlates (MEG) of this [Symbol: see text]old-new' effect and its modulation by emotional stimulus content. Highly arousing pleasant, highly arousing unpleasant and un-arousing neutral photographs were presented to the participants with the instruction to memorize them. They were later re-presented together with new photographs in an old-new decision task. In line with previous ERP studies, a long-lasting old-new effect (350-700 ms) was found. Independently, an emotion effect also occurred, as reflected in a, particularly left temporal, activity increase for emotional pictures between 450 and 580 ms. Moreover, only for the pleasant pictures did the early part of the old-new effect, which is thought to reflect familiarity based recognition processes, interact with picture content: The old-new effect for pleasant pictures in frontal regions was larger than the one for neutral or unpleasant pictures between 350 and 450 ms. In parallel, subjects' responses were accelerated towards and biased in favour of classifying pleasant pictures as old. However, when false alarm rate was taken into account, there was no significant effect of emotional content on recognition accuracy. In sum, this MEG study demonstrates an effect of particularly pleasant emotional content on recognition memory which may be mediated by a familiarity based process.
Brain Topography, in press
Recently studied [Symbol: see text]old' stimuli lead to larger frontal and parietal ERP responses than [Symbol: see text]new' stimuli. The present experiment investigated the neuromagnetic correlates (MEG) of this [Symbol: see text]old-new' effect and its modulation by emotional stimulus content. Highly arousing pleasant, highly arousing unpleasant and un-arousing neutral photographs were presented to the participants with the instruction to memorize them. They were later re-presented together with new photographs in an old-new decision task. In line with previous ERP studies, a long-lasting old-new effect (350-700 ms) was found. Independently, an emotion effect also occurred, as reflected in a, particularly left temporal, activity increase for emotional pictures between 450 and 580 ms. Moreover, only for the pleasant pictures did the early part of the old-new effect, which is thought to reflect familiarity based recognition processes, interact with picture content: The old-new effect for pleasant pictures in frontal regions was larger than the one for neutral or unpleasant pictures between 350 and 450 ms. In parallel, subjects' responses were accelerated towards and biased in favour of classifying pleasant pictures as old. However, when false alarm rate was taken into account, there was no significant effect of emotional content on recognition accuracy. In sum, this MEG study demonstrates an effect of particularly pleasant emotional content on recognition memory which may be mediated by a familiarity based process.
Friday, March 07, 2008
ARTICLE UPDATE - Incidental encoding of emotional pictures: Affective bias studied through event related brain potentials.
Tapia M, Carretié L, Sierra B, Mercado F.
International Journal of Psychophysiology, in press
Emotional stimuli are better remembered than neutral stimuli. Most of the studies taking into account this emotional bias refer to explicit memory, use behavioral measures of the recall and predict better recall of negative stimuli. The few studies taking into account implicit memory and the valence emotional dimension are inconclusive on the effect of the stimulus' emotional valence. In the present study, 120 pictures (30 positive, 30 negative, 30 relaxing and 30 neutral) were shown to, and assessed by, 28 participants (study phase). Subsequently, event related brain potentials (ERPs) were recorded during the presentation of 120 new (shown for the first time) and 120 old (already shown in the study phase) pictures (test phase). No explicit instructions or clues related to recovery were given to participants, and a distractor task was employed, in order to maintain implicit the memory assessment. As expected from other studies' data, our results showed that old stimuli elicited an enhanced late positive component 450 ms after stimulus onset (repetition effect). Moreover, this effect was modulated by the stimuli's emotional valence, since the most positively valenced stimuli were associated with a decreased repetition effect with respect to the most negatively valenced stimuli. This effect was located at ventromedial prefrontal cortex. These results suggest the existence of a valence-mediated bias in implicit memory.
International Journal of Psychophysiology, in press
Emotional stimuli are better remembered than neutral stimuli. Most of the studies taking into account this emotional bias refer to explicit memory, use behavioral measures of the recall and predict better recall of negative stimuli. The few studies taking into account implicit memory and the valence emotional dimension are inconclusive on the effect of the stimulus' emotional valence. In the present study, 120 pictures (30 positive, 30 negative, 30 relaxing and 30 neutral) were shown to, and assessed by, 28 participants (study phase). Subsequently, event related brain potentials (ERPs) were recorded during the presentation of 120 new (shown for the first time) and 120 old (already shown in the study phase) pictures (test phase). No explicit instructions or clues related to recovery were given to participants, and a distractor task was employed, in order to maintain implicit the memory assessment. As expected from other studies' data, our results showed that old stimuli elicited an enhanced late positive component 450 ms after stimulus onset (repetition effect). Moreover, this effect was modulated by the stimuli's emotional valence, since the most positively valenced stimuli were associated with a decreased repetition effect with respect to the most negatively valenced stimuli. This effect was located at ventromedial prefrontal cortex. These results suggest the existence of a valence-mediated bias in implicit memory.
ARTICLE UPDATE - Affective neuroscience of pleasure: reward in humans and animals.
Berridge KC, Kringelbach ML.
Psychopharmacology, in press
INTRODUCTION: Pleasure and reward are generated by brain circuits that are largely shared between humans and other animals. DISCUSSION: Here, we survey some fundamental topics regarding pleasure mechanisms and explicitly compare humans and animals. CONCLUSION: Topics surveyed include liking, wanting, and learning components of reward; brain coding versus brain causing of reward; subjective pleasure versus objective hedonic reactions; roles of orbitofrontal cortex and related cortex regions; subcortical hedonic hotspots for pleasure generation; reappraisals of dopamine and pleasure-electrode controversies; and the relation of pleasure to happiness.
Psychopharmacology, in press
INTRODUCTION: Pleasure and reward are generated by brain circuits that are largely shared between humans and other animals. DISCUSSION: Here, we survey some fundamental topics regarding pleasure mechanisms and explicitly compare humans and animals. CONCLUSION: Topics surveyed include liking, wanting, and learning components of reward; brain coding versus brain causing of reward; subjective pleasure versus objective hedonic reactions; roles of orbitofrontal cortex and related cortex regions; subcortical hedonic hotspots for pleasure generation; reappraisals of dopamine and pleasure-electrode controversies; and the relation of pleasure to happiness.
ARTICLE UPDATE - Valuating other people's emotional face expression: A combined functional magnetic resonance imaging and electroencephalography study
Seitz RJ, Schäfer R, Scherfeld D, Friederichs S, Popp K, Wittsack HJ, Azari NP, Franz M.
Neuroscience, in press
Reading the facial expression of other people is a fundamental skill for social interaction. Human facial expressions of emotions are readily recognized but may also evoke the same experiential emotional state in the observer. We used event-related functional magnetic resonance imaging and multi-channel electroencephalography to determine in 14 right-handed healthy volunteers (29+/-6 years) which brain structures mediate the perception of such a shared experiential emotional state. Statistical parametric mapping showed that an area in the dorsal medial frontal cortex was specifically activated during the perception of emotions that reflected the seen happy and sad emotional face expressions. This area mapped to the pre-supplementary motor area which plays a central role in control of behavior. Low resolution brain electromagnetic tomography-based analysis of the encephalographic data revealed that the activation was detected 100 ms after face presentation onset lasting until 740 ms. Our observation substantiates recently emerging evidence suggesting that the subjective perception of an experiential emotional state-empathy-is mediated by the involvement of the dorsal medial frontal cortex.
Neuroscience, in press
Reading the facial expression of other people is a fundamental skill for social interaction. Human facial expressions of emotions are readily recognized but may also evoke the same experiential emotional state in the observer. We used event-related functional magnetic resonance imaging and multi-channel electroencephalography to determine in 14 right-handed healthy volunteers (29+/-6 years) which brain structures mediate the perception of such a shared experiential emotional state. Statistical parametric mapping showed that an area in the dorsal medial frontal cortex was specifically activated during the perception of emotions that reflected the seen happy and sad emotional face expressions. This area mapped to the pre-supplementary motor area which plays a central role in control of behavior. Low resolution brain electromagnetic tomography-based analysis of the encephalographic data revealed that the activation was detected 100 ms after face presentation onset lasting until 740 ms. Our observation substantiates recently emerging evidence suggesting that the subjective perception of an experiential emotional state-empathy-is mediated by the involvement of the dorsal medial frontal cortex.
ARTICLE UPDATE - Emotional valence and arousal interact in attentional control.
Jefferies LN, Smilek D, Eich E, Enns JT.
Psychological Science, 19, 290-295
A recent study demonstrated that observers' ability to identify targets in a rapid visual sequence was enhanced when they simultaneously listened to happy music. In the study reported here, we examined how the emotion-attention relationship is influenced by changes in both mood valence (negative vs. positive) and arousal (low vs. high). We used a standard induction procedure to generate calm, happy, sad, and anxious moods in participants. Results for an attentional blink task showed no differences in first-target accuracy, but second-target accuracy was highest for participants with low arousal and negative affect (sad), lowest for those with strong arousal and negative affect (anxious), and intermediate for those with positive affect regardless of their arousal (calm, happy). We discuss implications of this valence-arousal interaction for the control of visual attention.
Psychological Science, 19, 290-295
A recent study demonstrated that observers' ability to identify targets in a rapid visual sequence was enhanced when they simultaneously listened to happy music. In the study reported here, we examined how the emotion-attention relationship is influenced by changes in both mood valence (negative vs. positive) and arousal (low vs. high). We used a standard induction procedure to generate calm, happy, sad, and anxious moods in participants. Results for an attentional blink task showed no differences in first-target accuracy, but second-target accuracy was highest for participants with low arousal and negative affect (sad), lowest for those with strong arousal and negative affect (anxious), and intermediate for those with positive affect regardless of their arousal (calm, happy). We discuss implications of this valence-arousal interaction for the control of visual attention.
Friday, February 29, 2008
ARTICLE UPDATE - Seeing the pain of others while being in pain: A laser-evoked potentials study.
Valeriani M, Betti V, Le Pera D, De Armas L, Miliucci R, Restuccia D, Avenanti A, Aglioti SM.
