Creswell JD, Way BM, Eisenberger NI, Lieberman MD.
Psychosomatic Medicine, 69, 560-565
Objective: Mindfulness is a process whereby one is aware and receptive to present moment experiences. Although mindfulness-enhancing interventions reduce pathological mental and physical health symptoms across a wide variety of conditions and diseases, the mechanisms underlying these effects remain unknown. Converging evidence from the mindfulness and neuroscience literature suggests that labeling affect may be one mechanism for these effects. Methods: Participants (n = 27) indicated trait levels of mindfulness and then completed an affect labeling task while undergoing functional magnetic resonance imaging. The labeling task consisted of matching facial expressions to appropriate affect words (affect labeling) or to gender-appropriate names (gender labeling control task). Results: After controlling for multiple individual difference measures, dispositional mindfulness was associated with greater widespread prefrontal cortical activation, and reduced bilateral amygdala activity during affect labeling, compared with the gender labeling control task. Further, strong negative associations were found between areas of prefrontal cortex and right amygdala responses in participants high in mindfulness but not in participants low in mindfulness. Conclusions: The present findings with a dispositional measure of mindfulness suggest one potential neurocognitive mechanism for understanding how mindfulness meditation interventions reduce negative affect and improve health outcomes, showing that mindfulness is associated with enhanced prefrontal cortical regulation of affect through labeling of negative affective stimuli.
Friday, July 27, 2007
ARTICLE UPDATE - Dissociable prefrontal networks for cognitive and affective theory of mind: A lesion study.
Shamay-Tsoory SG, Aharon-Peretz J.
Neuropsychologia, in press
The underlying mechanisms and neuroanatomical correlates of theory of mind (ToM), the ability to make inferences on others’ mental states, remain largely unknown. While numerous studies have implicated the ventromedial (VM) frontal lobes in ToM, recent findings have questioned the role of the prefrontal cortex. We designed two novel tasks that examined the hypothesis that affective ToM processing is distinct from that related to cognitive ToM and depends in part on separate anatomical substrates.
The performance of patients with localized lesions in the VM was compared to responses of patients with dorsolateral lesions, mixed prefrontal lesions, and posterior lesions and with healthy control subjects. While controls made fewer errors on affective as compared to cognitive ToM conditions in both tasks, patients with VM damage showed a different trend. Furthermore, while affective ToM was mostly impaired by VM damage, cognitive ToM was mostly impaired by extensive prefrontal damage, suggesting that cognitive and affective mentalizing abilities are partly dissociable.
By introducing the concept of ‘affective ToM’ to the study of social cognition, these results offer new insights into the mediating role of the VM in the affective facets of social behavior that may underlie the behavioral disturbances observed in these patients.
Neuropsychologia, in press
The underlying mechanisms and neuroanatomical correlates of theory of mind (ToM), the ability to make inferences on others’ mental states, remain largely unknown. While numerous studies have implicated the ventromedial (VM) frontal lobes in ToM, recent findings have questioned the role of the prefrontal cortex. We designed two novel tasks that examined the hypothesis that affective ToM processing is distinct from that related to cognitive ToM and depends in part on separate anatomical substrates.
The performance of patients with localized lesions in the VM was compared to responses of patients with dorsolateral lesions, mixed prefrontal lesions, and posterior lesions and with healthy control subjects. While controls made fewer errors on affective as compared to cognitive ToM conditions in both tasks, patients with VM damage showed a different trend. Furthermore, while affective ToM was mostly impaired by VM damage, cognitive ToM was mostly impaired by extensive prefrontal damage, suggesting that cognitive and affective mentalizing abilities are partly dissociable.
By introducing the concept of ‘affective ToM’ to the study of social cognition, these results offer new insights into the mediating role of the VM in the affective facets of social behavior that may underlie the behavioral disturbances observed in these patients.
ARTICLE UPDATE - Source monitoring is not always enhanced for valenced material.
Cook GI, Hicks JL, Marsh RL.
