Neuroimaging support for discrete neural correlates of basic emotions: a voxel-based meta-analysis

Qualitative Analysis of Emotions: Fear and Thrill

People can speak, and this provides opportunities to analyze human emotions using perceived experiences communicated via language, as well as through measurement and imaging techniques that are also applicable to other higher animal species. Here I compare four qualitative methodological approaches to test if, and how, thrill depends on fear. I use eight high-risk, high-skill, real-life outdoor adventure recreation activities to provide the test circumstances. I present data from: >4000 person-days of participant observation; interviews with 40 expert practitioners; retrospective autoethnography of 50 critical incidents over 4 decades; and experimental autoethnography of 60 events. Results from different methods are congruent, but different approaches yield different insights. The principal findings are as follows. Individuals differ in their fear and thrill responses. The same individual may have different responses on different occasions. Fear boosts performance, but panic causes paralysis. Anxiety or apprehension prior to a risky action or event differs from fear experienced during the event itself. The intensity of pre-event fear generally increases with the immediacy of risk to life, and time to contemplate that risk. Fear must be faced, assessed and overcome in order to act. Thrill can occur either during or after a high-risk event. Thrill can occur without fear, and fear without thrill. Below a lower threshold of perceived risk, thrill can occur without fear. Between a lower and upper threshold, thrill increases with fear. Beyond the upper threshold, thrill vanishes but fear remains. This there is a sawtooth relation between fear and thrill. Perceived danger generates intense focus and awareness. Fear and other emotions can disappear during intense concentration and focus. Under high risk, the usual emotional sequence is fear before the action or event, then focus during the action or event, then thrill, relief, or triumph afterward. The emotionless state persists only during the most intense concentration. For events long enough to differentiate time within the events, fear and thrill can arise and fade in different fine-scale sequences.

Frontal negativity: An electrophysiological index of interpersonal guilt

The present study aimed to reveal the temporal course and electrophysiological correlates of interpersonal guilt. Human participants were asked to perform multiple rounds of a dot-estimation task with their partners, while event-related potential being recorded. The paired participants were informed that they would win money if both responded correctly; otherwise, both of them would lose money. The feeling of guilt in Self-Wrong condition (SW) was significantly higher than that in Both-Wrong and Partner-Wrong conditions. At approximately 350 ms after the onset of feedback presentation, greater negativities were observed in the frontal regions in the guilt condition (i.e., SW) than those in the non-guilt condition. The guilt-modulated frontal negativity might reflect the interactions of self-reflection, condemnation, and negative emotion.

What Is the Effect of Basic Emotions on Directed Forgetting? Investigating the Role of Basic Emotions in Memory

Studies presenting memory-facilitating effect of emotions typically focused on affective dimensions of arousal and valence. Little is known, however, about the extent to which stimulus-driven basic emotions could have distinct effects on memory. In the present paper we sought to examine the modulatory effect of disgust, fear, and sadness on intentional remembering and forgetting using widely used item-method directed forgetting (DF) paradigm. Eighteen women underwent fMRI scanning during encoding phase in which they were asked either to remember (R) or to forget (F) pictures. In the test phase all previously used stimuli were re-presented together with the same number of new pictures and participants had to categorize them as old or new, irrespective of the F/R instruction. On the behavioral level we found a typical DF effect, i.e., higher recognition rates for to-be-remembered (TBR) items than to-be-forgotten (TBF) ones for both neutral and emotional categories. Emotional stimuli had higher recognition rate than neutral ones, while among emotional those eliciting disgust produced highest recognition, but at the same time induced more false alarms. Therefore, when false alarm corrected recognition was examined the DF effect was equally strong irrespective of emotion. Additionally, even though subjects rated disgusting pictures as more arousing and negative than other picture categories, logistic regression on the item level showed that the effect of disgust on recognition memory was stronger than the effect of arousal or valence. On the neural level, ROI analyses (with valence and arousal covariates) revealed that correctly recognized disgusting stimuli evoked the highest activity in the left amygdala compared to all other categories. This structure was also more activated for remembered vs. forgotten stimuli, but only in case of disgust or fear eliciting pictures. Our findings, despite several limitations, suggest that disgust have a special salience in memory relative to other negative emotions, which cannot be put down to differences in arousal or valence. The current results thereby support the suggestion that a purely dimensional model of emotional influences on cognition might not be adequate to account for observed effects.

The Discrete Emotions Questionnaire: A New Tool for Measuring State Self-Reported Emotions

Several discrete emotions have broad theoretical and empirical importance, as shown by converging evidence from diverse areas of psychology, including facial displays, developmental behaviors, and neuroscience. However, the measurement of these states has not progressed along with theory, such that when researchers measure subjectively experienced emotions, they commonly rely on scales assessing broad dimensions of affect (positivity and negativity), rather than discrete emotions. The current manuscript presents four studies that validate a new instrument, the Discrete Emotions Questionnaire (DEQ), that is sensitive to eight distinct state emotions: anger, disgust, fear, anxiety, sadness, happiness, relaxation, and desire. Emotion theory supporting the importance of distinguishing these specific emotions is reviewed.

Contributions of the Central Extended Amygdala to Fear and Anxiety

It is widely thought that phasic and sustained responses to threat reflect dissociable circuits centered on the central nucleus of the amygdala (Ce) and the bed nucleus of the stria terminalis (BST), the two major subdivisions of the central extended amygdala. Early versions of this hypothesis remain highly influential and have been incorporated into the National Institute of Mental Health Research Research Domain Criteria framework. However, new observations encourage a different perspective. Anatomical studies show that the Ce and BST form a tightly interconnected unit, where different kinds of threat-relevant information can be integrated and used to assemble states of fear and anxiety. Imaging studies in humans and monkeys show that the Ce and BST exhibit similar functional profiles. Both regions are sensitive to a range of aversive challenges, including uncertain or temporally remote threat; both covary with concurrent signs and symptoms of fear and anxiety; both show phasic responses to short-lived threat; and both show heightened activity during sustained exposure to diffusely threatening contexts. Mechanistic studies demonstrate that both regions can control the expression of fear and anxiety during sustained exposure to diffuse threat. These observations compel a reconsideration of the central extended amygdala's contributions to fear and anxiety and its role in neuropsychiatric disease.

