Don't look at me in anger! Enhanced processing of angry faces in anticipation of public speaking

Anxiety is supposed to enhance the processing of threatening information. Here, we investigated the cortical processing of angry faces during anticipated public speaking. To elicit anxiety, a group of participants was told that they would have to perform a public speech. As a control condition, another group was told that they would have to write a short essay. During anticipation of these tasks, participants saw facial expressions (angry, happy, and neutral) while electroencephalogram was recorded. Event‐related potential analysis revealed larger N170 amplitudes for angry compared to happy and neutral faces in the anxiety group. The early posterior negativity as an index of motivated attention was also enhanced for angry compared to happy and neutral faces in participants anticipating public speaking. These results indicate that fear of public speaking influences early perceptual processing of faces such that especially the processing of angry faces is facilitated.     

Are two threats worse than one? The effects of face race and emotional expression on fear conditioning

Facial cues of racial outgroup or anger mediate fear learning that is resistant to extinction. Whether this resistance is potentiated if fear is conditioned to angry, other race faces has not been established. Two groups of Caucasian participants were conditioned with two happy and two angry face conditional stimuli (CSs). During acquisition, one happy and one angry face were paired with an aversive unconditional stimulus whereas the second happy and angry faces were presented alone. CS face race (Caucasian, African American) was varied between groups. During habituation, electrodermal responses were larger to angry faces regardless of race and declined less to other race faces. Extinction was immediate for Caucasian happy faces, delayed for angry faces regardless of race, and slowest for happy racial outgroup faces. Combining the facial cues of other race and anger does not enhance resistance to extinction of fear.     

Enhanced Early Posterior Negativity to Fearful Faces in Patients with Anxiety Disorder

Patients with anxiety disorders (AnDs) have distinct patterns of threat-related emotional processing compared to healthy controls (HCs). The current study investigated the temporal course of emotional processing in AnDs by examining Event-related potential (ERP) components. Twenty-three AnDs and twenty-four age- and gender-matched HCs viewed emotional (fearful, happy) and neutral faces while their electroencephalograms were recorded. Early (P100, N170), middle (early posterior negativity; EPN), and late ERP components late positive potential were analyzed. To localize ERP source activity, standardized low-resolution brain electromagnetic tomography (sLORETA) was used. AnDs displayed significantly enhanced mean amplitude of the EPN compared to HCs when fearful faces were presented. In addition, the EPN’s mean amplitude elicited by fearful faces was more pronounced than for happy and neutral faces in AnDs, whereas in HCs the EPN elicited by fearful faces was only augmented compared to neutral faces. Finally, sLORETA analysis revealed that the source activity of the EPN (fearful minus happy face condition) was increased in the cuneus and precuneus in AnDs compared to HCs. Our results indicate that the EPN is a distinct ERP component modulated by facial emotional processing in AnDs. Furthermore, the results show that anxiety symptoms enhance selective attention for fearful faces. Finally, it revealed that the cuneus and precuneus are involved in fearful face processing in AnDs.     

Event-related delta and theta synchronization during explicit and implicit emotion processing

Emotion information processing may occur in two modes which are differently represented in conscious awareness. Fast online processing involves coarse-grained analysis of salient features, and is not represented in conscious awareness; offline processing takes hundreds of milliseconds to generate fine-grained analysis, and is represented in conscious awareness. These processing modes may be studied using event-related electroencephalogram theta and delta synchronization as a marker of emotion processing. Two experiments were conducted, which differed on the mode of emotional information presentation. In the explicit mode subjects were explicitly instructed to evaluate the emotional content of presented stimuli; in the implicit mode they performed a gender discrimination task. Firstly, we show that in both experiments theta and delta synchronization is stronger upon presentation of “emotional” than “neutral” stimuli, and in subjects who are more sensitive, or experience higher emotional involvement than in less sensitive or detached subjects. Secondly, we show that in the implicit mode theta and delta synchronization is more pronounced in an early (before 250 ms post-stimulus) processing stage, whereas in the explicit mode it is more pronounced in a later processing stage. Source localization analysis showed that implicit processing of angry and happy (relative to neutral) faces is associated with higher early (before 250 ms) theta synchronization in the right parietal cortex and the right insula, respectively. Explicit processing of angry and happy faces is associated with higher late (after 250 ms) theta synchronization in the left temporal lobe and bilateral prefrontal cortex, respectively.     