Memory & Cognition, 35, 222-230
Source monitoring for valenced materials has received very little attention from researchers interested in the residual effects that emotion can have on memory. The three previous studies that examined memory for valenced material found a source-monitoring enhancement effect. By contrast, we used two different combinations of sources and found a novel, consistent source-monitoring deficit for valenced words as compared with neutral ones. In addition, this memory deficit for contextual details did not consistently covary with item memory. We assert that it is possible to obtain an effect in which heightened attention toward valenced material reduces the binding of contextual details into memory.
Memory & Cognition, 35, 222-230
Source monitoring for valenced materials has received very little attention from researchers interested in the residual effects that emotion can have on memory. The three previous studies that examined memory for valenced material found a source-monitoring enhancement effect. By contrast, we used two different combinations of sources and found a novel, consistent source-monitoring deficit for valenced words as compared with neutral ones. In addition, this memory deficit for contextual details did not consistently covary with item memory. We assert that it is possible to obtain an effect in which heightened attention toward valenced material reduces the binding of contextual details into memory.
Friday, July 20, 2007
ARTICLE UPDATE - Behold the voice of wrath: Cross-modal modulation of visual attention by anger prosody.
Brosch T, Grandjean D, Sander D, Scherer KR.
Cognition, in press
Emotionally relevant stimuli are prioritized in human information processing. It has repeatedly been shown that selective spatial attention is modulated by the emotional content of a stimulus. Until now, studies investigating this phenomenon have only examined within-modality effects, most frequently using pictures of emotional stimuli to modulate visual attention. In this study, we used simultaneously presented utterances with emotional and neutral prosody as cues for a visually presented target in a cross-modal dot probe task. Response times towards targets were faster when they appeared at the location of the source of the emotional prosody. Our results show for the first time a cross-modal attentional modulation of visual attention by auditory affective prosody.
Cognition, in press
Emotionally relevant stimuli are prioritized in human information processing. It has repeatedly been shown that selective spatial attention is modulated by the emotional content of a stimulus. Until now, studies investigating this phenomenon have only examined within-modality effects, most frequently using pictures of emotional stimuli to modulate visual attention. In this study, we used simultaneously presented utterances with emotional and neutral prosody as cues for a visually presented target in a cross-modal dot probe task. Response times towards targets were faster when they appeared at the location of the source of the emotional prosody. Our results show for the first time a cross-modal attentional modulation of visual attention by auditory affective prosody.
ARTICLE UPDATE - Working memory involved in predicting future outcomes based on past experiences
Dretsch MN, Tipples J.
Brain and Cognition, in press
Deficits in working memory have been shown to contribute to poor performance on the Iowa Gambling Task [IGT: Bechara, A., & Martin, E.M. (2004). Impaired decision making related to working memory deficits in individuals with substance addictions. Neuropsychology, 18, 152–162]. Similarly, a secondary memory load task has been shown to impair task performance [Hinson, J., Jameson, T. & Whitney, P. (2002). Somatic markers, working memory, and decision making. Cognitive, Affective, & Behavioural Neuroscience, 2, 341–353]. In the present study, we investigate whether the latter findings were due to increased random responding [Franco-Watkins, A. M., Pashler, H., & Rickard, T. C. (2006). Does working memory load lead to greater impulsivity? Commentary on Hinson, Jameson, and Whitney’s (2003). Journal of Experimental Psychology: Learning, Memory & Cognition, 32, 443–447]. Participants were tested under Low Working Memory (LWM; n = 18) or High Working Memory (HWM; n = 17) conditions while performing the Reversed IGT in which punishment was immediate and reward delayed [Bechara, A., Dolan, S., & Hindes, A. (2002). Decision making and addiction (part II): Myopia for the future or hypersensitivity to reward? Neuropsychologia, 40, 1690–1705]. In support of a role for working memory in emotional decision making, compared to the LWM condition, participants in the HWM condition made significantly greater number of disadvantageous selections than that predicted by chance. Performance by the HWM group could not be fully explained by random responding.