Differences in gray matter structure correlated to nationalism and patriotism

Nationalism and patriotism both entail positive evaluations of one's nation. However, the former inherently involves derogation of other nations, whereas the latter is independent of comparisons with other nations. We used voxel-based morphometry and psychological measures and determined nationalism and patriotism's association with gray matter density (rGMD) and their cognitive nature in healthy individuals (433 men and 344 women; age, 20.7 ± 1.9 years) using whole-brain multiple regression analyses and post hoc analyses. We found higher nationalism associated with greater rGMD in (a) areas of the posterior cingulate cortex and greater rGMD in (b) the orbitofrontal cortex, and smaller rGMD in (c) the right amygdala area. Furthermore, we found higher patriotism associated with smaller rGMD in the (d) rostrolateral prefrontal cortex. Post hoc analyses revealed the mean rGMD of the cluster (a) associated with compassion, that of (b) associated with feeling of superiority, that of (c) associated with suicide ideation, and that of (d) associated with quality of life. These results indicate that individual nationalism may be mediated by neurocognitive mechanisms in social-related areas and limbic neural mechanisms, whereas patriotism may be mediated by neurocognitive mechanisms in areas related to well-being.

Hidden sources of joy, fear, and sadness: Explicit versus implicit neural processing of musical emotions

Music is often used to regulate emotions and mood. Typically, music conveys and induces emotions even when one does not attend to them. Studies on the neural substrates of musical emotions have, however, only examined brain activity when subjects have focused on the emotional content of the music. Here we address with functional magnetic resonance imaging (fMRI) the neural processing of happy, sad, and fearful music with a paradigm in which 56 subjects were instructed to either classify the emotions (explicit condition) or pay attention to the number of instruments playing (implicit condition) in 4-s music clips. In the implicit vs. explicit condition, stimuli activated bilaterally the inferior parietal lobule, premotor cortex, caudate, and ventromedial frontal areas. The cortical dorsomedial prefrontal and occipital areas activated during explicit processing were those previously shown to be associated with the cognitive processing of music and emotion recognition and regulation. Moreover, happiness in music was associated with activity in the bilateral auditory cortex, left parahippocampal gyrus, and supplementary motor area, whereas the negative emotions of sadness and fear corresponded with activation of the left anterior cingulate and middle frontal gyrus and down-regulation of the orbitofrontal cortex. Our study demonstrates for the first time in healthy subjects the neural underpinnings of the implicit processing of brief musical emotions, particularly in frontoparietal, dorsolateral prefrontal, and striatal areas of the brain.

Short-term group cognitive behavior therapy contributes to recovery from mild depression: Evidence from functional and structural MRI

We used the functional and structural magnetic resonance imaging to explore the neural correlates of response to group cognitive behavioral therapy (CBT) in mild depression. College students with mild depressive symptoms participated in our 4-week group CBT training. The behavioral results showed that depression symptoms decreased after participation in group CBT. After the training, the gray matter volume (GMV) in the right middle frontal gyrus (MFG) increased and amplitude of low-frequency fluctuations (ALFF) decreased. In addition, GMV in the left postcentral gyrus decreased after the group CBT. Moreover, the increase of percentage change in the right MFG was positively correlated with the decrease of the Beck Depression Inventory (BDI) score, while less decrease in percentage change in the left postcentral gyrus was significantly correlated with greater decrease of BDI score. Finally, after the training, functional connectivity between the right MFG and the insula decreased, while the connectivity between the left postcentral gyrus and the parahippocampal gyrus increased. These findings suggested that short-term participation in group CBT had an effective impact on mild depression. It contributed to decreasing negative bias (salience detection for negative stimuli).

Brain Structural Correlates of Emotion Recognition in Psychopaths

Individuals with psychopathy present deficits in the recognition of facial emotional expressions. However, the nature and extent of these alterations are not fully understood. Furthermore, available data on the functional neural correlates of emotional face recognition deficits in adult psychopaths have provided mixed results. In this context, emotional face morphing tasks may be suitable for clarifying mild and emotion-specific impairments in psychopaths. Likewise, studies exploring corresponding anatomical correlates may be useful for disentangling available neurofunctional evidence based on the alleged neurodevelopmental roots of psychopathic traits. We used Voxel-Based Morphometry and a morphed emotional face expression recognition task to evaluate the relationship between regional gray matter (GM) volumes and facial emotion recognition deficits in male psychopaths. In comparison to male healthy controls, psychopaths showed deficits in the recognition of sad, happy and fear emotional expressions. In subsequent brain imaging analyses psychopaths with better recognition of facial emotional expressions showed higher volume in the prefrontal cortex (orbitofrontal, inferior frontal and dorsomedial prefrontal cortices), somatosensory cortex, anterior insula, cingulate cortex and the posterior lobe of the cerebellum. Amygdala and temporal lobe volumes contributed to better emotional face recognition in controls only. These findings provide evidence suggesting that variability in brain morphometry plays a role in accounting for psychopaths’ impaired ability to recognize emotional face expressions, and may have implications for comprehensively characterizing the empathy and social cognition dysfunctions typically observed in this population of subjects.