On the resistance to extinction of fear conditioned to angry faces

The present study investigated whether, like fear conditioned to pictures of snakes and spiders, fear conditioned to angry faces resists extinction even after verbal instruction and removal of the shock electrode. Participants were trained in a differential Pavlovian fear conditioning procedure with angry face or happy face conditional stimuli (CSs). Prior to extinction, half the participants in each group were informed that no more unconditional stimuli would be presented and the shock electrode was removed. In the absence of this manipulation, participants showed resistance to extinction after training with angry face CSs, but not after training with happy face CSs. Instructed extinction and electrode removal abolished fear conditioning regardless of the emotion expressed by the CS faces. This finding suggests that fear conditioned to angry faces, like fear conditioned to racial out-group faces, is more malleable than fear conditioned to snakes and spiders.     

海洛因戒断者情绪识别时面孔和声音刺激的整合

目的:考察海洛因戒断者视听情绪一致和不一致条件下的情绪识别表现,研究其情绪面孔和声音刺激的整合加工特点。方法:选取男性海洛因戒断者32例(戒断组)和健康男性30例(对照组),采用视听情绪分类任务,要求被试忽略情绪声音而对情绪面孔的类型(愤怒、快乐)做出判断。结果:戒断组在一致条件下的反应时低于不一致[(670±66)ms vs.(687±77)ms,P<0.001];戒断组不一致条件与一致条件的反应时差值低于对照组[(32±31)ms vs.(17±21)ms,P<0.05];在愤怒声音下,对照组对愤怒面孔的反应时低于快乐面孔[(653±94)ms vs.(679±78)ms,P<0.05],而戒断组对两种面孔的反应时差异无统计学意义(P>0.05)。结论:海洛因戒断者表现出了情绪多通道整合促进效应,但其多通道整合加工能力弱于正常人;戒断者多通道整合受损可能体现在对愤怒声音不敏感。     

Shifting the focus of attention modulates amygdala and anterior cingulate cortex reactivity to emotional faces

Functional neuroimaging studies have largely established the prominence of amygdala during emotion processing and prefrontal areas such as anterior cingulate cortex (ACC) during attentional modulation. In general, emotion processing paradigms known to probe amygdala have not been adapted to recruit prefrontal areas. In this study we used a well-known perceptual face matching paradigm, designed to elicit amygdala response, and asked volunteers to shift their focus in order to recruit regions responsible for attentional control. Stimuli comprised a trio of geometric shapes (circles, rectangles, triangles) presented alongside a trio of emotional faces (angry, fear, or happy) within the same field of view, and subjects were instructed to Match Faces or Match Shapes, as a means of attending to and away from the emotional content, respectively. We observed greater amygdala reactivity to Match Faces (>Match Shapes), and greater rostral ACC response to Match Shapes (>Match Faces). Results indicate that simply and volitionally directing attention toward or away from emotional content correspondingly modulates amygdala and ACC activity.     