Brain and Cognition, in press
Deficits in working memory have been shown to contribute to poor performance on the Iowa Gambling Task [IGT: Bechara, A., & Martin, E.M. (2004). Impaired decision making related to working memory deficits in individuals with substance addictions. Neuropsychology, 18, 152–162]. Similarly, a secondary memory load task has been shown to impair task performance [Hinson, J., Jameson, T. & Whitney, P. (2002). Somatic markers, working memory, and decision making. Cognitive, Affective, & Behavioural Neuroscience, 2, 341–353]. In the present study, we investigate whether the latter findings were due to increased random responding [Franco-Watkins, A. M., Pashler, H., & Rickard, T. C. (2006). Does working memory load lead to greater impulsivity? Commentary on Hinson, Jameson, and Whitney’s (2003). Journal of Experimental Psychology: Learning, Memory & Cognition, 32, 443–447]. Participants were tested under Low Working Memory (LWM; n = 18) or High Working Memory (HWM; n = 17) conditions while performing the Reversed IGT in which punishment was immediate and reward delayed [Bechara, A., Dolan, S., & Hindes, A. (2002). Decision making and addiction (part II): Myopia for the future or hypersensitivity to reward? Neuropsychologia, 40, 1690–1705]. In support of a role for working memory in emotional decision making, compared to the LWM condition, participants in the HWM condition made significantly greater number of disadvantageous selections than that predicted by chance. Performance by the HWM group could not be fully explained by random responding.
ARTICLE UPDATE - Spatial frequencies or emotional effects?
Delplanque S, N'diaye K, Scherer K, Grandjean D.
Journal of Neuroscience Methods, in press
The influence of the emotional attributes of a visual scene on early perception processes remains a key question in contemporary affective neurosciences. The International Affective Picture System (IAPS; Lang et al., 2005) was developed to provide a set of standardized stimuli for experimental investigations of emotional processes. These stimuli have been widely used in brain activity investigations to study the influence of valence and/or arousal on visual processing. However, visual perception is strongly influenced by the physical properties of the images shown, especially their spatial frequency content, an aspect that has been unexpectedly neglected at large. In this study, we examine the complete set of IAPS with a discrete wavelet transform to highlight relations between the energy in different spatial frequencies and the emotional features of the pictures. Our results showed that these associations are weak when the complete dataset is considered, but for selected subsets of pictures, clear differences are present in both affective and spatial frequency content. The IAPS remains a powerful tool to explore emotional processing, but we strongly suggest that researchers use subsets of images that are controlled for the energy of their spatial frequencies when investigating emotional influence on visual processing.
Journal of Neuroscience Methods, in press
The influence of the emotional attributes of a visual scene on early perception processes remains a key question in contemporary affective neurosciences. The International Affective Picture System (IAPS; Lang et al., 2005) was developed to provide a set of standardized stimuli for experimental investigations of emotional processes. These stimuli have been widely used in brain activity investigations to study the influence of valence and/or arousal on visual processing. However, visual perception is strongly influenced by the physical properties of the images shown, especially their spatial frequency content, an aspect that has been unexpectedly neglected at large. In this study, we examine the complete set of IAPS with a discrete wavelet transform to highlight relations between the energy in different spatial frequencies and the emotional features of the pictures. Our results showed that these associations are weak when the complete dataset is considered, but for selected subsets of pictures, clear differences are present in both affective and spatial frequency content. The IAPS remains a powerful tool to explore emotional processing, but we strongly suggest that researchers use subsets of images that are controlled for the energy of their spatial frequencies when investigating emotional influence on visual processing.
ARTICLE UPDATE- Remembering the specific visual details of presented objects: Neuroimaging evidence for effects of emotion.
Kensinger EA, Schacter DL.
Neuropsychologia, in press
Memories can be retrieved with varied amounts of visual detail, and the emotional content of information can influence the likelihood that visual detail is remembered. In the present fMRI experiment (conducted with 19 adults scanned using a 3 T magnet), we examined the neural processes that correspond with recognition of the visual details of negative and neutral items. Results revealed that a region of the left fusiform gyrus corresponded with retrieval of visual details for both negative and neutral items. Activity in the amygdala and orbitofrontal cortex, in contrast, was related to retrieval of visual details only for negative items. Activity in these regions corresponded only with successful recognition, and not with false recognition, providing strong evidence that limbic engagement during retrieval does not correspond merely with a person's belief that detail has been recognized. Rather, limbic engagement appears to relate specifically to the successful recognition of information.