Insular atrophy and diminished disgust reactivity

Disgust is an emotion that helps us deal with potential contamination (Rozin & Fallon, 1987). It produces a distinctive facial expression (e.g., wrinkled nose) and a physiological response that is accompanied by strong visceral sensations (e.g., nausea). Given the important role that the anterior insula plays in processing and integrating visceral information (Craig, 2009), it is likely to be centrally involved in disgust. Despite this, few studies have examined the link between insular degeneration and the experience, physiology, and expression of disgust. We studied a group that was heterogeneous in terms of insular damage: 84 patients with neurodegenerative diseases (i.e., frontotemporal dementia, corticobasal syndrome, progressive supranuclear palsy, Alzheimer's disease) and 29 controls. Subjects viewed films that elicit high levels of disgust and sadness. Emotional reactivity was assessed using self-report, peripheral physiology, and facial behavior. Regional brain volumes (insula, putamen, pallidum, caudate, and amygdala) were determined from structural MRIs using the FreeSurfer method. Results indicated that smaller insular volumes were associated with reduced disgust responding in self-report and physiological reactivity, but not in facial behavior. In terms of the specificity of these findings, insular volume did not predict sadness reactivity, and disgust reactivity was not predicted by putamen, pallidum, and caudate volumes (lower self-reported disgust was associated with smaller amygdala volume). These findings underscore the central role of the insula in the experience and physiology of disgust. (PsycINFO Database Record

Decoding the Nature of Emotion in the Brain

A central, unresolved problem in affective neuroscience is understanding how emotions are represented in nervous system activity. After prior localization approaches largely failed, researchers began applying multivariate statistical tools to reconceptualize how emotion constructs might be embedded in large-scale brain networks. Findings from pattern analyses of neuroimaging data show that affective dimensions and emotion categories are uniquely represented in the activity of distributed neural systems that span cortical and subcortical regions. Results from multiple-category decoding studies are incompatible with theories postulating that specific emotions emerge from the neural coding of valence and arousal. This 'new look' into emotion representation promises to improve and reformulate neurobiological models of affect.

Ratings for emotion film clips

Film clips are widely utilized to elicit emotion in a variety of research studies. Normative ratings for scenes selected for these purposes support the idea that selected clips correspond to the intended target emotion, but studies reporting normative ratings are limited. Using an ethnically diverse sample of college undergraduates, selected clips were rated for intensity, discreteness, valence, and arousal. Variables hypothesized to affect the perception of stimuli (i.e., gender, race-ethnicity, and familiarity) were also examined. Our analyses generally indicated that males reacted strongly to positively valenced film clips, whereas females reacted more strongly to negatively valenced film clips. Caucasian participants tended to react more strongly to the film clips, and we found some variation by race-ethnicity across target emotions. Finally, familiarity with the films tended to produce higher ratings for positively valenced film clips, and lower ratings for negatively valenced film clips. These findings provide normative ratings for a useful set of film clips for the study of emotion, and they underscore factors to be considered in research that utilizes scenes from film for emotion elicitation.

Clear signals or mixed messages: inter-individual emotion congruency modulates brain activity underlying affective body perception

The neural basis of emotion perception has mostly been investigated with single face or body stimuli. However, in daily life one may also encounter affective expressions by groups, e.g. an angry mob or an exhilarated concert crowd. In what way is brain activity modulated when several individuals express similar rather than different emotions? We investigated this question using an experimental design in which we presented two stimuli simultaneously, with same or different emotional expressions. We hypothesized that, in the case of two same-emotion stimuli, brain activity would be enhanced, while in the case of two different emotions, one emotion would interfere with the effect of the other. The results showed that the simultaneous perception of different affective body expressions leads to a deactivation of the amygdala and a reduction of cortical activity. It was revealed that the processing of fearful bodies, compared with different-emotion bodies, relied more strongly on saliency and action triggering regions in inferior parietal lobe and insula, while happy bodies drove the occipito-temporal cortex more strongly. We showed that this design could be used to uncover important differences between brain networks underlying fearful and happy emotions. The enhancement of brain activity for unambiguous affective signals expressed by several people simultaneously supports adaptive behaviour in critical situations.

Processing of emotional stimuli is reflected by modulations of beta band activity in the subgenual anterior cingulate cortex in patients with treatment resistant depression

Deep brain stimulation (DBS) of the subgenual anterior cingulate cortex (sgACC) has emerged as a new therapeutic option in patients with treatment resistant depression (TRD). At the same time, DBS offers a unique opportunity as an innovative research tool to study brain function in vivo Indirect measures of brain function such as positron-emission-tomography imaging findings have revealed a hypermetabolism in the sgACC area in patients with TRD that normalizes in parallel with treatment response to DBS. We used direct intracranial recordings via implanted DBS electrodes to study the neuronal oscillatory activity in the sgACC area during a picture viewing task including emotional and neutral stimuli in eight patients with TRD who underwent DBS.We found a stimulus-induced decrease in beta-band and increase in gamma-band activity, with a main effect of valence for event-related desynchronisation in the beta-frequency range (14-30 Hz). Unpleasant stimuli induced the strongest and most sustained beta-power decrease. The degree of beta-band modulation upon emotional stimuli correlated with the patients' rating of stimulus valence. Our findings confirm the involvement of the sgACC area in emotional processing that was more enhanced for unpleasant stimuli. Moreover, stimulus evaluation may be encoded by modulations of beta-band activity.

Cross-modal representations of first-hand and vicarious pain, disgust and fairness in insular and cingulate cortex

The anterior insula (AI) and mid-anterior cingulate cortex (mACC) have repeatedly been implicated in first-hand and vicarious experiences of pain, disgust and unfairness. However, it is debated whether these regions process different aversive events through a common modality-independent code, reflecting the shared unpleasantness of the experiences or through independent modality-specific representations. Using functional magnetic resonance imaging, we subjected 19 participants (and 19 confederates) to equally unpleasant painful and disgusting stimulations, as well as unfair monetary treatments. Multivoxel pattern analysis identified modality-independent activation maps in the left AI and mACC, pointing to common coding of affective unpleasantness, but also response patterns specific for the events' sensory properties and the person to whom it was addressed, particularly in the right AI. Our results provide evidence of both functional specialization and integration within AI and mACC, and support a comprehensive role of this network in processing aversive experiences for self and others.