Convergence of fMRI and ERP measures of emotional face processing in combat‐exposed U. S. military veterans

The late positive potential (LPP) and fMRI blood‐oxygen‐level dependent (BOLD) activity can provide complementary measures of the processing of affective and social stimuli. Separate lines of research using these measures have often employed the same stimuli, paradigms, and samples; however, there remains relatively little understanding of the way in which individual differences in one of these measures relates to the other, and all prior research has been conducted in psychiatrically healthy samples and using emotional scenes (not faces). Here, 32 combat‐exposed U. S. military veterans with varying levels of posttraumatic stress symptomatology viewed affective social stimuli (angry, fearful, and happy faces) and geometric shapes during separate EEG and fMRI BOLD recordings. Temporospatial principal component analysis was used to quantify the face‐elicited LPP in a data‐driven manner, prior to conducting whole‐brain correlations between resulting positivities and fMRI BOLD elicited by faces. Participants with larger positivities to fearful faces (> shapes) showed increased activation in the amygdala; larger positivities to angry and happy faces (> shapes) were associated with increased BOLD activation in the posterior fusiform gyrus and inferior temporal gyrus, respectively. Across all face types, larger positivities were associated with increased activation in the fusiform “face” area. Correlations using mean area amplitude LPPs showed an association with increased activation in the anterior insula for angry faces (> shapes). LPP‐BOLD associations were not moderated by PTSD. Findings provide the first evidence of correspondence between face‐elicited LPP and BOLD activation across a range of (normal to disordered) psychiatric health.     

Emotion in motion: Facial dynamics affect infants' neural processing of emotions

Research investigating the early development of emotional processing has focused mainly on infants' perception of static facial emotional expressions, likely restricting the amount and type of information available to infants. In particular, the question of whether dynamic information in emotional facial expressions modulates infants' neural responses has been rarely investigated. The present study aimed to fill this gap by recording 7-month-olds' event-related potentials to static (Study 1) and dynamic (Study 2) happy, angry, and neutral faces. In Study 1, happy faces evoked a faster right-lateralized negative central (Nc) component compared to angry faces. In Study 2, both happy and angry faces elicited a larger right-lateralized Nc compared to neutral faces. Irrespective of stimulus dynamicity, a larger P400 to angry faces was associated with higher scores on the Negative Affect temperamental dimension. Overall, results suggest that 7-month-olds are sensitive to facial dynamics, which might play a role in shaping the neural processing of facial emotional expressions. Results also suggest that the amount of attentional resources infants allocate to angry expressions is associated to their temperamental traits. These findings represent a promising avenue for future studies exploring the neurobiological processes involved in perceiving emotional expressions using dynamic stimuli.     

Examining Socioaffective Processing Biases in Cigarette Smokers with High Versus Low Trait Hostility

Developing measures of socioaffective processing is important for understanding the mechanisms underlying emotional-interpersonal traits relevant to health, such as hostility. In this study, cigarette smokers with low (LH; n = 49) and high (HH; n = 43) trait hostility completed the Emotional Interference Gender Identification Task (EIGIT), a newly developed behavioral measure of socioaffective processing biases toward facial affect. The EIGIT involves quickly categorizing the gender of facial pictures that vary in affective valence (angry, happy, neutral, sad). Results showed that participants were slower and less accurate in categorizing the gender of angry faces in comparison to happy, neutral, and sad faces (which did not differ), signifying interference indicative of a socioaffective processing bias toward angry faces. Compared to LH individuals, HH participants exhibited diminished biases toward angry faces on error-based (but not speed-based) measures of emotional interference, suggesting impaired socioaffective processing. The EIGIT may be useful for future research on the role of socioaffective processing in traits linked with poor health.     

Electrocortical processing of social signals of threat in combat-related post-traumatic stress disorder

Post-traumatic stress disorder (PTSD) is characterized by avoidance, emotional numbing, increased arousal and hypervigilance for threat following a trauma. Thirty-three veterans (19 with PTSD, 14 without PTSD) who had experienced combat trauma while on deployment in Iraq and/or Afghanistan completed an emotional faces matching task while electroencephalography was recorded. Vertex positive potentials (VPPs) elicited by happy, angry and fearful faces were smaller in veterans with versus without PTSD. In addition, veterans with PTSD exhibited smaller late positive potentials (LPPs) to angry faces and greater intrusive symptoms predicted smaller LPPs to fearful faces in the PTSD group. Veterans with PTSD were also less accurate at identifying angry faces, and accuracy decreased in the PTSD group as hyperarousal symptoms increased. These findings show reduced early processing of emotional faces, irrespective of valence, and blunted prolonged processing of social signals of threat in conjunction with impaired perception for angry faces in PTSD.     