Neuropsychologia, in press
Memories can be retrieved with varied amounts of visual detail, and the emotional content of information can influence the likelihood that visual detail is remembered. In the present fMRI experiment (conducted with 19 adults scanned using a 3 T magnet), we examined the neural processes that correspond with recognition of the visual details of negative and neutral items. Results revealed that a region of the left fusiform gyrus corresponded with retrieval of visual details for both negative and neutral items. Activity in the amygdala and orbitofrontal cortex, in contrast, was related to retrieval of visual details only for negative items. Activity in these regions corresponded only with successful recognition, and not with false recognition, providing strong evidence that limbic engagement during retrieval does not correspond merely with a person's belief that detail has been recognized. Rather, limbic engagement appears to relate specifically to the successful recognition of information.
Thursday, July 19, 2007
ARTICLE UPDATE - Efficient Attentional Selection Predicts Distractor Devaluation: Event-related Potential Evidence for a Direct Link between Attention
Monika Kiss, Brian A. Goolsby, Jane E. Raymond, Kimron L. Shapiro, Laetitia Silvert, Anna C. Nobre, Nickolaos Fragopanagos, John G. Taylor and Martin Eimer
The Journal of Cognitive Neuroscience, 19, 1316-1322.
Links between attention and emotion were investigated by obtaining electrophysiological measures of attentional selectivity together with behavioral measures of affective evaluation. Participants were asked to rate faces that had just been presented as targets or distractors in a visual search task. Distractors were rated as less trustworthy than targets. To study the association between the efficiency of selective attention during visual search and subsequent emotional responses, the N2pc component was quantified as a function of evaluative judgments. Evaluation of distractor faces (but not target faces) covaried with selective attention. On trials where distractors were later judged negatively, the N2pc emerged earlier, demonstrating that attention was strongly biased toward target events, and distractors were effectively inhibited. When previous distractors were judged positively, the N2pc was delayed, indicating unfocused attention to the target and less distractor suppression. Variations in attentional selectivity across trials can predict subsequent emotional responses, strongly suggesting that attention is closely associated with subsequent affective evaluation.
The Journal of Cognitive Neuroscience, 19, 1316-1322.
Links between attention and emotion were investigated by obtaining electrophysiological measures of attentional selectivity together with behavioral measures of affective evaluation. Participants were asked to rate faces that had just been presented as targets or distractors in a visual search task. Distractors were rated as less trustworthy than targets. To study the association between the efficiency of selective attention during visual search and subsequent emotional responses, the N2pc component was quantified as a function of evaluative judgments. Evaluation of distractor faces (but not target faces) covaried with selective attention. On trials where distractors were later judged negatively, the N2pc emerged earlier, demonstrating that attention was strongly biased toward target events, and distractors were effectively inhibited. When previous distractors were judged positively, the N2pc was delayed, indicating unfocused attention to the target and less distractor suppression. Variations in attentional selectivity across trials can predict subsequent emotional responses, strongly suggesting that attention is closely associated with subsequent affective evaluation.
Monday, July 16, 2007
ARTICLE UPDATE - Language as context for the perception of emotion.
Barrett LF, Lindquist KA, Gendron M.
Trends in Cognitive Sciences, in press
In the blink of an eye, people can easily see emotion in another person's face. This fact leads many to assume that emotion perception is given and proceeds independently of conceptual processes such as language. In this paper we suggest otherwise and offer the hypothesis that language functions as a context in emotion perception. We review a variety of evidence consistent with the language-as-context view and then discuss how a linguistically relative approach to emotion perception allows for intriguing and generative questions about the extent to which language shapes the sensory processing involved in seeing emotion in another person's face.
Trends in Cognitive Sciences, in press
In the blink of an eye, people can easily see emotion in another person's face. This fact leads many to assume that emotion perception is given and proceeds independently of conceptual processes such as language. In this paper we suggest otherwise and offer the hypothesis that language functions as a context in emotion perception. We review a variety of evidence consistent with the language-as-context view and then discuss how a linguistically relative approach to emotion perception allows for intriguing and generative questions about the extent to which language shapes the sensory processing involved in seeing emotion in another person's face.