Effect of repetitive transcranial magnetic stimulation on mood in healthy subjects

Background

High frequency repetitive transcranial magnetic stimulation (rTMS) of the left dorsolateral prefrontal cortex (DLPFC) has shown significant efficiency in the treatment of resistant depression. However in healthy subjects, the effects of rTMS remain unclear.

Objective

Our aim was to determine the impact of 10 sessions of rTMS applied to the DLPFC on mood and emotion recognition in healthy subjects.

Design

In a randomised double-blind study, 20 subjects received 10 daily sessions of active (10 Hz frequency) or sham rTMS. The TMS coil was positioned on the left DLPFC through neuronavigation. Several dimensions of mood and emotion processing were assessed at baseline and after rTMS with clinical scales, visual analogue scales (VASs), and the Ekman 60 faces test.

Results

The 10 rTMS sessions targeting the DLPFC were well tolerated. No significant difference was found between the active group and the control group for clinical scales and the Ekman 60 faces test. Compared to the control group, the active rTMS group presented a significant improvement in their adaptation to daily life, which was assessed through VAS.

Conclusion

This study did not show any deleterious effect on mood and emotion recognition of 10 sessions of rTMS applied on the DLPFC in healthy subjects. This study also suggested a positive effect of rTMS on quality of life.

The cross-mammalian neurophenomenology of primal emotional affects: From animal feelings to human therapeutics

The neural correlates of human emotions are easy to harvest. In contrast, the neural constitution of emotional feelings in humans has resisted systematic scientific analysis. This review summarizes how preclinical affective neuroscience initiatives are making progress in decoding the neural nature of such feelings in animal brains. This has been achieved by studying the rewarding and punishing effects of deep brain stimulation (DBS) of subcortical emotional networks (labeled SEEING, RAGE, FEAR, LUST, CARE, PANIC, and PLAY systems) that evoke distinct emotion action patterns, as well as rewarding and punishing effects in animals. The implications of this knowledge for development of new psychiatric interventions, especially depression, are discussed. Three new antidepressive therapeutics arising from this work are briefly noted: 1) DBS of the medial forebrain bundle (MFB) in humans, 2) reduction of psychological pain that may arise from excessive PANIC arousal, and 3) facilitation of social joy through the study of social play in rats The overall argument is that we may more readily develop new psychiatric interventions through preclinical models if we take animal emotional feelings seriously, as opposed to just behavioral changes, as targets for development of new treatments.

Involvement of the Ventrolateral Prefrontal Cortex in Learning Others' Bad Reputations and Indelible Distrust

A bad reputation can persistently affect judgments of an individual even when it turns out to be invalid and ought to be disregarded. Such indelible distrust may reflect that the negative evaluation elicited by a bad reputation transfers to a person. Consequently, the person him/herself may come to activate this negative evaluation irrespective of the accuracy of the reputation. If this theoretical model is correct, an evaluation-related brain region will be activated when witnessing a person whose bad reputation one has learned about, regardless of whether the reputation is deemed valid or not. Here, we tested this neural hypothesis with functional magnetic resonance imaging (fMRI). Participants memorized faces paired with either a good or a bad reputation. Next, they viewed the faces alone and inferred whether each person was likely to cooperate, first while retrieving the reputations, and then while trying to disregard them as false. A region of the left ventrolateral prefrontal cortex (vlPFC), which may be involved in negative evaluation, was activated by faces previously paired with bad reputations, irrespective of whether participants attempted to retrieve or disregard these reputations. Furthermore, participants showing greater activity of the left ventrolateral prefrontal region in response to the faces with bad reputations were more likely to infer that these individuals would not cooperate. Thus, once associated with a bad reputation, a person may elicit evaluation-related brain responses on their own, thereby evoking distrust independently of their reputation.

Betel quid dependence is associated with functional connectivity changes of the anterior cingulate cortex: a resting-state fMRI study

OBJECTIVE

It is generally acknowledged that drug dependence is connected with abnormal functional organization in the individual's brain. The present study aimed to identify the anterior cingulate cortex (ACC) abnormality with the cerebral networks involved in betel quid dependence (BQD) by resting-state functional connectivity (rsFC) using functional magnetic resonance imaging (fMRI).

METHODS

With fMRI data measured from 33 resting-state BQD individuals and 32 non-addicted and age-, sex-, education-matched healthy controls, we inquired into the BQD-related changes in FC between the regions of ACC with the whole brain involved in BQD individuals using a region of interest vised method, and to identify the relation of the alteration with the severity of BQD and duration.

RESULTS

Compared to controls, the BQD group showed increased connectivity from ACC to the regions of the reward network (brainstem including midbrain regions such as the ventral tegmental area and pons, caudate, thalamus) and cerebellum. Decreased connectivity was observed in the BQD group in regions from ACC to the default mode network (medial prefrontal cortex and precuneus) and para Hippocampal/hypothalamus. Specifically, the BQD scale was positively correlated with increased FC of right ACC to left thalamus and left ACC to pons; the durations were negatively correlated with FC of right ACC to left precuneus.

CONCLUSION

These disturbances in rsFC from ACC to the reward network and DMN revealed by fMRI may have a key function in providing insights into the neurological pathophysiology underlying BQD-associated executive dysfunction and disinhibition. These findings may contribute to our better understanding of the mechanisms underlying BQD.