Neuroimage, in press
Seeing actions, emotions and feelings of other individuals may activate resonant mechanisms that allow the empathic understanding of others' states. Being crucial for implementing pro-social behaviors, empathy is considered as inherently altruistic. Here we explored whether the personal experience of pain make individuals less inclined to share others' pain. We used laser-evoked potentials (LEPs) to explore whether observation of painful or non-noxious stimuli delivered to a stranger model induced any modulation in the pain system of onlookers who were suffering from pain induced by the laser stimuli. After LEPs recording, participants rated intensity and unpleasantness of the laser pain, and of the pain induced by the movie in themselves and in the model. Mere observation of needles penetrating the model's hand brought about a specific reduction of the N1/P1 LEP component, related to the activation of somatic nodes of the pain matrix. Such reduction is stronger in onlookers who rated the pain intensity induced by the pain movie as higher in themselves and lower in the model. Conversely, the N2a-P2 component, supposedly associated to affective pain qualities, did not show any specific modulation during observation of others' pain. Thus, viewing 'flesh and bone' pain in others specifically modulates neural activity in the pain matrix sensory node. Moreover, this socially-derived inhibitory effect is correlated with the intensity of the pain attributed to self rather than to others suggesting that being in pain may bias the empathic relation with stranger models towards self-centred instead than other-related stances.
Neuroimage, in press
Seeing actions, emotions and feelings of other individuals may activate resonant mechanisms that allow the empathic understanding of others' states. Being crucial for implementing pro-social behaviors, empathy is considered as inherently altruistic. Here we explored whether the personal experience of pain make individuals less inclined to share others' pain. We used laser-evoked potentials (LEPs) to explore whether observation of painful or non-noxious stimuli delivered to a stranger model induced any modulation in the pain system of onlookers who were suffering from pain induced by the laser stimuli. After LEPs recording, participants rated intensity and unpleasantness of the laser pain, and of the pain induced by the movie in themselves and in the model. Mere observation of needles penetrating the model's hand brought about a specific reduction of the N1/P1 LEP component, related to the activation of somatic nodes of the pain matrix. Such reduction is stronger in onlookers who rated the pain intensity induced by the pain movie as higher in themselves and lower in the model. Conversely, the N2a-P2 component, supposedly associated to affective pain qualities, did not show any specific modulation during observation of others' pain. Thus, viewing 'flesh and bone' pain in others specifically modulates neural activity in the pain matrix sensory node. Moreover, this socially-derived inhibitory effect is correlated with the intensity of the pain attributed to self rather than to others suggesting that being in pain may bias the empathic relation with stranger models towards self-centred instead than other-related stances.
ARTICLE UPDATE - Understanding the Role of Emotion in Sense-making. A Semiotic Psychoanalytic Oriented Perspective.
Salvatore S, Venuleo C.
Integrative Psychological and Behavioral Science, 42, 32-46
We propose a model of emotion grounded on Ignacio Matte Blanco's theory of the unconscious. According to this conceptualization, emotion is a generalized representation of the social context actors are involved in. We discuss how this model can help to better understand the sensemaking processes. For this purpose we present a hierarchical model of sensemaking based on the distinction between significance-the content of the sign-and sense-the psychological value of the act of producing the sign in the given contingence of the social exchange. According to this model, emotion categorization produces the frame of sense regulating the interpretation of the sense of the signs, therefore creating the psychological value of the sensemaking.
Integrative Psychological and Behavioral Science, 42, 32-46
We propose a model of emotion grounded on Ignacio Matte Blanco's theory of the unconscious. According to this conceptualization, emotion is a generalized representation of the social context actors are involved in. We discuss how this model can help to better understand the sensemaking processes. For this purpose we present a hierarchical model of sensemaking based on the distinction between significance-the content of the sign-and sense-the psychological value of the act of producing the sign in the given contingence of the social exchange. According to this model, emotion categorization produces the frame of sense regulating the interpretation of the sense of the signs, therefore creating the psychological value of the sensemaking.
ARTICLE UPDATE - The power of the word may reside in the power of affect.
Panksepp J.
Integrative Psychological and Behavioral Science, 42, 47-55
This commentary on Dan Shanahan's, A New View of Language, Emotion and the Brain, basically agrees with an emotion-based view of the evolutionary and developmental basis of language acquisition. It provides a supplementary neuroscience perspective that is more deeply affective and epigenetic in the sense that all claims about neocortically-based language modules need to be tempered by the existing genetic evidence as well as the robust neuroscience evidence that the cortex resembles random-access-memory space, a tabula rasa upon which epigenetic and learning processes create functional networks. The transition from non-linguistic creatures to linguistic ones may have required the conjunction of social-affective brain mechanisms, morphological changes in the articulatory apparatus, an abundance of cross-modal cortical processing ability, and the initial urge to communicate in coordinate prosodic gestural and vocal ways, which may have been more poetic and musical than current propositional language. There may be no language instinct that is independent of these evolutionary pre-adaptations.
Integrative Psychological and Behavioral Science, 42, 47-55
This commentary on Dan Shanahan's, A New View of Language, Emotion and the Brain, basically agrees with an emotion-based view of the evolutionary and developmental basis of language acquisition. It provides a supplementary neuroscience perspective that is more deeply affective and epigenetic in the sense that all claims about neocortically-based language modules need to be tempered by the existing genetic evidence as well as the robust neuroscience evidence that the cortex resembles random-access-memory space, a tabula rasa upon which epigenetic and learning processes create functional networks. The transition from non-linguistic creatures to linguistic ones may have required the conjunction of social-affective brain mechanisms, morphological changes in the articulatory apparatus, an abundance of cross-modal cortical processing ability, and the initial urge to communicate in coordinate prosodic gestural and vocal ways, which may have been more poetic and musical than current propositional language. There may be no language instinct that is independent of these evolutionary pre-adaptations.
ARTICLE UPDATE - Differential effects of object-based attention on evoked potentials to fearful and disgusted faces.
Isabel M. Santos, Jaime Iglesias, Ela I. Olivares and Andrew W. Young
Neuropsychologia, in press
Event-related potentials (ERPs) were used to investigate the role of attention on the processing of facial expressions of fear and disgust. Stimuli consisted of overlapping pictures of a face and a house. Participants had to monitor repetitions of faces or houses, in separate blocks of trials, so that object-based attention was manipulated while spatial attention was kept constant. Faces varied in expression and could be either fearful or neutral (in the fear condition) or disgusted or neutral (in the disgust condition). When attending to faces, participants were required to signal repetitions of the same person, with the facial expressions being completely irrelevant to the task. Different effects of selective attention and different patterns of brain activity were observed for faces with fear and disgust expressions. Results indicated that the perception of fear from faces is gated by selective attention at early latencies, whereas a sustained positivity for fearful faces compared to neutral faces emerged around 160ms at central-parietal sites, independent of selective attention. In the case of disgust, ERP differences began only around 160ms after stimulus onset, and only after 480ms was the perception of disgust modulated by attention allocation. Results are interpreted in terms of different neural mechanisms for the perception of fear and disgust and related to the functional significance of these two emotions for the survival of the organism.
Neuropsychologia, in press
Event-related potentials (ERPs) were used to investigate the role of attention on the processing of facial expressions of fear and disgust. Stimuli consisted of overlapping pictures of a face and a house. Participants had to monitor repetitions of faces or houses, in separate blocks of trials, so that object-based attention was manipulated while spatial attention was kept constant. Faces varied in expression and could be either fearful or neutral (in the fear condition) or disgusted or neutral (in the disgust condition). When attending to faces, participants were required to signal repetitions of the same person, with the facial expressions being completely irrelevant to the task. Different effects of selective attention and different patterns of brain activity were observed for faces with fear and disgust expressions. Results indicated that the perception of fear from faces is gated by selective attention at early latencies, whereas a sustained positivity for fearful faces compared to neutral faces emerged around 160ms at central-parietal sites, independent of selective attention. In the case of disgust, ERP differences began only around 160ms after stimulus onset, and only after 480ms was the perception of disgust modulated by attention allocation. Results are interpreted in terms of different neural mechanisms for the perception of fear and disgust and related to the functional significance of these two emotions for the survival of the organism.
Thursday, February 21, 2008
ARTICLE UPDATE - Emotional scenes in peripheral vision: Selective orienting and gist processing, but not content identification.
Calvo MG, Nummenmaa L, Hyönä J.
Emotion, 8, 68-80
Emotional-neutral pairs of visual scenes were presented peripherally (with their inner edges 5.2 degrees away from fixation) as primes for 150 to 900 ms, followed by a centrally presented recognition probe scene, which was either identical in specific content to one of the primes or related in general content and affective valence. Results indicated that (a) if no foveal fixations on the primes were allowed, the false alarm rate for emotional probes was increased; (b) hit rate and sensitivity (A') were higher for emotional than for neutral probes only when a fixation was possible on only one prime; and (c) emotional scenes were more likely to attract the first fixation than neutral scenes. It is concluded that the specific content of emotional or neutral scenes is not processed in peripheral vision. Nevertheless, a coarse impression of emotional scenes may be extracted, which then leads to selective attentional orienting or--in the absence of overt attention--causes false alarms for related probes.
Emotion, 8, 68-80
Emotional-neutral pairs of visual scenes were presented peripherally (with their inner edges 5.2 degrees away from fixation) as primes for 150 to 900 ms, followed by a centrally presented recognition probe scene, which was either identical in specific content to one of the primes or related in general content and affective valence. Results indicated that (a) if no foveal fixations on the primes were allowed, the false alarm rate for emotional probes was increased; (b) hit rate and sensitivity (A') were higher for emotional than for neutral probes only when a fixation was possible on only one prime; and (c) emotional scenes were more likely to attract the first fixation than neutral scenes. It is concluded that the specific content of emotional or neutral scenes is not processed in peripheral vision. Nevertheless, a coarse impression of emotional scenes may be extracted, which then leads to selective attentional orienting or--in the absence of overt attention--causes false alarms for related probes.
ARTICLE UPDATE - Affective learning increases sensitivity to graded emotional faces.
Lim SL, Pessoa L.
Emotion, 8, 96-103
How does the affective significance of emotional faces affect perceptual decisions? We manipulated affective significance by pairing 100% fearful faces with aversive electrical stimulation and hypothesized that increasing the significance of a stimulus via its prior history would lead to enhanced processing. After fear conditioning, participants viewed graded emotional faces that ranged from neutral to fearful. Faces were shown either in a color that was previously paired with shock or a color not paired with shock during conditioning. Increases in the frequency of "fearful" responses for faces shown in the shock-paired color were most robust for faces at intermediate intensity levels (40-60% fearful). Psychometric fits to the data revealed significant increased sensitivity for shock-paired relative to unpaired faces. Thus, despite identical physical features for shock-paired and unpaired stimuli (aside from the color, which was counterbalanced), more frequent (and faster) "fearful" responses were made when participants viewed affectively significant stimuli.