ARTICLE UPDATE - Emotional consciousness: A neural model of how cognitive appraisal and somatic perception interact to produce qualitative experience
Thagard P, Aubie B.
Consciousness and Cognition, in press
This paper proposes a theory of how conscious emotional experience is produced by the brain as the result of many interacting brain areas coordinated in working memory. These brain areas integrate perceptions of bodily states of an organism with cognitive appraisals of its current situation. Emotions are neural processes that represent the overall cognitive and somatic state of the organism. Conscious experience arises when neural representations achieve high activation as part of working memory. This theory explains numerous phenomena concerning emotional consciousness, including differentiation, integration, intensity, valence, and change.
Consciousness and Cognition, in press
This paper proposes a theory of how conscious emotional experience is produced by the brain as the result of many interacting brain areas coordinated in working memory. These brain areas integrate perceptions of bodily states of an organism with cognitive appraisals of its current situation. Emotions are neural processes that represent the overall cognitive and somatic state of the organism. Conscious experience arises when neural representations achieve high activation as part of working memory. This theory explains numerous phenomena concerning emotional consciousness, including differentiation, integration, intensity, valence, and change.
Tuesday, July 10, 2007
ARTICLE UPDATE - Trait anxiety modulates supraliminal and subliminal threat: Brain potential evidence for early and late processing influences
Li, Wen; Zinbarg, Richard E.; Paller, Ken A.
Cognitive, Affective, & Behavioral Neuroscience, 7, 25-36
Analysis of threat is thought to involve a "quick and dirty" stage in conjunction with slower processing that is more complete. We investigated both types of threat analysis by recording brain potentials in response to threat and neutral words. Personality testing was used to identify participants who were either high or low in trait anxiety (TA). An observed enhancement of occipital P1 potentials to threat words during an emotional Stroop task was interpreted as a signal of unconscious processing, since it was early, independent of whether word exposure was subliminal or supraliminal, and more prominent the higher the level of TA. Later positive potentials were also enhanced for threat versus neutral words, but the amplitude enhancement increased with higher TA only in the subliminal condition. These results suggest that unconscious analysis of threat is intensified in those prone to anxiety, as is a later stage of threat processing subject to dynamic interactions between automatic and strategic influences.
Cognitive, Affective, & Behavioral Neuroscience, 7, 25-36
Analysis of threat is thought to involve a "quick and dirty" stage in conjunction with slower processing that is more complete. We investigated both types of threat analysis by recording brain potentials in response to threat and neutral words. Personality testing was used to identify participants who were either high or low in trait anxiety (TA). An observed enhancement of occipital P1 potentials to threat words during an emotional Stroop task was interpreted as a signal of unconscious processing, since it was early, independent of whether word exposure was subliminal or supraliminal, and more prominent the higher the level of TA. Later positive potentials were also enhanced for threat versus neutral words, but the amplitude enhancement increased with higher TA only in the subliminal condition. These results suggest that unconscious analysis of threat is intensified in those prone to anxiety, as is a later stage of threat processing subject to dynamic interactions between automatic and strategic influences.
ARTICLE UPDATE - Cross-modal attention capture by affective stimuli: Evidence from event-related potentials
Keil, Andreas; Bradley, Margaret M.; Junghöfer, Markus; Russmann, Thomas; Lowenthal, William; Lang, Peter J.
Cognitive, Affective, & Behavioral Neuroscience, 7, 18-24.
The P3 component of the event-related potential (ERP) to an acoustic startle probe is modulated during picture viewing, with reduced P3 amplitude when participants view either pleasant or unpleasant, as opposed to neutral, pictures. We have interpreted this as reflecting capture of attentional resources by affective pictures, with fewer resources available for processing the secondary startle probe. In the present study, we tested this resource allocation hypothesis by presenting either pictures or sounds as foreground stimuli, with the prediction that P3 amplitude in response to secondary startle probes would be reduced for affectively engaging foregrounds regardless of modality. Using dense-array electroencephalography and a source estimation procedure, we observed that P3 amplitude was indeed smaller when startle probes were presented during emotional, as opposed to neutral, stimuli for both sound and picture foregrounds. Source modeling indicated a common frontocentral maximum of P3 modulation by affect. The data support the notion that emotionally arousing stimuli transmodally attract resources, leading to optimized processing of the affective stimuli at the cost of the processing of concurrent stimuli.