Decreased sleep duration is associated with increased fMRI responses to emotional faces in children

In adults and children, sleep loss is associated with affective dysregulation and increased responsivity to negative stimuli. Adult functional neuroimaging (fMRI) studies have demonstrated associations between restricted sleep and neural alterations in the amygdala and reward circuitry when viewing emotional picture and face stimuli. Despite this, few studies have examined the associations between short sleep duration and emotional responsivity in typically developing children, and no studies have investigated this relationship using fMRI. The current study examined the relationship between sleep duration and fMRI activation to emotional facial expressions in 15 male children (ages 7-11 years). During fMRI scanning, subjects viewed and made perceptual judgments regarding negative, neutral, and positive emotional faces. Maternal reported child sleep duration was negatively associated with (a) activation in the bilateral amygdala, left insula, and left temporal pole activation when viewing negative (i.e., fearful, disgust) vs. neutral faces, (b) right orbitofrontal and bilateral prefrontal activation when viewing disgust vs. neutral faces, and (c) bilateral orbitofrontal, right anterior cingulate, and left amygdala activation when viewing happy vs. neutral faces. Consistent with our prediction, we also noted that emotion-dependent functional connectivity between the bilateral amygdala and prefrontal cortex, cingulate, fusiform, and occipital cortex was positively associated with sleep duration. Paralleling similar studies in adults, these findings collectively suggest that decreased sleep duration in school-aged children may contribute to enhanced reactivity of brain regions involved in emotion and reward processing, as well as decreased emotion-dependent functional connectivity between the amygdala and brain regions associated with emotion regulation.

Attention to emotional stimuli in borderline personality disorder - a review of the influence of dissociation, self-reference, and psychotherapeutic interventions

Interactions between attention and processing of emotional stimuli shed light on both sensitivity to emotional stimuli as well as emotion dysregulation. Both of the latter processes have been proposed as central characteristics of altered emotion processing in those with borderline personality disorder (BPD). This review first summarizes the conflicting behavioural, psychophysiological and neuroimaging evidence for the hypothesis that emotional dysregulation should be reflected by higher distractibility through emotional stimuli in those with BPD. Dissociation, self-reference, as well as symptom severity modulated by psychotherapeutic interventions are proposed to help clarify divergent findings. Data suggest an association of dissociation with impaired task continuation during the presentation of interfering emotional and neutral stimuli, as well as high recruitment of neuronal attention networks together with a blunted emotional response. Considering self-reference, evidence suggests that negative rather than positive information may be more self-relevant to those with BPD. This may be due to a negative self-concept and self-evaluation. Social or trauma-relevant information attracts more attention from individuals with BPD and thus suggests higher self-relevance. After psychotherapeutic interventions, initial evidence may indicate normalization of the way attention and emotional stimuli interact in BPD. When studying attention-emotion interactions in BPD, methodological heterogeneities regarding sample, task, and stimulus characteristics need to be considered. When doing so, dissociation, self-reference, and psychotherapeutic interventions offer promising targets for future studies on attention-emotion interactions in those with BPD. This could promote a deeper insight into the affected individuals' struggle with emotions.

Implicit and Explicit Attention to Pictures and Words: An fMRI-Study of Concurrent Emotional Stimulus Processing

The present study utilized functional magnetic resonance imaging (fMRI) to examine the neural processing of concurrently presented emotional stimuli under varying explicit and implicit attention demands. Specifically, in separate trials, participants indicated the category of either pictures or words. The words were placed over the center of the pictures and the picture-word compound-stimuli were presented for 1500 ms in a rapid event-related design. The results reveal pronounced main effects of task and emotion: the picture categorization task prompted strong activations in visual, parietal, temporal, frontal, and subcortical regions; the word categorization task evoked increased activation only in left extrastriate cortex. Furthermore, beyond replicating key findings regarding emotional picture and word processing, the results point to a dissociation of semantic-affective and sensory-perceptual processes for words: while emotional words engaged semantic-affective networks of the left hemisphere regardless of task, the increased activity in left extrastriate cortex associated with explicitly attending to words was diminished when the word was overlaid over an erotic image. Finally, we observed a significant interaction between Picture Category and Task within dorsal visual-associative regions, inferior parietal, and dorsolateral, and medial prefrontal cortices: during the word categorization task, activation was increased in these regions when the words were overlaid over erotic as compared to romantic pictures. During the picture categorization task, activity in these areas was relatively decreased when categorizing erotic as compared to romantic pictures. Thus, the emotional intensity of the pictures strongly affected brain regions devoted to the control of task-related word or picture processing. These findings are discussed with respect to the interplay of obligatory stimulus processing with task-related attentional control mechanisms.

Amygdala lesions in rhesus macaques decrease attention to threat

Evidence from animal and human studies has suggested that the amygdala plays a role in detecting threat and in directing attention to the eyes. Nevertheless, there has been no systematic investigation of whether the amygdala specifically facilitates attention to the eyes or whether other features can also drive attention via amygdala processing. The goal of the present study was to examine the effects of amygdala lesions in rhesus monkeys on attentional capture by specific facial features, as well as gaze patterns and changes in pupil dilation during free viewing. Here we show reduced attentional capture by threat stimuli, specifically the mouth, and reduced exploration of the eyes in free viewing in monkeys with amygdala lesions. Our findings support a role for the amygdala in detecting threat signals and in directing attention to the eye region of faces when freely viewing different expressions.

The amygdala in the medial temporal lobe of the human and non-human primate brain is known to process salient social stimuli and to mediate threat discrimination. Here, Dal Monte et al. show that rhesus monkeys with amygdala lesions have deficits in detecting threat signals and directing attention to the eye region of a conspecific's face.

The structural neural substrate of subjective happiness

Happiness is a subjective experience that is an ultimate goal for humans. Psychological studies have shown that subjective happiness can be measured reliably and consists of emotional and cognitive components. However, the neural substrates of subjective happiness remain unclear. To investigate this issue, we used structural magnetic resonance imaging and questionnaires that assessed subjective happiness, the intensity of positive and negative emotional experiences, and purpose in life. We found a positive relationship between the subjective happiness score and gray matter volume in the right precuneus. Moreover, the same region showed an association with the combined positive and negative emotional intensity and purpose in life scores. Our findings suggest that the precuneus mediates subjective happiness by integrating the emotional and cognitive components of happiness.