Emotion, 8, 96-103
How does the affective significance of emotional faces affect perceptual decisions? We manipulated affective significance by pairing 100% fearful faces with aversive electrical stimulation and hypothesized that increasing the significance of a stimulus via its prior history would lead to enhanced processing. After fear conditioning, participants viewed graded emotional faces that ranged from neutral to fearful. Faces were shown either in a color that was previously paired with shock or a color not paired with shock during conditioning. Increases in the frequency of "fearful" responses for faces shown in the shock-paired color were most robust for faces at intermediate intensity levels (40-60% fearful). Psychometric fits to the data revealed significant increased sensitivity for shock-paired relative to unpaired faces. Thus, despite identical physical features for shock-paired and unpaired stimuli (aside from the color, which was counterbalanced), more frequent (and faster) "fearful" responses were made when participants viewed affectively significant stimuli.
ARTICLE UPDATE - Affective flexibility: evaluative processing goals shape amygdala activity.
Cunningham WA, Van Bavel JJ, Johnsen IR.
Psychological Science, 19, 152-160
Although early research implicated the amygdala in automatic processing of negative information, more recent research suggests that it plays a more general role in processing the motivational relevance of various stimuli, suggesting that the relation between valence and amygdala activation may depend on contextual goals. This study provides experimental evidence that the relation between valence and amygdala activity is dynamically modulated by evaluative goals. During functional magnetic resonance imaging, participants evaluated the positive, negative, or overall (positive plus negative) aspects of famous people. When participants were providing overall evaluations, both positive and negative names were associated with amygdala activation. When they were evaluating positivity, positive names were associated with amygdala activity, and when they were evaluating negativity, negative names were associated with amygdala activity. Evidence for a negativity bias was found; modulation was more pronounced for positive than for negative information. These data suggest that the amygdala flexibly processes motivationally relevant evaluative information in accordance with current processing goals, but processes negative information less flexibly than positive information.
Psychological Science, 19, 152-160
Although early research implicated the amygdala in automatic processing of negative information, more recent research suggests that it plays a more general role in processing the motivational relevance of various stimuli, suggesting that the relation between valence and amygdala activation may depend on contextual goals. This study provides experimental evidence that the relation between valence and amygdala activity is dynamically modulated by evaluative goals. During functional magnetic resonance imaging, participants evaluated the positive, negative, or overall (positive plus negative) aspects of famous people. When participants were providing overall evaluations, both positive and negative names were associated with amygdala activation. When they were evaluating positivity, positive names were associated with amygdala activity, and when they were evaluating negativity, negative names were associated with amygdala activity. Evidence for a negativity bias was found; modulation was more pronounced for positive than for negative information. These data suggest that the amygdala flexibly processes motivationally relevant evaluative information in accordance with current processing goals, but processes negative information less flexibly than positive information.
ARTICLE UPDATE - Neural activities for negative priming with affective stimuli: An fMRI study.
Leung KK, Lee TM, Xiao Z, Wang Z, Zhang JX, Yip PS, Li LS.
Neuropsychology, in press
Negative priming refers to the slowing down in reaction time to a stimulus that is either the same as, or related to, a distracting stimulus that has been ignored by people in an immediately preceding trial. It can be used as an index to examine the extent to which people are able to disengage attention or even ignore a distracting stimulus. In this fMRI study, with healthy Mandarin-speaking Chinese participants, we replicated the basic negative priming effect with affectively neutral words. Negative priming was associated with increased activities in the anterior cingulate cortex and the insula, a result that supports the inhibition account of negative priming. We observed that the negative priming effect was attenuated by negative affective words, relative to neutral words, suggesting that subjects' inhibition of negative information was compromised. Such attenuation of negative priming by negative affective words was associated with increased activities in the ventrolateral and medial frontal regions, the hippocampus, and supplementary motor areas. These observations indicate that specific frontal and subcortical regions take part in attention orientation toward negative-affect information.
Neuropsychology, in press
Negative priming refers to the slowing down in reaction time to a stimulus that is either the same as, or related to, a distracting stimulus that has been ignored by people in an immediately preceding trial. It can be used as an index to examine the extent to which people are able to disengage attention or even ignore a distracting stimulus. In this fMRI study, with healthy Mandarin-speaking Chinese participants, we replicated the basic negative priming effect with affectively neutral words. Negative priming was associated with increased activities in the anterior cingulate cortex and the insula, a result that supports the inhibition account of negative priming. We observed that the negative priming effect was attenuated by negative affective words, relative to neutral words, suggesting that subjects' inhibition of negative information was compromised. Such attenuation of negative priming by negative affective words was associated with increased activities in the ventrolateral and medial frontal regions, the hippocampus, and supplementary motor areas. These observations indicate that specific frontal and subcortical regions take part in attention orientation toward negative-affect information.
ARTICLE UPDATE - The pupil as a measure of emotional arousal and autonomic activation.
Bradley MM, Miccoli L, Escrig MA, Lang PJ.
Psychophysiology, in press
Pupil diameter was monitored during picture viewing to assess effects of hedonic valence and emotional arousal on pupillary responses. Autonomic activity (heart rate and skin conductance) was concurrently measured to determine whether pupillary changes are mediated by parasympathetic or sympathetic activation. Following an initial light reflex, pupillary changes were larger when viewing emotionally arousing pictures, regardless of whether these were pleasant or unpleasant. Pupillary changes during picture viewing covaried with skin conductance change, supporting the interpretation that sympathetic nervous system activity modulates these changes in the context of affective picture viewing. Taken together, the data provide strong support for the hypothesis that the pupil's response during affective picture viewing reflects emotional arousal associated with increased sympathetic activity.
Psychophysiology, in press
Pupil diameter was monitored during picture viewing to assess effects of hedonic valence and emotional arousal on pupillary responses. Autonomic activity (heart rate and skin conductance) was concurrently measured to determine whether pupillary changes are mediated by parasympathetic or sympathetic activation. Following an initial light reflex, pupillary changes were larger when viewing emotionally arousing pictures, regardless of whether these were pleasant or unpleasant. Pupillary changes during picture viewing covaried with skin conductance change, supporting the interpretation that sympathetic nervous system activity modulates these changes in the context of affective picture viewing. Taken together, the data provide strong support for the hypothesis that the pupil's response during affective picture viewing reflects emotional arousal associated with increased sympathetic activity.
ARTICLE UPDATE - The use of aftereffects in the study of relationships among emotion categories.
Rutherford MD, Chattha HM, Krysko KM.
Journal of Experimental Psychology: Human Perception & Performance, 34, 27-40
The perception of visual aftereffects has been long recognized, and these aftereffects reveal a relationship between perceptual categories. Thus, emotional expression aftereffects can be used to map the categorical relationships among emotion percepts. One might expect a symmetric relationship among categories, but an evolutionary, functional perspective predicts an asymmetrical relationship. In a series of 7 experiments, the authors tested these predictions. Participants fixated on a facial expression, then briefly viewed a neutral expression, then reported the apparent facial expression of the 2nd image. Experiment 1 revealed that happy and sad are opposites of one another; each evokes the other as an aftereffect. The 2nd and 3rd experiments reveal that fixating on any negative emotions yields an aftereffect perceived as happy, whereas fixating on a happy face results in the perception of a sad aftereffect. This suggests an asymmetric relationship among categories. Experiments 4-7 explored the mechanism driving this effect. The evolutionary and functional explanations for the category asymmetry are discussed.
Journal of Experimental Psychology: Human Perception & Performance, 34, 27-40
The perception of visual aftereffects has been long recognized, and these aftereffects reveal a relationship between perceptual categories. Thus, emotional expression aftereffects can be used to map the categorical relationships among emotion percepts. One might expect a symmetric relationship among categories, but an evolutionary, functional perspective predicts an asymmetrical relationship. In a series of 7 experiments, the authors tested these predictions. Participants fixated on a facial expression, then briefly viewed a neutral expression, then reported the apparent facial expression of the 2nd image. Experiment 1 revealed that happy and sad are opposites of one another; each evokes the other as an aftereffect. The 2nd and 3rd experiments reveal that fixating on any negative emotions yields an aftereffect perceived as happy, whereas fixating on a happy face results in the perception of a sad aftereffect. This suggests an asymmetric relationship among categories. Experiments 4-7 explored the mechanism driving this effect. The evolutionary and functional explanations for the category asymmetry are discussed.
ARTICLE UPDATE - The emotional memory effect: differential processing or item distinctiveness?
Schmidt SR, Saari B.
Memory & Cognition, 35, 1905-1916
A color-naming task was followed by incidental free recall to investigate how emotional words affect attention and memory. We compared taboo, nonthreatening negative-affect, and neutral words across three experiments. As compared with neutral words, taboo words led to longer color-naming times and better memory in both within- and between-subjects designs. Color naming of negative-emotion nontaboo words was slower than color naming of neutral words only during block presentation and at relatively short interstimulus intervals (ISIs). The nontaboo emotion words were remembered better than neutral words following blocked and random presentation and at both long and short ISIs, but only in mixed-list designs. Our results support multifactor theories of the effects of emotion on attention and memory. As compared with neutral words, threatening stimuli received increased attention, poststimulus elaboration, and benefit from item distinctiveness, whereas nonthreatening emotional stimuli benefited only from increased item distinctiveness.
Memory & Cognition, 35, 1905-1916
A color-naming task was followed by incidental free recall to investigate how emotional words affect attention and memory. We compared taboo, nonthreatening negative-affect, and neutral words across three experiments. As compared with neutral words, taboo words led to longer color-naming times and better memory in both within- and between-subjects designs. Color naming of negative-emotion nontaboo words was slower than color naming of neutral words only during block presentation and at relatively short interstimulus intervals (ISIs). The nontaboo emotion words were remembered better than neutral words following blocked and random presentation and at both long and short ISIs, but only in mixed-list designs. Our results support multifactor theories of the effects of emotion on attention and memory. As compared with neutral words, threatening stimuli received increased attention, poststimulus elaboration, and benefit from item distinctiveness, whereas nonthreatening emotional stimuli benefited only from increased item distinctiveness.