Cognitive, Affective, & Behavioral Neuroscience, 7, 18-24.
The P3 component of the event-related potential (ERP) to an acoustic startle probe is modulated during picture viewing, with reduced P3 amplitude when participants view either pleasant or unpleasant, as opposed to neutral, pictures. We have interpreted this as reflecting capture of attentional resources by affective pictures, with fewer resources available for processing the secondary startle probe. In the present study, we tested this resource allocation hypothesis by presenting either pictures or sounds as foreground stimuli, with the prediction that P3 amplitude in response to secondary startle probes would be reduced for affectively engaging foregrounds regardless of modality. Using dense-array electroencephalography and a source estimation procedure, we observed that P3 amplitude was indeed smaller when startle probes were presented during emotional, as opposed to neutral, stimuli for both sound and picture foregrounds. Source modeling indicated a common frontocentral maximum of P3 modulation by affect. The data support the notion that emotionally arousing stimuli transmodally attract resources, leading to optimized processing of the affective stimuli at the cost of the processing of concurrent stimuli.
Monday, July 09, 2007
ARTICLE UPDATE - Modulation of anticipatory emotion and perception processing by cognitive control.
Herwig U, Baumgartner T, Kaffenberger T, Brühl A, Kottlow M, Schreiter-Gasser U, Abler B, Jäncke L, Rufer M.
NeuroImage, in press
Strategies of cognitive control are helpful in reducing anxiety experienced during anticipation of unpleasant or potentially unpleasant events. We investigated the associated cerebral information processing underlying the use of a specific cognitive control strategy during the anticipation of affect-laden events. Using functional magnetic resonance imaging, we examined differential brain activity during anticipation of events of unknown and negative emotional valence in a group of eighteen healthy subjects that used a cognitive control strategy, similar to "reality checking" as used in psychotherapy, compared with a group of sixteen subjects that did not exert cognitive control. While expecting unpleasant stimuli, the "cognitive control" group showed higher activity in left medial and dorsolateral prefrontal cortex areas but reduced activity in the left extended amygdala, pulvinar/lateral geniculate nucleus and fusiform gyrus. Cognitive control during the "unknown" expectation was associated with reduced amygdalar activity as well and further with reduced insular and thalamic activity. The amygdala activations associated with cognitive control correlated negatively with the reappraisal scores of an emotion regulation questionnaire. The results indicate that cognitive control of particularly unpleasant emotions is associated with elevated prefrontal cortex activity that may serve to attenuate emotion processing in for instance amygdala, and, notably, in perception related brain areas.
NeuroImage, in press
Strategies of cognitive control are helpful in reducing anxiety experienced during anticipation of unpleasant or potentially unpleasant events. We investigated the associated cerebral information processing underlying the use of a specific cognitive control strategy during the anticipation of affect-laden events. Using functional magnetic resonance imaging, we examined differential brain activity during anticipation of events of unknown and negative emotional valence in a group of eighteen healthy subjects that used a cognitive control strategy, similar to "reality checking" as used in psychotherapy, compared with a group of sixteen subjects that did not exert cognitive control. While expecting unpleasant stimuli, the "cognitive control" group showed higher activity in left medial and dorsolateral prefrontal cortex areas but reduced activity in the left extended amygdala, pulvinar/lateral geniculate nucleus and fusiform gyrus. Cognitive control during the "unknown" expectation was associated with reduced amygdalar activity as well and further with reduced insular and thalamic activity. The amygdala activations associated with cognitive control correlated negatively with the reappraisal scores of an emotion regulation questionnaire. The results indicate that cognitive control of particularly unpleasant emotions is associated with elevated prefrontal cortex activity that may serve to attenuate emotion processing in for instance amygdala, and, notably, in perception related brain areas.