Differences in neural activity when processing emotional arousal and valence in autism spectrum disorders

Individuals with autism spectrum disorders (ASD) often have difficulty recognizing and interpreting facial expressions of emotion, which may impair their ability to navigate and communicate successfully in their social, interpersonal environments. Characterizing specific differences between individuals with ASD and their typically developing (TD) counterparts in the neural activity subserving their experience of emotional faces may provide distinct targets for ASD interventions. Thus we used functional magnetic resonance imaging (fMRI) and a parametric experimental design to identify brain regions in which neural activity correlated with ratings of arousal and valence for a broad range of emotional faces. Participants (51 ASD, 84 TD) were group-matched by age, sex, IQ, race, and socioeconomic status. Using task-related change in blood-oxygen-level-dependent (BOLD) fMRI signal as a measure, and covarying for age, sex, FSIQ, and ADOS scores, we detected significant differences across diagnostic groups in the neural activity subserving the dimension of arousal but not valence. BOLD-signal in TD participants correlated inversely with ratings of arousal in regions associated primarily with attentional functions, whereas BOLD-signal in ASD participants correlated positively with arousal ratings in regions commonly associated with impulse control and default-mode activity. Only minor differences were detected between groups in the BOLD signal correlates of valence ratings. Our findings provide unique insight into the emotional experiences of individuals with ASD. Although behavioral responses to face-stimuli were comparable across diagnostic groups, the corresponding neural activity for our ASD and TD groups differed dramatically. The near absence of group differences for valence correlates and the presence of strong group differences for arousal correlates suggest that individuals with ASD are not atypical in all aspects of emotion-processing. Studying these similarities and differences may help us to understand the origins of divergent interpersonal emotional experience in persons with ASD. Hum Brain Mapp 37:443-461, 2016. © 2015 Wiley Periodicals, Inc.

Dissociation between Emotional Remapping of Fear and Disgust in Alexithymia

There is growing evidence that individuals are able to understand others' emotions because they "embody" them, i.e., re-experience them by activating a representation of the observed emotion within their own body. One way to study emotion embodiment is provided by a multisensory stimulation paradigm called emotional visual remapping of touch (eVRT), in which the degree of embodiment/remapping of emotions is measured as enhanced detection of near-threshold tactile stimuli on one's own face while viewing different emotional facial expressions. Here, we measured remapping of fear and disgust in participants with low (LA) and high (HA) levels of alexithymia, a personality trait characterized by a difficulty in recognizing emotions. The results showed that fear is remapped in LA but not in HA participants, while disgust is remapped in HA but not in LA participants. To investigate the hypothesis that HA might exhibit increased responses to emotional stimuli producing a heightened physical and visceral sensations, i.e., disgust, in a second experiment we investigated participants' interoceptive abilities and the link between interoception and emotional modulations of VRT. The results showed that participants' disgust modulations of VRT correlated with their ability to perceive bodily signals. We suggest that the emotional profile of HA individuals on the eVRT task could be related to their abnormal tendency to be focalized on their internal bodily signals, and to experience emotions in a "physical" way. Finally, we speculated that these results in HA could be due to a enhancement of insular activity during the perception of disgusted faces.

Sensitivity to emotional scene content outside the focus of attention

We investigated whether the emotional content of visual scenes depicting people is processed in peripheral vision. Emotional or neutral scene photographs were paired with a matched scrambled image for 150ms in peripheral vision (≥5°). The pictures were immediately followed by a digit or letter in a discrimination task. Interference (i.e., slowed reaction times) with performance in this task indexed the processing resources drawn by the pictures. Twelve types of specific emotional scene contents (e.g., erotica or mutilation) were compared. Results showed, first, that emotional scenes caused greater interference than neutral scenes, in the absence of fixations. This suggests that emotional scenes are processed and draw covert attention outside the focus of overt attention. Second, interference was similar for female and male participants with pleasant scenes (except for erotica), but females were more affected by all types of unpleasant scenes than males. This reveals that sensitivity to peripheral vision is modulated by sex and affective valence. Third, low-level image properties, visual saliency, and size of bodies and faces, were generally equivalent for emotional and neutral scenes. This rules out the alternative hypothesis of a contribution of non-emotional, purely perceptual factors.

The Unique and Shared Genetic and Environmental Contributions to Fear, Anger, and Sadness in Childhood

This study examined the extent to which subordinate dimensions of negative emotionality were genetically and environmentally distinct in a sample of 1,316 twins (51% female, 85.8% Caucasian, primarily middle class, Mage = 7.87 years, SD = .93), recruited from Wisconsin hospital birth records between 1989 and 2004. Cholesky, independent pathway, and common pathway models were fitted for mother report, father report, and in-home observation of temperament. Although findings support the use of negative emotionality, there were heritable aspects of anger and fear not explained by a common genetic factor, and shared environmental influences common to anger and sadness but not fear. Observed fear was independent from observed anger and sadness. Distinctions support specificity in measurement when considering implications for child development.

A multi-pathway hypothesis for human visual fear signaling

A hypothesis is proposed for five visual fear signaling pathways in humans, based on an analysis of anatomical connectivity from primate studies and human functional connectvity and tractography from brain imaging studies. Earlier work has identified possible subcortical and cortical fear pathways known as the "low road" and "high road," which arrive at the amygdala independently. In addition to a subcortical pathway, we propose four cortical signaling pathways in humans along the visual ventral stream. All four of these traverse through the LGN to the visual cortex (VC) and branching off at the inferior temporal area, with one projection directly to the amygdala; another traversing the orbitofrontal cortex; and two others passing through the parietal and then prefrontal cortex, one excitatory pathway via the ventral-medial area and one regulatory pathway via the ventral-lateral area. These pathways have progressively longer propagation latencies and may have progressively evolved with brain development to take advantage of higher-level processing. Using the anatomical path lengths and latency estimates for each of these five pathways, predictions are made for the relative processing times at selective ROIs and arrival at the amygdala, based on the presentation of a fear-relevant visual stimulus. Partial verification of the temporal dynamics of this hypothesis might be accomplished using experimental MEG analysis. Possible experimental protocols are suggested.