ARTICLE UPDATE - The automaticity of emotion recognition.
Tracy JL, Robins RW.
Emotion, 8, 81-95
Evolutionary accounts of emotion typically assume that humans evolved to quickly and efficiently recognize emotion expressions because these expressions convey fitness-enhancing messages. The present research tested this assumption in 2 studies. Specifically, the authors examined (a) how quickly perceivers could recognize expressions of anger, contempt, disgust, embarrassment, fear, happiness, pride, sadness, shame, and surprise; (b) whether accuracy is improved when perceivers deliberate about each expression's meaning (vs. respond as quickly as possible); and (c) whether accurate recognition can occur under cognitive load. Across both studies, perceivers quickly and efficiently (i.e., under cognitive load) recognized most emotion expressions, including the self-conscious emotions of pride, embarrassment, and shame. Deliberation improved accuracy in some cases, but these improvements were relatively small. Discussion focuses on the implications of these findings for the cognitive processes underlying emotion recognition.
Emotion, 8, 81-95
Evolutionary accounts of emotion typically assume that humans evolved to quickly and efficiently recognize emotion expressions because these expressions convey fitness-enhancing messages. The present research tested this assumption in 2 studies. Specifically, the authors examined (a) how quickly perceivers could recognize expressions of anger, contempt, disgust, embarrassment, fear, happiness, pride, sadness, shame, and surprise; (b) whether accuracy is improved when perceivers deliberate about each expression's meaning (vs. respond as quickly as possible); and (c) whether accurate recognition can occur under cognitive load. Across both studies, perceivers quickly and efficiently (i.e., under cognitive load) recognized most emotion expressions, including the self-conscious emotions of pride, embarrassment, and shame. Deliberation improved accuracy in some cases, but these improvements were relatively small. Discussion focuses on the implications of these findings for the cognitive processes underlying emotion recognition.
ARTICLE UPDATE - Modulations of the electrophysiological response to pleasant stimuli by cognitive reappraisal.
Krompinger JW, Moser JS, Simons RF.
Emotion, 8, 132-137
Research indicates that individuals successfully regulate their emotions to negatively valenced stimuli using cognitive, antecedent-focused techniques (cf. Gross, 1998). Event-related potential studies have elucidated candidate neural correlates, particularly modulations of the late positive potential (LPP) to index emotion regulation processes. The present study attempted to extend prior demonstrations of emotion regulation effects on the LPP to the domain of positively valenced stimuli. Twenty participants completed a blocked emotion regulation task: The first block consisted of passively viewing pleasant and neutral pictures, whereas the last two blocks consisted of either decreasing or increasing emotions to pleasant pictures. Results replicated our previous findings with negatively valenced stimuli, demonstrating an attenuated LPP during decrease instructions and no effect of increase instructions. Modulation of the ERP as a function of instruction was most prominent during the positive-going slow-wave time window of the LPP, indicating that attentional resources allocated to the perceptual processing of pleasant stimuli may be manipulated using emotion regulation strategies.
Emotion, 8, 132-137
Research indicates that individuals successfully regulate their emotions to negatively valenced stimuli using cognitive, antecedent-focused techniques (cf. Gross, 1998). Event-related potential studies have elucidated candidate neural correlates, particularly modulations of the late positive potential (LPP) to index emotion regulation processes. The present study attempted to extend prior demonstrations of emotion regulation effects on the LPP to the domain of positively valenced stimuli. Twenty participants completed a blocked emotion regulation task: The first block consisted of passively viewing pleasant and neutral pictures, whereas the last two blocks consisted of either decreasing or increasing emotions to pleasant pictures. Results replicated our previous findings with negatively valenced stimuli, demonstrating an attenuated LPP during decrease instructions and no effect of increase instructions. Modulation of the ERP as a function of instruction was most prominent during the positive-going slow-wave time window of the LPP, indicating that attentional resources allocated to the perceptual processing of pleasant stimuli may be manipulated using emotion regulation strategies.
Tuesday, February 12, 2008
ARTICLE UPDATE - Learning affective values for faces is expressed in amygdala and fusiform gyrus
Predrag Petrovic, Raffael Kalisch, Mathias Pessiglione, Tania Singer and Raymond J. Dolan
Social Cognitive and Affective Neuroscience, in press
To monitor the environment for social threat humans must build affective evaluations of others. These evaluations are malleable and to a high degree shaped by responses engendered by specific social encounters. The precise neuronal mechanism by which these evaluations are constructed is poorly understood. We tested a hypothesis that conjoint activity in amygdala and fusiform gyrus would correlate with acquisition of social stimulus value. We tested this using a reinforcement learning algorithm, Q-learning, that assigned values to faces as a function of a history of pairing, or not pairing, with aversive shocks. Behaviourally, we observed a correlation between conditioning induced changes in skin conductance response (SCR) and subjective ratings for likeability of faces. Activity in both amygdala and fusiform gyrus (FG) correlated with the output of the reinforcement learning algorithm parameterized by these ratings. In amygdala, this effect was greater for averted than direct gaze faces. Furthermore, learning-related activity change in these regions correlated with SCR and subjective ratings. We conclude that amygdala and fusiform encode affective value in a manner that closely approximates a standard computational solution to learning.
Social Cognitive and Affective Neuroscience, in press
To monitor the environment for social threat humans must build affective evaluations of others. These evaluations are malleable and to a high degree shaped by responses engendered by specific social encounters. The precise neuronal mechanism by which these evaluations are constructed is poorly understood. We tested a hypothesis that conjoint activity in amygdala and fusiform gyrus would correlate with acquisition of social stimulus value. We tested this using a reinforcement learning algorithm, Q-learning, that assigned values to faces as a function of a history of pairing, or not pairing, with aversive shocks. Behaviourally, we observed a correlation between conditioning induced changes in skin conductance response (SCR) and subjective ratings for likeability of faces. Activity in both amygdala and fusiform gyrus (FG) correlated with the output of the reinforcement learning algorithm parameterized by these ratings. In amygdala, this effect was greater for averted than direct gaze faces. Furthermore, learning-related activity change in these regions correlated with SCR and subjective ratings. We conclude that amygdala and fusiform encode affective value in a manner that closely approximates a standard computational solution to learning.
ARTICLE UPDATE - Electrophysiological correlates of spatial orienting towards angry faces: A source localization study
Diane L. Santesso, Alicia E. Meuret, Stefan G. Hofmann, Erik M. Mueller, Kyle G. Ratner, Etienne B. Roesch and Diego A. Pizzagalli
Neuropsychologia, in press
The goal of this study was to examine behavioral and electrophysiological correlates of involuntary orienting toward rapidly presented angry faces in non-anxious, healthy adults using a dot-probe task in conjunction with high-density event-related potentials and a distributed source localization technique. Consistent with previous studies, participants showed hypervigilance toward angry faces, as indexed by facilitated response time for validly cued probes following angry faces and an enhanced P1 component. An opposite pattern was found for happy faces suggesting that attention was directed toward the relatively more threatening stimuli within the visual field (neutral faces). Source localization of the P1 effect for angry faces indicated increased activity within the anterior cingulate cortex, possibly reflecting conflict experienced during invalidly cued trials. No modulation of the early C1 component was found for affect or spatial attention. Furthermore, the face-sensitive N170 was not modulated by emotional expression. Results suggest that the earliest modulation of spatial attention by face stimuli is manifested in the P1 component, and provide insights about mechanisms underlying attentional orienting toward cues of threat and social disapproval.
Neuropsychologia, in press
The goal of this study was to examine behavioral and electrophysiological correlates of involuntary orienting toward rapidly presented angry faces in non-anxious, healthy adults using a dot-probe task in conjunction with high-density event-related potentials and a distributed source localization technique. Consistent with previous studies, participants showed hypervigilance toward angry faces, as indexed by facilitated response time for validly cued probes following angry faces and an enhanced P1 component. An opposite pattern was found for happy faces suggesting that attention was directed toward the relatively more threatening stimuli within the visual field (neutral faces). Source localization of the P1 effect for angry faces indicated increased activity within the anterior cingulate cortex, possibly reflecting conflict experienced during invalidly cued trials. No modulation of the early C1 component was found for affect or spatial attention. Furthermore, the face-sensitive N170 was not modulated by emotional expression. Results suggest that the earliest modulation of spatial attention by face stimuli is manifested in the P1 component, and provide insights about mechanisms underlying attentional orienting toward cues of threat and social disapproval.
Tuesday, February 05, 2008
ARTICLE UPDATE - Does it look painful or disgusting? Ask your parietal and cingulate cortex.
Benuzzi F, Lui F, Duzzi D, Nichelli PF, Porro CA.
The Journal of Neuroscience, 28, 923-931
Looking at still images of body parts in situations that are likely to cause pain has been shown to be associated with activation in some brain areas involved in pain processing. Because pain involves both sensory components and negative affect, it is of interest to explore whether the visually evoked representations of pain and of other negative emotions overlap. By means of event-related functional magnetic resonance imaging, here we compare the brain areas recruited, in female volunteers, by the observation of painful, disgusting, or neutral stimuli delivered to one hand or foot. Several cortical foci were activated by the observation of both painful and disgusting video clips, including portions of the medial prefrontal cortex, anterior, mid-, and posterior cingulate cortex, left posterior insula, and right parietal operculum. Signal changes in perigenual cingulate and left anterior insula were linearly related to the perceived unpleasantness, when the individual differences in susceptibility to aversive stimuli were taken into account. Painful scenes selectively induced activation of left parietal foci, including the parietal operculum, the postcentral gyrus, and adjacent portions of the posterior parietal cortex. In contrast, brain foci specific for disgusting scenes were found in the posterior cingulate cortex. These data show both similarities and differences between the brain patterns of activity related to the observation of noxious or disgusting stimuli. Namely, the parietal cortex appears to be particularly involved in the recognition of noxious environmental stimuli, suggesting that areas involved in sensory aspects of pain are specifically triggered by observing noxious events.