ARTICLE UPDATE - A lasting post-stimulus activation on dorsolateral prefrontal cortex is produced when processing valence and arousal in visual affect
León-Carrión J, MartÃn-RodrÃguez JF, Damas-López J, Pourrezai K, Izzetoglu K, Barroso Y Martin JM, DomÃnguez-Morales MR.
Neuroscience Letters, in press
This paper introduces a new paradigm in the study of emotional processes through functional neuroimaging. We study whether the valence and arousal of visual stimuli influence neuroimaging of the evoked hemodynamic changes. Using functional near-infrared spectroscopy (fNIRS), we investigate evoked-cerebral blood oxygenation (CBO) changes in dorsolateral prefrontal cortex (DLPFC) during direct exposure to different emotion-eliciting stimuli ('on' period), and during the period directly following stimulus cessation ('off' period). We hypothesize that the evoked-CBO, rather than return to baseline after stimulus cessation, would show either overshoot or undershoot. The study includes 30 healthy subjects and a total of 9 stimuli, which consist of video-clips with different emotional content. The total sample of trials studied (270) is classified according to the valence and arousal ratings given by the subjects. Results show a more robust activation in DLPFC during the 'off' period than during the 'on' period, depending on the subjective degree of arousal given to the stimulus. Our findings provide the first fNIRS evidence showing that an increment in subjective arousal leads to activation in DLPFC which persists after stimulus cessation and this does not occur with non-arousing stimuli. Neuroimaging studies must consider the duration and affective dimensions of the stimulus as well as the duration of the scanning to specify how much of the recorded response is analyzed. Not accounting for this difference may contribute to confusion in the data interpretation.
Neuroscience Letters, in press
This paper introduces a new paradigm in the study of emotional processes through functional neuroimaging. We study whether the valence and arousal of visual stimuli influence neuroimaging of the evoked hemodynamic changes. Using functional near-infrared spectroscopy (fNIRS), we investigate evoked-cerebral blood oxygenation (CBO) changes in dorsolateral prefrontal cortex (DLPFC) during direct exposure to different emotion-eliciting stimuli ('on' period), and during the period directly following stimulus cessation ('off' period). We hypothesize that the evoked-CBO, rather than return to baseline after stimulus cessation, would show either overshoot or undershoot. The study includes 30 healthy subjects and a total of 9 stimuli, which consist of video-clips with different emotional content. The total sample of trials studied (270) is classified according to the valence and arousal ratings given by the subjects. Results show a more robust activation in DLPFC during the 'off' period than during the 'on' period, depending on the subjective degree of arousal given to the stimulus. Our findings provide the first fNIRS evidence showing that an increment in subjective arousal leads to activation in DLPFC which persists after stimulus cessation and this does not occur with non-arousing stimuli. Neuroimaging studies must consider the duration and affective dimensions of the stimulus as well as the duration of the scanning to specify how much of the recorded response is analyzed. Not accounting for this difference may contribute to confusion in the data interpretation.
ARTICLE UPDATE - The voice of emotion: an FMRI study of neural responses to angry and happy vocal expressions.
Johnstone T, van Reekum CM, Oakes TR, Davidson RJ.
Social Cognitive Affective Neuroscience, 1, 242-249
The human voice is one of the principal conveyers of social and affective communication. Yet relatively little is known about the neural circuitry that supports the recognition of different vocally expressed emotions. We conducted an FMRI study to examine the brain responses to vocal expressions of anger and happiness, and to test whether specific brain regions showed preferential engagement in the processing of one emotion over the other. We also tested the extent to which simultaneously presented facial expressions of the same or different emotions would enhance brain responss, and to what degree such responses depend on attention towards the vocal expression. Forty healthy individuals were scanned while listening to vocal expressions of anger or happiness, while at the same time watching congruent or discrepant facial expressions. Happy voices elicited significantly more activation than angry voices in right anterior and posterior middle temporal gyrus (MTG), left posterior MTG and right inferior frontal gyrus. Furthermore, for the left MTG region, happy voices were related to higher activation only when paired with happy faces. Activation in the left insula, left amygdala and hippocampus, and rostral anterior cingulate cortex showed an effect of selectively attending to the vocal stimuli. Our results identify a network of regions implicated in the processing of vocal emotion, and suggest a particularly salient role for vocal expressions of happiness.