Anger in brain and body: the neural and physiological perturbation of decision-making by emotion

Emotion and cognition are dynamically coupled to bodily arousal: the induction of anger, even unconsciously, can reprioritise neural and physiological resources toward action states that bias cognitive processes. Here we examine behavioural, neural and bodily effects of covert anger processing and its influence on cognition, indexed by lexical decision-making. While recording beat-to-beat blood pressure, the words ANGER or RELAX were presented subliminally just prior to rapid word/non-word reaction-time judgements of letter-strings. Subliminal ANGER primes delayed the time taken to reach rapid lexical decisions, relative to RELAX primes. However, individuals with high trait anger were speeded up by subliminal anger primes. ANGER primes increased systolic blood pressure and the magnitude of this increase predicted reaction time prolongation. Within the brain, ANGER trials evoked an enhancement of activity within dorsal pons and an attenuation of activity within visual occipitotemporal and attentional parietal cortices. Activity within periaqueductal grey matter, occipital and parietal regions increased linearly with evoked blood pressure changes, indicating neural substrates through which covert anger impairs semantic decisions, putatively through its expression as visceral arousal. The behavioural and physiological impact of anger states compromises the efficiency of cognitive processing through action-ready changes in autonomic response that skew regional neural activity.

Brain signatures of perceiving a smile: Time course and source localization

Facial happiness is consistently recognized faster than other expressions of emotion. In this study, to determine when and where in the brain such a recognition advantage develops, EEG activity during an expression categorization task was subjected to temporospatial PCA analysis and LAURA source localizations. Happy, angry, and neutral faces were presented either in whole or bottom-half format (with the mouth region visible). The comparison of part- versus whole-face conditions served to examine the role of the smile. Two neural signatures underlying the happy face advantage emerged. One peaked around 140 ms (left N140) and was source-located at the left IT cortex (MTG), with greater activity for happy versus non-happy faces in both whole and bottom-half face format. This suggests an enhanced perceptual encoding mechanism for salient smiles. The other peaked around 370 ms (P3b and N3) and was located at the right IT (FG) and dorsal cingulate (CC) cortices, with greater activity specifically for bottom-half happy versus non-happy faces. This suggests an enhanced recruitment of face-specific information to categorize (or reconstruct) facial happiness from diagnostic smiling mouths. Additional differential brain responses revealed a specific "anger effect," with greater activity for angry versus non-angry expressions (right N170 and P230; right pSTS and IPL); and a coarse "emotion effect," with greater activity for happy and angry versus neutral expressions (anterior P2 and posterior N170; vmPFC and right IFG).

Common neural correlates of emotion perception in humans

Whether neuroimaging findings support discriminable neural correlates of emotion categories is a longstanding controversy. Two recent meta-analyses arrived at opposite conclusions, with one supporting (Vytal and Hamann []: J Cogn Neurosci 22:2864-2885) and the other opposing this proposition (Lindquist et al. []: Behav Brain Sci 35:121-143). To obtain direct evidence regarding this issue, we compared activations for four emotions within a single fMRI design. Angry, happy, fearful, sad and neutral stimuli were presented as dynamic body expressions. In addition, observers categorized motion morphs between neutral and emotional stimuli in a behavioral experiment to determine their relative sensitivities. Brain-behavior correlations revealed a large brain network that was identical for all four tested emotions. This network consisted predominantly of regions located within the default mode network and the salience network. Despite showing brain-behavior correlations for all emotions, muli-voxel pattern analyses indicated that several nodes of this emotion general network contained information capable of discriminating between individual emotions. However, significant discrimination was not limited to the emotional network, but was also observed in several regions within the action observation network. Taken together, our results favor the position that one common emotional brain network supports the visual processing and discrimination of emotional stimuli.

The pleasures of sad music: a systematic review

Sadness is generally seen as a negative emotion, a response to distressing and adverse situations. In an aesthetic context, however, sadness is often associated with some degree of pleasure, as suggested by the ubiquity and popularity, throughout history, of music, plays, films and paintings with a sad content. Here, we focus on the fact that music regarded as sad is often experienced as pleasurable. Compared to other art forms, music has an exceptional ability to evoke a wide-range of feelings and is especially beguiling when it deals with grief and sorrow. Why is it, then, that while human survival depends on preventing painful experiences, mental pain often turns out to be explicitly sought through music? In this article we consider why and how sad music can become pleasurable. We offer a framework to account for how listening to sad music can lead to positive feelings, contending that this effect hinges on correcting an ongoing homeostatic imbalance. Sadness evoked by music is found pleasurable: (1) when it is perceived as non-threatening; (2) when it is aesthetically pleasing; and (3) when it produces psychological benefits such as mood regulation, and empathic feelings, caused, for example, by recollection of and reflection on past events. We also review neuroimaging studies related to music and emotion and focus on those that deal with sadness. Further exploration of the neural mechanisms through which stimuli that usually produce sadness can induce a positive affective state could help the development of effective therapies for disorders such as depression, in which the ability to experience pleasure is attenuated.

Beyond Emotion: Love as an Encounter of Myth and Drive

Starting with a review of research on love as an emotion, with an emphasis on romantic love, it is argued that despite strong emotional correlates evidence is lacking to conclude that love would meet the criteria of basic emotions. Theoretical developments are proposed where love is conceived of as a combination of an objectless drive, a desire for love, and a mythical and scripted representation that offers the possibility of labeling the current core affect. I argue that the basic motive for love is not so much the partner’s personal attributes, but rather the benefits of the transformative power of being in love.