The Journal of Neuroscience, 28, 923-931
Looking at still images of body parts in situations that are likely to cause pain has been shown to be associated with activation in some brain areas involved in pain processing. Because pain involves both sensory components and negative affect, it is of interest to explore whether the visually evoked representations of pain and of other negative emotions overlap. By means of event-related functional magnetic resonance imaging, here we compare the brain areas recruited, in female volunteers, by the observation of painful, disgusting, or neutral stimuli delivered to one hand or foot. Several cortical foci were activated by the observation of both painful and disgusting video clips, including portions of the medial prefrontal cortex, anterior, mid-, and posterior cingulate cortex, left posterior insula, and right parietal operculum. Signal changes in perigenual cingulate and left anterior insula were linearly related to the perceived unpleasantness, when the individual differences in susceptibility to aversive stimuli were taken into account. Painful scenes selectively induced activation of left parietal foci, including the parietal operculum, the postcentral gyrus, and adjacent portions of the posterior parietal cortex. In contrast, brain foci specific for disgusting scenes were found in the posterior cingulate cortex. These data show both similarities and differences between the brain patterns of activity related to the observation of noxious or disgusting stimuli. Namely, the parietal cortex appears to be particularly involved in the recognition of noxious environmental stimuli, suggesting that areas involved in sensory aspects of pain are specifically triggered by observing noxious events.
ARTICLE UPDATE - The cognitive consequences of emotion regulation: An ERP investigation.
Deveney CM, Pizzagalli DA.
Psychophysiology, in press
Increasing evidence suggests that emotion regulation (ER) strategies modulate encoding of information presented during regulation; however, no studies have assessed the impact of cognitive reappraisal ER strategies on the processing of stimuli presented after the ER period. Participants in the present study regulated emotions to unpleasant pictures and then judged whether a word was negative or neutral. Electromyographic measures (corrugator supercilli) confirmed that individuals increased and decreased negative affect according to ER condition. Event-related potential analyses revealed smallest N400 amplitudes to negative and neutral words presented after decreasing unpleasant emotions and smallest P300 amplitudes to words presented after increasing unpleasant emotions whereas reaction time data failed to show ER modulations. Results are discussed in the context of the developing ER literature, as well as theories of emotional incongruity (N400) and resource allocation (P300).
Psychophysiology, in press
Increasing evidence suggests that emotion regulation (ER) strategies modulate encoding of information presented during regulation; however, no studies have assessed the impact of cognitive reappraisal ER strategies on the processing of stimuli presented after the ER period. Participants in the present study regulated emotions to unpleasant pictures and then judged whether a word was negative or neutral. Electromyographic measures (corrugator supercilli) confirmed that individuals increased and decreased negative affect according to ER condition. Event-related potential analyses revealed smallest N400 amplitudes to negative and neutral words presented after decreasing unpleasant emotions and smallest P300 amplitudes to words presented after increasing unpleasant emotions whereas reaction time data failed to show ER modulations. Results are discussed in the context of the developing ER literature, as well as theories of emotional incongruity (N400) and resource allocation (P300).
ARTICLE UPDATE - Fearful faces selectively increase corticospinal motor tract excitability: A transcranial magnetic stimulation study.
Schutter DJ, Hofman D, Van Honk J.
Psychophysiology, in press
Fearful facial expressions are danger signals that rapidly trigger a cascade of neurobiological processes defensibly associated with action preparation. However, direct evidence for the activating effects of fearful facial expressions on the motor system is absent. The current transcranial magnetic stimulation (TMS) study investigated whether fearful facial expressions selectively increase corticospinal motor tract (CST) excitability. Focal TMS was applied over the left primary motor cortex during the exposure of fearful, happy, and neutral facial expressions in 12 healthy right-handed volunteers. Changes in CST excitability using the motor evoked potential (MEP) were recorded. Results showed significant selective increases in MEP to fearful facial expressions. These findings provide the first direct evidence for selective increases in CST excitability to threat and contribute to evolutionary views on emotion and action preparedness.
Psychophysiology, in press
Fearful facial expressions are danger signals that rapidly trigger a cascade of neurobiological processes defensibly associated with action preparation. However, direct evidence for the activating effects of fearful facial expressions on the motor system is absent. The current transcranial magnetic stimulation (TMS) study investigated whether fearful facial expressions selectively increase corticospinal motor tract (CST) excitability. Focal TMS was applied over the left primary motor cortex during the exposure of fearful, happy, and neutral facial expressions in 12 healthy right-handed volunteers. Changes in CST excitability using the motor evoked potential (MEP) were recorded. Results showed significant selective increases in MEP to fearful facial expressions. These findings provide the first direct evidence for selective increases in CST excitability to threat and contribute to evolutionary views on emotion and action preparedness.
Tuesday, January 29, 2008
ARTICLE UPDATE - Affective learning modulates spatial competition during low-load attentional conditions.
Lim SL, Padmala S, Pessoa L.
Neuropsychologia, in press
It has been hypothesized that the amygdala mediates the processing advantage of emotional items. In the present study, we employed functional magnetic resonance imaging (fMRI) to investigate how fear conditioning affected the visual processing of task-irrelevant faces. We hypothesized that faces previously paired with shock (threat faces) would more effectively vie for processing resources during conditions involving spatial competition. To investigate this question, following conditioning, participants performed a letter-detection task on an array of letters that was superimposed on task-irrelevant faces. Attentional resources were manipulated by having participants perform an easy or a difficult search task. Our findings revealed that threat fearful faces evoked stronger responses in the amygdala and fusiform gyrus relative to safe fearful faces during low-load attentional conditions, but not during high-load conditions. Consistent with the increased processing of shock-paired stimuli during the low-load condition, such stimuli exhibited increased behavioral priming and fMRI repetition effects relative to unpaired faces during a subsequent implicit-memory task. Overall, our results suggest a competition model in which affective significance signals from the amygdala may constitute a key modulatory factor determining the neural fate of visual stimuli. In addition, it appears that such competitive advantage is only evident when sufficient processing resources are available to process the affective stimulus.
Neuropsychologia, in press
It has been hypothesized that the amygdala mediates the processing advantage of emotional items. In the present study, we employed functional magnetic resonance imaging (fMRI) to investigate how fear conditioning affected the visual processing of task-irrelevant faces. We hypothesized that faces previously paired with shock (threat faces) would more effectively vie for processing resources during conditions involving spatial competition. To investigate this question, following conditioning, participants performed a letter-detection task on an array of letters that was superimposed on task-irrelevant faces. Attentional resources were manipulated by having participants perform an easy or a difficult search task. Our findings revealed that threat fearful faces evoked stronger responses in the amygdala and fusiform gyrus relative to safe fearful faces during low-load attentional conditions, but not during high-load conditions. Consistent with the increased processing of shock-paired stimuli during the low-load condition, such stimuli exhibited increased behavioral priming and fMRI repetition effects relative to unpaired faces during a subsequent implicit-memory task. Overall, our results suggest a competition model in which affective significance signals from the amygdala may constitute a key modulatory factor determining the neural fate of visual stimuli. In addition, it appears that such competitive advantage is only evident when sufficient processing resources are available to process the affective stimulus.
ARTICLE UPDATE - The neural correlates of the affective response to unreciprocated cooperation.
Rilling JK, Goldsmith DR, Glenn AL, Jairam MR, Elfenbein HA, Dagenais JE, Murdock CD, Pagnoni G.
Neuropsychologia, in press
Humans excel at reciprocal altruism in which two individuals exchange altruistic acts to their mutual advantage. The evolutionary stability of this system depends on recognition of and discrimination against non-reciprocators, and the human mind is apparently specialized for detecting non-reciprocators. Here we investigate the neural response to non-reciprocation of cooperation by imaging human subjects with fMRI as they play an iterated Prisoner's dilemma game with two assumed human partners. Unreciprocated cooperation was associated with greater activity in bilateral anterior insula, left hippocampus and left lingual gyrus, compared with reciprocated cooperation. These areas were also more responsive to unreciprocated cooperation than to unsuccessful risk taking in a non-social context. Finally, functional connectivity between anterior insula and lateral orbitofrontal cortex (OFC) in response to unreciprocated cooperation predicted subsequent defection. The anterior insula is involved in awareness of visceral, autonomic feedback from the body and, in concert with the lateral orbitofrontal cortex, may be responsible for negative feeling states that bias subsequent social decision making against cooperation with a non-reciprocating partner.
Neuropsychologia, in press
Humans excel at reciprocal altruism in which two individuals exchange altruistic acts to their mutual advantage. The evolutionary stability of this system depends on recognition of and discrimination against non-reciprocators, and the human mind is apparently specialized for detecting non-reciprocators. Here we investigate the neural response to non-reciprocation of cooperation by imaging human subjects with fMRI as they play an iterated Prisoner's dilemma game with two assumed human partners. Unreciprocated cooperation was associated with greater activity in bilateral anterior insula, left hippocampus and left lingual gyrus, compared with reciprocated cooperation. These areas were also more responsive to unreciprocated cooperation than to unsuccessful risk taking in a non-social context. Finally, functional connectivity between anterior insula and lateral orbitofrontal cortex (OFC) in response to unreciprocated cooperation predicted subsequent defection. The anterior insula is involved in awareness of visceral, autonomic feedback from the body and, in concert with the lateral orbitofrontal cortex, may be responsible for negative feeling states that bias subsequent social decision making against cooperation with a non-reciprocating partner.
ARTICLE UPDATE - On the relationship between emotion and cognition.
Pessoa, L.
Nature Reviews Neuroscience, 9, 148-158
The current view of brain organization supports the notion that there is a considerable degree of functional specialization and that many regions can be conceptualized as either 'affective' or 'cognitive'. Popular examples are the amygdala in the domain of emotion and the lateral prefrontal cortex in the case of cognition. This prevalent view is problematic for a number of reasons. Here, I will argue that complex cognitive-emotional behaviours have their basis in dynamic coalitions of networks of brain areas, none of which should be conceptualized as specifically affective or cognitive. Central to cognitive-emotional interactions are brain areas with a high degree of connectivity, called hubs, which are critical for regulating the flow and integration of information between regions.
Nature Reviews Neuroscience, 9, 148-158
The current view of brain organization supports the notion that there is a considerable degree of functional specialization and that many regions can be conceptualized as either 'affective' or 'cognitive'. Popular examples are the amygdala in the domain of emotion and the lateral prefrontal cortex in the case of cognition. This prevalent view is problematic for a number of reasons. Here, I will argue that complex cognitive-emotional behaviours have their basis in dynamic coalitions of networks of brain areas, none of which should be conceptualized as specifically affective or cognitive. Central to cognitive-emotional interactions are brain areas with a high degree of connectivity, called hubs, which are critical for regulating the flow and integration of information between regions.