Signatures of emotional face processing measured by event-related potentials in 7-month-old infants

The ability to distinguish facial emotions emerges in infancy. Although this ability has been shown to emerge between 5 and 7 months of age, the literature is less clear regarding the extent to which neural correlates of perception and attention play a role in processing of specific emotions. This study's main goal was to examine this question among infants. To this end, we presented angry, fearful, and happy faces to 7-month-old infants (N = 107, 51% female) while recording event-related brain potentials. The perceptual N290 component showed a heightened response for fearful and happy relative to angry faces. Attentional processing, indexed by the P400, showed some evidence of a heightened response for fearful relative to happy and angry faces. We did not observe robust differences by emotion in the negative central (Nc) component, although trends were consistent with previous work suggesting a heightened response to negatively valenced expressions. Results suggest that perceptual (N290) and attentional (P400) processing is sensitive to emotions in faces, but these processes do not provide evidence for a fear-specific bias across components.     

Automatic emotion regulation in response inhibition: The temporal dynamics of emotion counter‐regulation during a go/no‐go task

Recent behavioral studies indicate that emotion counter‐regulation automatically allocates attention to events that are opposite in the valence to the experienced emotional state. The present study explored the effect of emotion counter‐regulation on response inhibition by using ERPs in a go/no‐go paradigm. We recruited 58 subjects and randomly assigned them to either the angry priming group (watching Nanjing Massacre movie clips) or the neutral priming group (watching “mending a computer” movie clips). The behavioral results revealed that participants in the angry priming group responded significantly more accurately to go happy and no‐go angry faces than go angry and no‐go happy faces. The analyses of ERPs revealed that the amplitudes of the no‐go N2 and no‐go P3 were significantly larger for the happy faces than for the angry faces in the angry priming group. However, no such effects were found in the neutral priming group. These results suggest that highly aroused angry emotion could prompt a priority response to happy emotion stimuli and restrict the responses to angry emotion stimuli through emotion counter‐regulation.     

Current status of the anger superiority hypothesis: A meta‐analytic review of N2pc studies

Numerous investigators have tested contentions that angry faces capture early attention more completely than happy faces do in the context of other faces. However, syntheses of studies on early event‐related potentials related to the anger superiority hypothesis have yet to be conducted, particularly in relation to the N200 posterior‐contralateral (N2pc) component which provides a reliable electrophysiological index related to orienting of attention suitable for testing this hypothesis. Fifteen samples (N = 534) from 13 studies featuring the assessment of N2pc amplitudes during exposure to angry‐neutral and/or happy‐neutral facial expression arrays were included for meta‐analysis. Moderating effects of study design features and sample characteristics on effect size variability were also assessed. N2pc amplitudes elicited by affectively valenced expressions (angry and happy) were significantly more pronounced than those elicited by neutral expressions. However, the mean effect size difference between angry and happy expressions was ns. N2pc effect sizes were moderated by sample age, number of trials, and nature of facial images used (schematic vs. real) with larger effect sizes observed when samples were comparatively younger, more task trials were presented and schematic face arrays were used. N2pc results did not support anger superiority hypothesis. Instead, attentional resources allocated to angry versus happy facial expressions were similar in early stages of processing. As such, possible adaptive advantages of biases in orienting toward both anger and happy expressions warrant consideration in revisions of related theory.     