The neural representation of typical and atypical experiences of negative images: comparing fear, disgust and morbid fascination

Negative stimuli do not only evoke fear or disgust, but can also evoke a state of 'morbid fascination' which is an urge to approach and explore a negative stimulus. In the present neuroimaging study, we applied an innovative method to investigate the neural systems involved in typical and atypical conceptualizations of negative images. Participants received false feedback labeling their mental experience as fear, disgust or morbid fascination. This manipulation was successful; participants judged the false feedback correct for 70% of the trials on average. The neuroimaging results demonstrated differential activity within regions in the 'neural reference space for discrete emotion' depending on the type of feedback. We found robust differences in the ventrolateral prefrontal cortex, the dorsomedial prefrontal cortex and the lateral orbitofrontal cortex comparing morbid fascination to control feedback. More subtle differences in the dorsomedial prefrontal cortex and the lateral orbitofrontal cortex were also found between morbid fascination feedback and the other emotion feedback conditions. This study is the first to forward evidence about the neural representation of the experimentally unexplored state of morbid fascination. In line with a constructionist framework, our findings suggest that neural resources associated with the process of conceptualization contribute to the neural representation of this state.

Determinants of Emotion Duration and Underlying Psychological and Neural Mechanisms

Emotions are traditionally considered to be brief states that last for seconds or a few minutes at most. However, due to pioneering theoretical work of Frijda and recent empirical studies, it has become clear that the duration of emotions is actually highly variable with durations ranging from a few seconds to several hours, or even longer. We review research on determinants of emotion duration. Three classes of determinants are identified: features related to the (a) emotion-eliciting event (event duration and event appraisal), (b) emotion itself (nature of the emotion component, nature of the emotion, and emotion intensity), and (c) emotion-experiencing person (dispositions and emotion regulatory actions). Initial evidence on the psychological and neural mechanisms that underlie their effects is discussed.

The role of the amygdala in the perception of positive emotions: an "intensity detector"

The specific role of the amygdala remains controversial even though the development of functional imaging techniques has established its implication in the emotional process. The aim of this study was to highlight the sensitivity of the amygdala to emotional intensity (arousal). We conducted an analysis of the modulation of amygdala activation according to variation in emotional intensity via an fMRI event-related protocol. Monitoring of electrodermal activity, a marker of psychophysiological emotional perception and a reflection of the activation of the autonomic nervous system, was carried out concurrently. Eighteen subjects (10 men; aged from 22 to 29 years) looked at emotionally positive photographs. We demonstrated that the left and right amygdalae were sensitive to changes in emotional intensity, activating more in response to stimuli with higher intensity. Furthermore, electrodermal responses were more frequent for the most intense stimuli, demonstrating the concomitant activation of the autonomic nervous system. These results highlight the sensitivity of the amygdala to the intensity of positively valenced visual stimuli, and in conjunction with results in the literature on negative emotions, reinforce the role of the amygdala in the perception of intensity.

Cognitive emotion regulation in children: Reappraisal of emotional faces modulates neural source activity in a frontoparietal network

Emotion regulation has an important role in child development and psychopathology. Reappraisal as cognitive regulation technique can be used effectively by children. Moreover, an ERP component known to reflect emotional processing called late positive potential (LPP) can be modulated by children using reappraisal and this modulation is also related to children's emotional adjustment. The present study seeks to elucidate the neural generators of such LPP effects. To this end, children aged 8-14 years reappraised emotional faces, while neural activity in an LPP time window was estimated using magnetoencephalography-based source localization. Additionally, neural activity was correlated with two indexes of emotional adjustment and age. Reappraisal reduced activity in the left dorsolateral prefrontal cortex during down-regulation and enhanced activity in the right parietal cortex during up-regulation. Activity in the visual cortex decreased with increasing age, more adaptive emotion regulation and less anxiety. Results demonstrate that reappraisal changed activity within a frontoparietal network in children. Decreasing activity in the visual cortex with increasing age is suggested to reflect neural maturation. A similar decrease with adaptive emotion regulation and less anxiety implies that better emotional adjustment may be associated with an advance in neural maturation.

Discrete Neural Signatures of Basic Emotions

Categorical models of emotions posit neurally and physiologically distinct human basic emotions. We tested this assumption by using multivariate pattern analysis (MVPA) to classify brain activity patterns of 6 basic emotions (disgust, fear, happiness, sadness, anger, and surprise) in 3 experiments. Emotions were induced with short movies or mental imagery during functional magnetic resonance imaging. MVPA accurately classified emotions induced by both methods, and the classification generalized from one induction condition to another and across individuals. Brain regions contributing most to the classification accuracy included medial and inferior lateral prefrontal cortices, frontal pole, precentral and postcentral gyri, precuneus, and posterior cingulate cortex. Thus, specific neural signatures across these regions hold representations of different emotional states in multimodal fashion, independently of how the emotions are induced. Similarity of subjective experiences between emotions was associated with similarity of neural patterns for the same emotions, suggesting a direct link between activity in these brain regions and the subjective emotional experience.

Functional brain changes underlying irritability in premanifest Huntington's disease

The clinical phenotype of Huntington's disease (HD) consists of motor, cognitive and psychiatric symptoms, of which irritability is an important manifestation. Our aim was to identify the functional and structural brain changes that underlie irritability in premanifest HD (preHD). Twenty preHD carriers and 20 gene-negative controls from HD families took part in the study. Although the 5-year probability of disease onset was only 11%, the preHD group showed striatal atrophy and increased clinical irritability ratings. Functional MRI was performed during a mood induction experiment by means of recollection of emotional (angry, sad, and happy) and neutral autobiographical episodes. While there were no significant group differences in the subjective intensity of the emotional experience, the preHD group showed increased anger-selective activation in a distributed network, including the pulvinar, cingulate cortex, and somatosensory association cortex, compared to gene-negative controls. Pulvinar activation during anger experience correlated negatively with putaminal grey matter volume and positively with irritability ratings in the preHD group. In addition, the preHD group showed a decrease in anger-selective activation in the amygdala, which correlated with putaminal and caudate grey matter volume. In conclusion, compared to gene-negative controls, anger experience in preHD is associated with activity changes in a distributed set of regions known to be involved in emotion regulation. Increased activity is related to behavioral and volumetric measures, providing insight in the pathophysiology of early neuropsychiatric symptoms in preHD.