ARTICLE UPDATE - Emotional influences on spatial attention.
Foster PS, Drago V, Webster DG, Harrison DW, Crucian GP, Heilman KM.
Neuropsychology, 22, 127-135
The relationships between the anterior-posterior and left-right regions of the brain have been characterized as mutually inhibitory. Whereas the left hemisphere attends to right proximal hemispace and is associated with positive emotions, the right hemisphere attends to left distal hemispace and is associated with negative emotions. Because of the excitatory and inhibitory influences between the left and right frontal and posterior regions of the brain, the expression of emotion will result in an ipsilateral attentional bias. Given these functional systems, we hypothesized that positive emotions would be associated with a bias for left distal hemispace and negative emotions would be associated with a bias for right proximal hemispace. We tested these hypotheses by having 138 undergraduate students place emotionally labeled pegs on a large board. Our results indicated that the positively labeled pegs were placed in left distal hemispace and the relative placement of negatively labeled pegs was rightward and proximally. Whereas numerous research investigations have examined how attention is biased for emotional stimuli, ours is the first investigation to provide evidence that emotions can bias attentional allocation.
Neuropsychology, 22, 127-135
The relationships between the anterior-posterior and left-right regions of the brain have been characterized as mutually inhibitory. Whereas the left hemisphere attends to right proximal hemispace and is associated with positive emotions, the right hemisphere attends to left distal hemispace and is associated with negative emotions. Because of the excitatory and inhibitory influences between the left and right frontal and posterior regions of the brain, the expression of emotion will result in an ipsilateral attentional bias. Given these functional systems, we hypothesized that positive emotions would be associated with a bias for left distal hemispace and negative emotions would be associated with a bias for right proximal hemispace. We tested these hypotheses by having 138 undergraduate students place emotionally labeled pegs on a large board. Our results indicated that the positively labeled pegs were placed in left distal hemispace and the relative placement of negatively labeled pegs was rightward and proximally. Whereas numerous research investigations have examined how attention is biased for emotional stimuli, ours is the first investigation to provide evidence that emotions can bias attentional allocation.
ARTICLE UPDATE - Deconstructing Reappraisal: Descriptions Preceding Arousing Pictures Modulate the Subsequent Neural Response.
Foti D, Hajcak G.
Journal of Cognitive Neuroscience, in press
Abstract The late positive potential (LPP) is a sustained positive deflection in the event-related potential that is larger following the presentation of emotional compared to neutral visual stimuli. Recent studies have indicated that the magnitude of the LPP is sensitive to emotion regulation strategies such as reappraisal, which involves generating an alternate interpretation of emotional stimuli so that they are less negative. It is unclear, however, whether reappraisal-related reductions in the LPP reflect reduced emotional processing or increased cognitive demands following reappraisal instructions. In the present study, we sought to examine whether a more or less negative description preceding the presentation of unpleasant images would similarly modulate the LPP. The LPP was recorded from 26 subjects as they viewed unpleasant and neutral International Affective Picture System images. All participants heard a brief description of the upcoming picture; prior to unpleasant images, this description was either more neutral or more negative. Following the more neutral description, the magnitude of the LPP, unpleasant ratings, and arousal ratings were all reliably reduced. These results indicate that changes in narrative are sufficient to modulate the electrocortical response to the initial viewing of emotional pictures, and are discussed in terms of recent studies on reappraisal and emotion regulation.
Journal of Cognitive Neuroscience, in press
Abstract The late positive potential (LPP) is a sustained positive deflection in the event-related potential that is larger following the presentation of emotional compared to neutral visual stimuli. Recent studies have indicated that the magnitude of the LPP is sensitive to emotion regulation strategies such as reappraisal, which involves generating an alternate interpretation of emotional stimuli so that they are less negative. It is unclear, however, whether reappraisal-related reductions in the LPP reflect reduced emotional processing or increased cognitive demands following reappraisal instructions. In the present study, we sought to examine whether a more or less negative description preceding the presentation of unpleasant images would similarly modulate the LPP. The LPP was recorded from 26 subjects as they viewed unpleasant and neutral International Affective Picture System images. All participants heard a brief description of the upcoming picture; prior to unpleasant images, this description was either more neutral or more negative. Following the more neutral description, the magnitude of the LPP, unpleasant ratings, and arousal ratings were all reliably reduced. These results indicate that changes in narrative are sufficient to modulate the electrocortical response to the initial viewing of emotional pictures, and are discussed in terms of recent studies on reappraisal and emotion regulation.
Tuesday, January 22, 2008
ARTICLE UPDATE - Regions of the MPFC differentially tuned to social and nonsocial affective evaluation.
Harris LT, McClure SM, van den Bos W, Cohen JD, Fiske ST.
Cognitive, Affective and Behavioral Neuroscience, 7, 309-316.
The medial prefrontal cortex (MPFC) reliably activates in social cognition and reward tasks. This study locates distinct areas for each. Participants made evaluative (positive/negative) or social (person/not a person) judgments of pictured positive or negative people and objects in a slow event-related design. Activity in an anterior rostral region (arMPFC) was significantly greater for positive than for negative persons but did not show a valence effect for objects, and this was true regardless of the judgment task. This suggests that the arMPFC is tuned to social valence. Interestingly, however, no regions of the MPFC were found to be responsive to social information independently of valence. A region-of-interest analysis of the para-anterior cingulate cortex (pACC), previously implicated in reward processing, demonstrated sensitivity to the valence of all stimuli, whether persons or objects, across tasks. Affective evaluation may be a general function of the MPFC, with some regions being tuned to more specific domains of information (e.g., social) than are others.
Cognitive, Affective and Behavioral Neuroscience, 7, 309-316.
The medial prefrontal cortex (MPFC) reliably activates in social cognition and reward tasks. This study locates distinct areas for each. Participants made evaluative (positive/negative) or social (person/not a person) judgments of pictured positive or negative people and objects in a slow event-related design. Activity in an anterior rostral region (arMPFC) was significantly greater for positive than for negative persons but did not show a valence effect for objects, and this was true regardless of the judgment task. This suggests that the arMPFC is tuned to social valence. Interestingly, however, no regions of the MPFC were found to be responsive to social information independently of valence. A region-of-interest analysis of the para-anterior cingulate cortex (pACC), previously implicated in reward processing, demonstrated sensitivity to the valence of all stimuli, whether persons or objects, across tasks. Affective evaluation may be a general function of the MPFC, with some regions being tuned to more specific domains of information (e.g., social) than are others.
ARTICLE UPDATE - Dissociating affective evaluation and social cognitive processes in the ventral medial prefrontal cortex.
van den Bos W, McClure SM, Harris LT, Fiske ST, Cohen JD.
Cognitive, Affective and Behavioural Neuroscience, 7, 337-346
In recent studies, various regions of the ventral medial prefrontal cortex (vmPFC) have been implicated in at least two potentially different mental functions: reasoning about the minds of other people (social cognition) and processing reward related information (affective evaluation). In this study, we test whether the activation in a specific area of the vmPFC, the para-anterior cingulate cortex (PACC), correlates with the reward value of stimuli in general or is specifically associated with social cognition. Participants performed a time estimation task with trial-to-trial feedback in which reward and socialcontext were manipulated separately. Reward was manipulated by giving either positive or negative feedback in the form of small squirts of fluid delivered orally. Social context was manipulated by instructing participants that positive and negative feedback was determined by another person or a computer. The data demonstrate a main effect of feedback, but not social context, in the PACC, suggesting that this area of the vmPFC serves a general function in evaluating and/or representing reward value. In addition, activity in a more anterior subregion of the vmPFC demonstrated reward-related sensitivity only in the social context. Another area that showed a similar interaction was the subgenual cingulate, but this region was only sensitive to negative feedback in the social condition. These findings suggest that, within the vmPFC, the PACC subserves primarily an affective function, whereas in other regions social context can modulate affective responses.
Cognitive, Affective and Behavioural Neuroscience, 7, 337-346
In recent studies, various regions of the ventral medial prefrontal cortex (vmPFC) have been implicated in at least two potentially different mental functions: reasoning about the minds of other people (social cognition) and processing reward related information (affective evaluation). In this study, we test whether the activation in a specific area of the vmPFC, the para-anterior cingulate cortex (PACC), correlates with the reward value of stimuli in general or is specifically associated with social cognition. Participants performed a time estimation task with trial-to-trial feedback in which reward and socialcontext were manipulated separately. Reward was manipulated by giving either positive or negative feedback in the form of small squirts of fluid delivered orally. Social context was manipulated by instructing participants that positive and negative feedback was determined by another person or a computer. The data demonstrate a main effect of feedback, but not social context, in the PACC, suggesting that this area of the vmPFC serves a general function in evaluating and/or representing reward value. In addition, activity in a more anterior subregion of the vmPFC demonstrated reward-related sensitivity only in the social context. Another area that showed a similar interaction was the subgenual cingulate, but this region was only sensitive to negative feedback in the social condition. These findings suggest that, within the vmPFC, the PACC subserves primarily an affective function, whereas in other regions social context can modulate affective responses.
ARTICLE UPDATE - Neural circuitry for accurate identification of facial emotions.
Loughead J, Gur RC, Elliott M, Gur RE.
Brain Research, in press
Converging studies have revealed neural circuits for emotion processing, yet none has related activation to identification accuracy. We report a hybrid (block and event-related) fMRI study in 17 healthy adults, which permitted performance-based analysis. As in earlier studies, blocked analysis of the facial emotion identification task showed activation of amygdala, fusiform, thalamus, inferior and midfrontal regions. However, an event-related analysis of target stimuli demonstrated time locked activation associated with correct identification of happy, sad, angry and fearful faces. Overall, correct detection of angry and fearful faces was associated with greater activation compared to incorrect responses, especially in the amygdala and fusiform gyrus. The opposite was observed for happy and sad faces, where greater thalamic and midfrontal activation portended incorrect responses. Results indicate that the fusiform cortex and amygdala respond differentially in the four target conditions (happy, sad, angry and fearful) along the dimension of threat-relatedness.