PTSD and its dissociative subtype through the lens of the insula: Anterior and posterior insula resting-state functional connectivity and its predictive validity using machine learning

Individuals with post-traumatic stress disorder (PTSD) typically experience states of reliving and hypervigilance; however, the dissociative subtype of PTSD (PTSD+DS) presents with additional symptoms of depersonalization and derealization. Although the insula is critical to emotion processing, its association with these contrasting symptom profiles is yet to be fully delineated. Accordingly, we investigated insula subregion resting-state functional connectivity patterns among individuals with PTSD, PTSD+DS, and healthy controls. Using SPM12 and PRONTO software, we implemented a seed-based resting-state functional connectivity approach, along with multiclass Gaussian process classification machine learning, respectively, in order to evaluate unique patterns and the predictive validity of insula subregion connectivity among individuals with PTSD (n = 84), PTSD+DS (n = 49), and age-matched healthy controls (n = 51). As compared to PTSD and PTSD+DS, healthy controls showed increased right anterior and posterior insula connectivity with frontal lobe structures. By contrast, PTSD showed increased bilateral posterior insula connectivity with subcortical structures, including the periaqueductal gray. Strikingly, as compared to PTSD and controls, PTSD+DS showed increased bilateral anterior and posterior insula connectivity with posterior cortices, including the left lingual gyrus and the left precuneus. Moreover, machine learning analyses were able to classify PTSD, PTSD+DS, and controls using insula subregion connectivity patterns with 80.4% balanced accuracy (p < .01). These findings suggest a neurobiological distinction between PTSD and its dissociative subtype with regard to insula subregion functional connectivity patterns. Furthermore, machine learning algorithms were able to utilize insula resting-state connectivity patterns to discriminate between participant groups with high predictive accuracy.     

Dissociative responses to conscious and non-conscious fear impact underlying brain function in post-traumatic stress disorder

BACKGROUND: Dissociative reactions in post-traumatic stress disorder (PTSD) have been regarded as strategic responses that limit arousal. Neuroimaging studies suggest distinct prefrontal responses in individuals displaying dissociative and hyperarousal responses to threat in PTSD. Increased prefrontal activity may reflect enhanced regulation of limbic arousal networks in dissociation. If dissociation is a higher-order regulatory response to threat, there may be differential responses to conscious and automatic processing of threat stimuli. This study addresses this question by examining the impact of dissociation on fear processing at different levels of awareness. METHOD: Functional magnetic resonance imaging (fMRI) with a 1.5-T scanner was used to examine activation to fearful (versus neutral) facial expressions during consciously attended and non-conscious (using backward masking) conditions in 23 individuals with PTSD. Activation in 11 individuals displaying non-dissociative reactions was compared to activation in 12 displaying dissociative reactions to consciously and non-consciously perceived fear stimuli. RESULTS: Dissociative PTSD was associated with enhanced activation in the ventral prefrontal cortex for conscious fear, and in the bilateral amygdala, insula and left thalamus for non-conscious fear compared to non-dissociative PTSD. Comparatively reduced activation in the dissociative group was apparent in dorsomedial prefrontal regions for conscious fear faces. CONCLUSIONS: These findings confirm our hypotheses of enhanced prefrontal activity to conscious fear and enhanced activity in limbic networks to non-conscious fear in dissociative PTSD. This supports the theory that dissociation is a regulatory strategy invoked to cope with extreme arousal in PTSD, but this strategy appears to function only during conscious processing of threat.     

An event-related potential study of the processing of affective facial expressions in young children who experienced maltreatment during the first year of life

This investigation examined the effects of maltreatment during the first year of life on the neural correlates of processing facial expressions of emotion at 30 months of age. Event-related potentials (ERPs) in response to children passively viewing standardized pictures of female models posing angry, happy, and neutral facial expressions were examined. Four ERP waveform components were derived: early negative (N150), early positive (P260), negative central (Nc), and positive slow wave (PSW). Differences in these waveforms between a group of 35 maltreated and 24 nonmaltreated children were reported. The groups did not differ on the early perceptual negative component (N150), whereas the maltreated children had greater P260 amplitude at frontal leads compared to the nonmaltreated children in response to viewing angry facial expressions. For the Nc component, the nonmaltreated comparison children exhibited greater amplitude while viewing pictures of happy faces compared to angry and neutral faces, whereas the maltreated children showed greater Nc amplitude at central sites while viewing angry faces. For the PSW, the nonmaltreated group showed a greater area score in the right hemisphere in response to viewing angry facial expressions compared to the maltreated group. The results are discussed in terms of brain development and function, as well as their implications for the design and evaluation of preventive interventions.     