Social Cognitive Affective Neuroscience, 1, 242-249
The human voice is one of the principal conveyers of social and affective communication. Yet relatively little is known about the neural circuitry that supports the recognition of different vocally expressed emotions. We conducted an FMRI study to examine the brain responses to vocal expressions of anger and happiness, and to test whether specific brain regions showed preferential engagement in the processing of one emotion over the other. We also tested the extent to which simultaneously presented facial expressions of the same or different emotions would enhance brain responss, and to what degree such responses depend on attention towards the vocal expression. Forty healthy individuals were scanned while listening to vocal expressions of anger or happiness, while at the same time watching congruent or discrepant facial expressions. Happy voices elicited significantly more activation than angry voices in right anterior and posterior middle temporal gyrus (MTG), left posterior MTG and right inferior frontal gyrus. Furthermore, for the left MTG region, happy voices were related to higher activation only when paired with happy faces. Activation in the left insula, left amygdala and hippocampus, and rostral anterior cingulate cortex showed an effect of selectively attending to the vocal stimuli. Our results identify a network of regions implicated in the processing of vocal emotion, and suggest a particularly salient role for vocal expressions of happiness.
ARTICLE UPDATE - Threat sensitivity as assessed by automatic amygdala response to fearful faces predicts speed of visual search for facial expression.
Ohrmann P, Rauch AV, Bauer J, Kugel H, Arolt V, Heindel W, Suslow T.
Experimental Brain Research, in press
It has been argued that the amygdala represents an integral component of a vigilance system that is primarily involved in the perception of ambiguous stimuli of biological relevance. The present investigation was conducted to examine the relationship between automatic amygdala responsivity to fearful faces which may be interpreted as an index of trait-like threat sensitivity and spatial processing characteristics of facial emotions. During 3T fMRI scanning, pictures of human faces bearing fearful, angry, and happy expressions were presented to 20 healthy volunteers using a backward masking procedure based on neutral facial expressions. Subsequently, a computer-based face-in-the-crowd task using schematic face stimuli was administered. The neural response of the (right) amygdala to masked fearful faces correlated consistently with response speed to negative and neutral faces. Neither amygdala activation during the masked presentation of angry faces nor amygdala activation during the presentation of happy faces was correlated with any of the response latencies in the face-in-the-crowd task. Our results suggest that amygdala responsivity to masked facial expression is differentially related to the general visual search speed for facial expression. Neurobiologically defined threat sensitivity seems to represent an important determinant of visual scanning behaviour.
Experimental Brain Research, in press
It has been argued that the amygdala represents an integral component of a vigilance system that is primarily involved in the perception of ambiguous stimuli of biological relevance. The present investigation was conducted to examine the relationship between automatic amygdala responsivity to fearful faces which may be interpreted as an index of trait-like threat sensitivity and spatial processing characteristics of facial emotions. During 3T fMRI scanning, pictures of human faces bearing fearful, angry, and happy expressions were presented to 20 healthy volunteers using a backward masking procedure based on neutral facial expressions. Subsequently, a computer-based face-in-the-crowd task using schematic face stimuli was administered. The neural response of the (right) amygdala to masked fearful faces correlated consistently with response speed to negative and neutral faces. Neither amygdala activation during the masked presentation of angry faces nor amygdala activation during the presentation of happy faces was correlated with any of the response latencies in the face-in-the-crowd task. Our results suggest that amygdala responsivity to masked facial expression is differentially related to the general visual search speed for facial expression. Neurobiologically defined threat sensitivity seems to represent an important determinant of visual scanning behaviour.
Monday, July 02, 2007
Re-visit somatic marker hypothesis
Please refer to this blog to view two discussions about the validity of somatic marker hypothesis proposed by Damasio.
Discussion 1
Discussion 2
Discussion 1
Discussion 2
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