Brain Research, in press
Converging studies have revealed neural circuits for emotion processing, yet none has related activation to identification accuracy. We report a hybrid (block and event-related) fMRI study in 17 healthy adults, which permitted performance-based analysis. As in earlier studies, blocked analysis of the facial emotion identification task showed activation of amygdala, fusiform, thalamus, inferior and midfrontal regions. However, an event-related analysis of target stimuli demonstrated time locked activation associated with correct identification of happy, sad, angry and fearful faces. Overall, correct detection of angry and fearful faces was associated with greater activation compared to incorrect responses, especially in the amygdala and fusiform gyrus. The opposite was observed for happy and sad faces, where greater thalamic and midfrontal activation portended incorrect responses. Results indicate that the fusiform cortex and amygdala respond differentially in the four target conditions (happy, sad, angry and fearful) along the dimension of threat-relatedness.
Monday, January 14, 2008
ARTICLE UPDATE - Re-entrant projections modulate visual cortex in affective perception: Evidence from Granger causality analysis.
Keil A, Sabatinelli D, Ding M, Lang PJ, Ihssen N, Heim S.
Human Brain Mapping, in press
Re-entrant modulation of visual cortex has been suggested as a critical process for enhancing perception of emotionally arousing visual stimuli. This study explores how the time information inherent in large-scale electrocortical measures can be used to examine the functional relationships among the structures involved in emotional perception. Granger causality analysis was conducted on steady-state visual evoked potentials elicited by emotionally arousing pictures flickering at a rate of 10 Hz. This procedure allows one to examine the direction of neural connections. Participants viewed pictures that varied in emotional content, depicting people in neutral contexts, erotica, or interpersonal attack scenes. Results demonstrated increased coupling between visual and cortical areas when viewing emotionally arousing content. Specifically, intraparietal to inferotemporal and precuneus to calcarine connections were stronger for emotionally arousing picture content. Thus, we provide evidence for re-entrant signal flow during emotional perception, which originates from higher tiers and enters lower tiers of visual cortex.
Human Brain Mapping, in press
Re-entrant modulation of visual cortex has been suggested as a critical process for enhancing perception of emotionally arousing visual stimuli. This study explores how the time information inherent in large-scale electrocortical measures can be used to examine the functional relationships among the structures involved in emotional perception. Granger causality analysis was conducted on steady-state visual evoked potentials elicited by emotionally arousing pictures flickering at a rate of 10 Hz. This procedure allows one to examine the direction of neural connections. Participants viewed pictures that varied in emotional content, depicting people in neutral contexts, erotica, or interpersonal attack scenes. Results demonstrated increased coupling between visual and cortical areas when viewing emotionally arousing content. Specifically, intraparietal to inferotemporal and precuneus to calcarine connections were stronger for emotionally arousing picture content. Thus, we provide evidence for re-entrant signal flow during emotional perception, which originates from higher tiers and enters lower tiers of visual cortex.
ARTICLE UPDATE - Affective visual event-related potentials: Arousal, valence, and repetition effects for normal and distorted pictures.
Rozenkrants B, Olofsson JK, Polich J.
International Journal of Psychophysiology, in press
Event-related potentials (ERPs) were used to assess arousal (low, high), valence (negative, positive), and stimulus repetition effects for normal and distorted images from the International Affective Pictures System (IAPS). Distorted stimuli were constructed by dividing each image into small squares and rearranging the segments randomly to produce a “scrambled” picture. Event-related potentials (ERPs) were elicited by presenting the normal and scrambled images as target stimuli, with a repeated visual pattern used as the standard stimulus. Participants (N = 32) were instructed to press a button to the targets and ignore the standard. Stimulus repetition effects were assessed by presenting each stimulus twice in the normal and scrambled condition. High-arousal stimuli yielded larger late positive components for both the normal and scrambled pictures. No overall valence effects were obtained, but arousal and valence influenced component amplitudes for middle-latency ERPs from the scrambled stimuli. For the normal pictures, stimulus repetition was associated with increased component amplitudes for all potentials and decreased RTs of all affective categories. For the scrambled pictures, no repetition changes were obtained. The findings suggest that stimulus arousal level contributes more than valence to affective ERP measures for normal as well as perceptually distorted pictures. Stimulus repetition engages memory for previous normal picture items but is not influenced by affective category. Theoretical implications are discussed.
International Journal of Psychophysiology, in press
Event-related potentials (ERPs) were used to assess arousal (low, high), valence (negative, positive), and stimulus repetition effects for normal and distorted images from the International Affective Pictures System (IAPS). Distorted stimuli were constructed by dividing each image into small squares and rearranging the segments randomly to produce a “scrambled” picture. Event-related potentials (ERPs) were elicited by presenting the normal and scrambled images as target stimuli, with a repeated visual pattern used as the standard stimulus. Participants (N = 32) were instructed to press a button to the targets and ignore the standard. Stimulus repetition effects were assessed by presenting each stimulus twice in the normal and scrambled condition. High-arousal stimuli yielded larger late positive components for both the normal and scrambled pictures. No overall valence effects were obtained, but arousal and valence influenced component amplitudes for middle-latency ERPs from the scrambled stimuli. For the normal pictures, stimulus repetition was associated with increased component amplitudes for all potentials and decreased RTs of all affective categories. For the scrambled pictures, no repetition changes were obtained. The findings suggest that stimulus arousal level contributes more than valence to affective ERP measures for normal as well as perceptually distorted pictures. Stimulus repetition engages memory for previous normal picture items but is not influenced by affective category. Theoretical implications are discussed.
ARTICLE UPDATE - Affective picture processing: An integrative review of ERP findings.
Olofsson JK, Nordin S, Sequeira H, Polich J.
Biological Psychology, in press
The review summarizes and integrates findings from 40 years of event-related potential (ERP) studies using pictures that differ in valence (unpleasant-to-pleasant) and arousal (low-to-high) and that are used to elicit emotional processing. Affective stimulus factors primarily modulate ERP component amplitude, with little change in peak latency observed. Arousal effects are consistently obtained, and generally occur at longer latencies. Valence effects are inconsistently reported at several latency ranges, including very early components. Some affective ERP modulations vary with recording methodology, stimulus factors, as well as task-relevance and emotional state. Affective ERPs have been linked theoretically to attention orientation for unpleasant pictures at earlier components (<300 ms). Enhanced stimulus processing has been associated with memory encoding for arousing pictures of assumed intrinsic motivational relevance, with task-induced differences contributing to emotional reactivity at later components (>300 ms). Theoretical issues, stimulus factors, task demands, and individual differences are discussed.
Biological Psychology, in press
The review summarizes and integrates findings from 40 years of event-related potential (ERP) studies using pictures that differ in valence (unpleasant-to-pleasant) and arousal (low-to-high) and that are used to elicit emotional processing. Affective stimulus factors primarily modulate ERP component amplitude, with little change in peak latency observed. Arousal effects are consistently obtained, and generally occur at longer latencies. Valence effects are inconsistently reported at several latency ranges, including very early components. Some affective ERP modulations vary with recording methodology, stimulus factors, as well as task-relevance and emotional state. Affective ERPs have been linked theoretically to attention orientation for unpleasant pictures at earlier components (<300 ms). Enhanced stimulus processing has been associated with memory encoding for arousing pictures of assumed intrinsic motivational relevance, with task-induced differences contributing to emotional reactivity at later components (>300 ms). Theoretical issues, stimulus factors, task demands, and individual differences are discussed.
ARTICLE UPDATE - Affective blindsight in the intact brain: Neural interhemispheric summation for unseen fearful expressions.
Tamietto M, de Gelder B.
Neuropsychologia, in press
The emotional valence of facial expressions can be reliably discriminated even in the absence of conscious visual experience by patients with lesions to the primary visual cortex (affective blindsight). Prior studies in one such patient (GY) also showed that this non-conscious perception can influence conscious recognition of normally seen emotional faces. Here we report a similar online interaction across hemispheres between conscious and non-conscious perception of emotions in normal observers. Fearful and happy facial expressions were presented either unilaterally (to the left or right visual field) or simultaneously to both visual fields. In bilateral displays, conscious perception of one face in a pair was prevented by backward masking after 20 ms, while the opposite expression remained normally visible. The results showed a bidirectional influence of non-conscious fear processing over conscious recognition of happy as well as fearful expressions. Consciously perceived fearful faces were more readily recognized when they were paired with invisible emotionally congruent fearful expressions in the opposite field, as compared to the single presentation of the same unmasked faces. On the other hand, recognition of unmasked happy faces was delayed by the simultaneous presence of a masked fearful face. No such effect was reported for masked happy expressions. These findings show that non-conscious processing of fear may modulate ongoing conscious evaluation of facial expressions via neural interhemispheric summation even in the intact brain.
Neuropsychologia, in press
The emotional valence of facial expressions can be reliably discriminated even in the absence of conscious visual experience by patients with lesions to the primary visual cortex (affective blindsight). Prior studies in one such patient (GY) also showed that this non-conscious perception can influence conscious recognition of normally seen emotional faces. Here we report a similar online interaction across hemispheres between conscious and non-conscious perception of emotions in normal observers. Fearful and happy facial expressions were presented either unilaterally (to the left or right visual field) or simultaneously to both visual fields. In bilateral displays, conscious perception of one face in a pair was prevented by backward masking after 20 ms, while the opposite expression remained normally visible. The results showed a bidirectional influence of non-conscious fear processing over conscious recognition of happy as well as fearful expressions. Consciously perceived fearful faces were more readily recognized when they were paired with invisible emotionally congruent fearful expressions in the opposite field, as compared to the single presentation of the same unmasked faces. On the other hand, recognition of unmasked happy faces was delayed by the simultaneous presence of a masked fearful face. No such effect was reported for masked happy expressions. These findings show that non-conscious processing of fear may modulate ongoing conscious evaluation of facial expressions via neural interhemispheric summation even in the intact brain.
ARTICLE UPDATE - Dissociating love-related attention from task-related attention: An event-related potential oddball study.
Langeslag SJ, Franken IH, Van Strien JW.
Neuroscience Letters, in press
The present event-related potential (ERP) study was conducted to investigate the P3 component in response to love-related stimuli while controlling for task-related factors, and to dissociate the influences of both love-related and task-related attention on the P3 amplitude. In an oddball paradigm, photographs of beloved and friends served as target and distractor stimuli. Love-related and task-related attention were separated by varying the target and distractor status of the beloved and friends full factorially. As expected, the P3 amplitude was larger for beloved compared to friends and for targets compared to distractors. Moreover, task-related and love-related attention were unconfounded. These results are in line with findings that the P3 is modulated by both emotion- and task-related factors, supporting the view that the P3 amplitude reflects attention. Furthermore, this study validates the notion that romantic love is accompanied by increased attention for stimuli associated with the beloved, and also shows that this form of attention is different from task-related attention.