Cortisol-induced enhancement of emotional face processing in social phobia depends on symptom severity and motivational context

We investigated the effects of cortisol administration on approach and avoidance tendencies in 20 patients with social anxiety disorder (SAD). Event-related brain potentials (ERPs) were measured during a reaction time task, in which patients evaluated the emotional expression of photographs of happy and angry faces by making an approaching (flexion) or avoiding (extension) arm movement. Patients showed significant avoidance tendencies for angry but not for happy faces, both in the placebo and cortisol condition. Moreover, ERP analyses showed a significant interaction of condition by severity of social anxiety on early positive (P150) amplitudes during avoidance compared to approach, indicating that cortisol increases early processing of social stimuli (in particular angry faces) during avoidance. This result replicates previous findings from a non-clinical sample of high anxious individuals and demonstrates their relevance for clinical SAD. Apparently the cortisol-induced increase in processing of angry faces in SAD depends on symptom severity and motivational context.     

Functional and effective connectivity of anterior insula in anorexia nervosa and bulimia nervosa

The anterior insula has been proposed to play a crucial role in eating disorders. However, it is still poorly understood how the anterior insula is involved in anorexia nervosa (AN) and bulimia nervosa (BN), which are characterized by opposite motivational responses to food. We applied a cue-reactivity paradigm using blood oxygen level-dependent functional magnetic resonance imaging in women with AN (N=18) and BN (N=20) and age-matched healthy controls (N=20). We defined the left anterior insula as a region-of-interest and performed seed-based functional connectivity and effective connectivity MRI analysis. In response to food images compared to non-food images, both the AN group and BN group demonstrated increased activity in the left anterior insula. In the AN group, the left anterior insula demonstrated significant interactions with the right insula and right inferior frontal gyrus. In the BN group, the left anterior insula demonstrated significant interactions with the medial orbitofrontal cortex. The distinct patterns of functional and effective connectivity of the anterior insula may contribute to the different clinical features of AN and BN.     

Selective attention to threatening faces in delusion‐prone individuals

Introduction. Selective attention to threat‐related information has been associated with clinical delusions in schizophrenia and nonclinical delusional ideation in healthy individuals. However, it is unclear whether biased attention for threat reflects early engagement effects on selective attention, or later difficulties in disengaging attention from perceived threat. The present study examined which of these processes operate in nonclinical delusion‐prone individuals.

Methods. A total of 100 psychologically healthy participants completed the Peters et al. () Delusions Inventory (PDI). Twenty‐two scoring in the upper quartile (high‐PDI group) and 22 scoring in the lower quartile (low‐PDI group) completed a modified dot‐probe task. Participants detected dot‐probes appearing 200, 500, or 1250 ms after an angry‐neutral face pair or a happy‐neutral face pair.

Results. High‐PDI individuals responded faster to dot‐probes presented in the same location as angry compared to happy faces at the short 200 ms stimulus onset asynchrony (SOA), but only when the emotional faces were presented to the left visual field. At the two longer SOAs (500 ms, 1250 ms), the high‐PDI group were also faster to respond to dot‐probes presented in the same location as angry compared to happy faces and slower to respond to dot‐probes presented in different spatial locations to angry (vs. happy) faces. The latter effects were seen whether emotional faces were presented to the left or the right visual field.

Conclusions. Results support the operation of emotion‐selective engagement and defective disengagement for threat‐related facial expressions (i.e., anger) in delusion‐prone individuals.