Neuroscience Letters, in press
The present event-related potential (ERP) study was conducted to investigate the P3 component in response to love-related stimuli while controlling for task-related factors, and to dissociate the influences of both love-related and task-related attention on the P3 amplitude. In an oddball paradigm, photographs of beloved and friends served as target and distractor stimuli. Love-related and task-related attention were separated by varying the target and distractor status of the beloved and friends full factorially. As expected, the P3 amplitude was larger for beloved compared to friends and for targets compared to distractors. Moreover, task-related and love-related attention were unconfounded. These results are in line with findings that the P3 is modulated by both emotion- and task-related factors, supporting the view that the P3 amplitude reflects attention. Furthermore, this study validates the notion that romantic love is accompanied by increased attention for stimuli associated with the beloved, and also shows that this form of attention is different from task-related attention.
ARTICLE UPDATE - An ERP investigation on the temporal dynamics of emotional prosody and emotional semantics in pseudo- and lexical-sentence context.
Paulmann S, Kotz SA.
Brain and Language, in press
Previous evidence supports differential event-related brain potential (ERP) responses for emotional prosodic processing and integrative emotional prosodic/semantic processing. While latter process elicits a negativity similar to the well-known N400 component, transitions in emotional prosodic processing elicit a positivity. To further substantiate this evidence, the current investigation utilized lexical-sentences and sentences without lexical content (pseudo-sentences) spoken in six basic emotions by a female and a male speaker. Results indicate that emotional prosodic expectancy violations elicit a right-lateralized positive-going ERP component independent of basic emotional prosodies and speaker voice. In addition, expectancy violations of integrative emotional prosody/semantics elicit a negativity with a whole-head distribution. The current results nicely complement previous evidence, and extend the results by showing the respective effects for a wider range of emotional prosodies independent of lexical content and speaker voice.
Brain and Language, in press
Previous evidence supports differential event-related brain potential (ERP) responses for emotional prosodic processing and integrative emotional prosodic/semantic processing. While latter process elicits a negativity similar to the well-known N400 component, transitions in emotional prosodic processing elicit a positivity. To further substantiate this evidence, the current investigation utilized lexical-sentences and sentences without lexical content (pseudo-sentences) spoken in six basic emotions by a female and a male speaker. Results indicate that emotional prosodic expectancy violations elicit a right-lateralized positive-going ERP component independent of basic emotional prosodies and speaker voice. In addition, expectancy violations of integrative emotional prosody/semantics elicit a negativity with a whole-head distribution. The current results nicely complement previous evidence, and extend the results by showing the respective effects for a wider range of emotional prosodies independent of lexical content and speaker voice.
ARTICLE UPDATE - The role of social cognition in emotion.
Olsson A, Ochsner KN.
Trends in Cognitive Sciences, in press
Although recent research has shown that social cognition and emotion engage overlapping regions of the brain, few accounts of this overlap have been offered. What systems might be commonly or distinctively involved in each? The close functional relationship between social cognition and emotion might be understood in terms of a central role for mental state attribution in the understanding, learning and regulation of emotion. In each of these cases, mental state attributions might be supported by either stimulus-driven or more reflective processes.
Trends in Cognitive Sciences, in press
Although recent research has shown that social cognition and emotion engage overlapping regions of the brain, few accounts of this overlap have been offered. What systems might be commonly or distinctively involved in each? The close functional relationship between social cognition and emotion might be understood in terms of a central role for mental state attribution in the understanding, learning and regulation of emotion. In each of these cases, mental state attributions might be supported by either stimulus-driven or more reflective processes.
ARTICLE UPDATE - EMOTLAB: software for studying emotional signaling in economic bargaining games.
Ketelaar T, Preston B, Russell D, Davis M, Strosser G.
Behaviour Research Method, 39, 959-972
EMOTLAB software creates a virtual social environment in which individuals interact via computer with a virtual interaction partner in a series of economic bargaining games. The virtual partner appears on the participant's computer screen as a digital image (e.g., video or picture file) during each trial. A key feature of EMOTLAB software is its ability to control both the strategic behavior and the emotion signaling behavior (e.g., anger vs. embarrassment) of the virtual interaction partner. By simply editing a series of text files that control the subroutines governing the different features of the experiment (payoff structure, number of trials, etc.), EMOTLAB can generate an essentially infinite number of different social bargaining situations in which participants earn monetary payoffs contingent upon their decisions. This paper provides an overview of this software and how one can edit various subroutines to generate a typical experimental session in which research participants encounter a virtual interaction partner who displays different emotional signals.
Behaviour Research Method, 39, 959-972
EMOTLAB software creates a virtual social environment in which individuals interact via computer with a virtual interaction partner in a series of economic bargaining games. The virtual partner appears on the participant's computer screen as a digital image (e.g., video or picture file) during each trial. A key feature of EMOTLAB software is its ability to control both the strategic behavior and the emotion signaling behavior (e.g., anger vs. embarrassment) of the virtual interaction partner. By simply editing a series of text files that control the subroutines governing the different features of the experiment (payoff structure, number of trials, etc.), EMOTLAB can generate an essentially infinite number of different social bargaining situations in which participants earn monetary payoffs contingent upon their decisions. This paper provides an overview of this software and how one can edit various subroutines to generate a typical experimental session in which research participants encounter a virtual interaction partner who displays different emotional signals.
ARTICLE UPDATE - Characterization of the affective norms for English words by discrete emotional categories.
Stevenson RA, Mikels JA, James TW.
Brain Research Methods, 39, 1020-1024
The Affective Norms for English Words (ANEW) are a commonly used set of 1034 words characterized on the affective dimensions of valence, arousal, and dominance. Traditionally, studies of affect have used stimuli characterized along either affective dimensions or discrete emotional categories, but much current research draws on both of these perspectives. As such, stimuli that have been thoroughly characterized according to both of these approaches are exceptionally useful. In an effort to provide researchers with such a characterization of stimuli, we have collected descriptive data on the ANEW to identify which discrete emotions are elicited by each word in the set. Our data, coupled with previous characterizations of the dimensional aspects of these words, will allow researchers to control for or manipulate stimulus properties in accordance with both dimensional and discrete emotional views, and provide an avenue for further integration of these two perspectives. Our data have been archived at www.psychonomic.org/archive/.
Brain Research Methods, 39, 1020-1024
The Affective Norms for English Words (ANEW) are a commonly used set of 1034 words characterized on the affective dimensions of valence, arousal, and dominance. Traditionally, studies of affect have used stimuli characterized along either affective dimensions or discrete emotional categories, but much current research draws on both of these perspectives. As such, stimuli that have been thoroughly characterized according to both of these approaches are exceptionally useful. In an effort to provide researchers with such a characterization of stimuli, we have collected descriptive data on the ANEW to identify which discrete emotions are elicited by each word in the set. Our data, coupled with previous characterizations of the dimensional aspects of these words, will allow researchers to control for or manipulate stimulus properties in accordance with both dimensional and discrete emotional views, and provide an avenue for further integration of these two perspectives. Our data have been archived at www.psychonomic.org/archive/.
ARTICLE UPDATE -Visual noise effects on emotion perception: brain potentials and stimulus identification.
Schupp HT, Stockburger J, Schmälzle R, Bublatzky F, Weike AI, Hamm AO.
Neuroreport, 19, 167-171
Event-related potential (ERP) studies revealed an early posterior negativity (EPN) for emotionally arousing pictures. Two studies explored how this effect relates to perceptual stimulus characteristics and stimulus identification. Adding various amounts of visual noise varied stimulus perceptibility of high and low arousing picture contents, which were presented as rapid and continuous stream. Measuring dense sensor event-related potentials, study I determined that noise level was linearly related to the P1 peak. Subsequently, enlarged EPNs to emotionally arousing contents were observed, however, only for pictures containing low amounts of noise, which also enabled stimulus identification as shown by study II. These data support the notion that the EPN may serve as a measure of affective stimulus evaluation at an early transitory processing period.
Neuroreport, 19, 167-171
Event-related potential (ERP) studies revealed an early posterior negativity (EPN) for emotionally arousing pictures. Two studies explored how this effect relates to perceptual stimulus characteristics and stimulus identification. Adding various amounts of visual noise varied stimulus perceptibility of high and low arousing picture contents, which were presented as rapid and continuous stream. Measuring dense sensor event-related potentials, study I determined that noise level was linearly related to the P1 peak. Subsequently, enlarged EPNs to emotionally arousing contents were observed, however, only for pictures containing low amounts of noise, which also enabled stimulus identification as shown by study II. These data support the notion that the EPN may serve as a measure of affective stimulus evaluation at an early transitory processing period.
ARTICLE UPDATE - Early emotional prosody perception based on different speaker voices.
Paulmann S, Kotz SA.
Neuroreport, 19, 209-213
Decoding verbal and nonverbal emotional expressions is an important part of speech communication. Although various studies have tried to specify the brain regions that underlie different emotions conveyed in speech, few studies have aimed to specify the time course of emotional speech decoding. We used event-related potentials to determine when emotional speech is first differentiated from neutral speech. Participants engaged in an implicit emotional processing task (probe verification) while listening to emotional sentences spoken by a female and a male speaker. Independent of speaker voice, emotional sentences could be differentiated from neutral sentences as early as 200 ms after sentence onset (P200), suggesting rapid emotional decoding.
Neuroreport, 19, 209-213
Decoding verbal and nonverbal emotional expressions is an important part of speech communication. Although various studies have tried to specify the brain regions that underlie different emotions conveyed in speech, few studies have aimed to specify the time course of emotional speech decoding. We used event-related potentials to determine when emotional speech is first differentiated from neutral speech. Participants engaged in an implicit emotional processing task (probe verification) while listening to emotional sentences spoken by a female and a male speaker. Independent of speaker voice, emotional sentences could be differentiated from neutral sentences as early as 200 ms after sentence onset (P200), suggesting rapid emotional decoding.
Thursday, December 27, 2007
ARTICLE UPDATE - What Are You Feeling? Using Functional Magnetic Resonance Imaging to Assess the Modulation of Sensory and Affective Responses during
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.
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.
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.
Subscribe to:
Posts (Atom)