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.     

Functionally dissociated aspects in anterior and posterior electrocortical processing of facial threat.

The angry facial expression is an important socially threatening stimulus argued to have evolved to regulate social hierarchies. In the present study, event-related potentials (ERP) were used to investigate the involvement and temporal dynamics of the frontal and parietal regions in the processing of angry facial expressions. Angry, happy and neutral faces were shown to eighteen healthy right-handed volunteers in a passive viewing task. Stimulus-locked ERPs were recorded from the frontal and parietal scalp sites. The P200, N300 and early contingent negativity variation (eCNV) components of the electric brain potentials were investigated. Analyses revealed statistical significant reductions in P200 amplitudes for the angry facial expression on both frontal and parietal electrode sites. Furthermore, apart from being strongly associated with the anterior P200, the N300 showed to be more negative for the angry facial expression in the anterior regions also. Finally, the eCNV was more pronounced over the parietal sites for the angry facial expressions. The present study demonstrated specific electrocortical correlates underlying the processing of angry facial expressions in the anterior and posterior brain sectors. The P200 is argued to indicate valence tagging by a fast and early detection mechanism. The lowered N300 with an anterior distribution for the angry facial expressions indicates more elaborate evaluation of stimulus relevance. The fact that the P200 and the N300 are highly correlated suggests that they reflect different stages of the same anterior evaluation mechanism. The more pronounced posterior eCNV suggests sustained attention to socially threatening information.     

Neural systems of threat processing in adolescents: role of pubertal maturation and relation to measures of negative affect

Adolescence ushers in dramatic social and affective changes and increased vulnerability for affective disorders. Yet, little is known about the effects of pubertal maturation on neural systems of social threat processing. We examined adolescents' brain function to social stimuli in relation to pubertal maturation, depressive symptoms, and real-world subjective negative affect. Compared with pre/early adolescents, mid/late adolescents exhibited less amygdala reactivity to emotionally neutral faces relative to non-face stimuli; less ventrolateral prefrontal cortex (VLPFC) reactivity to fearful faces relative to non-face stimuli, neutral faces, or angry faces; and more VLPFC reactivity to angry relative to neutral faces. Amygdala and VLPFC reactivity were correlated with negative affect and depressive symptoms. Threat-processing changes during puberty may facilitate changes in social behavior and negative affect.     

Fearful faces evoke a larger C1 than happy faces in executive attention task: An event-related potential study

Neural responses to negatively valenced stimuli such as fear are enhanced relative to positive or neutral stimuli, reflecting an emotional negativity bias. In the present study, high time resolution event related potential (ERP) techniques were used, to investigate whether C1, the earliest visually evoked potential, is modulated by emotional valence in the executive attention network. Subjects were instructed to respond to the expression of the face, while ignoring the content of word, in an emotional face-word Stroop task. We demonstrated modulation of C1 in response to fearful faces versus happy faces. The differentiation between detection of fearful and happy faces emerged at 60-90ms after the stimulus onset at the posterior electrode sites, and this early differentiation occurred regardless of whether the subject had viewed a congruent or incongruent trials (i.e., happy face with fear label or vice versa). The present results indicate that faces with a fearful expression capture processing resources at an early sensory processing stage.     

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.     

Following the time course of face gender and expression processing: A task-dependent ERP study

The effects of task demands and the interaction between gender and expression in face perception were studied using event-related potentials (ERPs). Participants performed three different tasks with male and female faces that were emotionally inexpressive or that showed happy or angry expressions. In two of the tasks (gender and expression categorization) facial properties were task-relevant while in a third task (symbol discrimination) facial information was irrelevant. Effects of expression were observed on the visual P100 component under all task conditions, suggesting the operation of an automatic process that is not influenced by task demands. The earliest interaction between expression and gender was observed later in the face-sensitive N170 component. This component showed differential modulations by specific combinations of gender and expression (e.g., angry male vs. angry female faces). Main effects of expression and task were observed in a later occipito-temporal component peaking around 230 ms post-stimulus onset (EPN or early posterior negativity). Less positive amplitudes in the presence of angry faces and during performance of the gender and expression tasks were observed. Finally, task demands also modulated a positive component peaking around 400 ms (LPC, or late positive complex) that showed enhanced amplitude for the gender task. The pattern of results obtained here adds new evidence about the sequence of operations involved in face processing and the interaction of facial properties (gender and expression) in response to different task demands.     

Enhanced neural reactivity and selective attention to threat in anxiety

Attentional bias towards threat is implicated in the etiology and maintenance of anxiety disorders. We examined the neural correlates of threat bias in anxious and nonanxious participants to shed light on the neural chronometry of this cognitive bias. In this study, event-related potentials (ERPs) were recorded while anxious (n = 23) and nonanxious (n = 23) young adults performed a probe-discrimination task measuring attentional bias towards threat (angry) and positive (happy) face stimuli. Results showed an attention bias towards threat among anxious participants, but not among nonanxious participants. No bias to positive faces was found. ERP data revealed enhanced C1 amplitude (∼80 ms following threat onset) in anxious relative to nonanxious participants when cue displays contained threat faces. Additionally, P2 amplitude to the faces display was higher in the anxious relative to the nonanxious group regardless of emotion condition (angry/happy/neutral). None of the ERP analyses associated with target processing were significant. In conclusion, our data suggest that a core feature of threat processing in anxiety lies in functional perturbations of a brain circuitry that reacts rapidly and vigorously to threat. It is this over-activation that may set the stage for the attention bias towards threat observed in anxious individuals.     

Activation of the visual cortex in motivated attention

Functional activation (measured with fMRI) in occipital cortex was more extensive when participants view pictures strongly related to primary motive states (i.e., victims of violent death, viewer-directed threat, and erotica). This functional activity was greater than that observed for less intense emotional (i.e., happy families or angry faces) or neutral images (i.e., household objects, neutral faces). Both the extent and strength of functional activity were related to the judged affective arousal of the different picture contents, and the same pattern of functional activation was present whether pictures were presented in color or in grayscale. It is suggested that more extensive visual system activation reflects "motivated attention," in which appetitive or defensive motivational engagement directs attention and facilitates perceptual processing of survival-relevant stimuli.     

The effects of cortisol administration on approach-avoidance behavior: an event-related potential study

We investigated the effects of cortisol administration (50 mg) on approach and avoidance tendencies in low and high trait avoidant healthy young men. Event-related brain potentials (ERPs) were measured during a reaction time task, in which participants evaluated the emotional expression of photographs of happy and angry faces by making an approaching (flexion) or avoiding (extension) arm movement. The task consisted of an affect-congruent (approach happy faces and avoid angry faces) and an affect-incongruent (reversed instruction) condition. Behavioral and ERP analyses showed that cortisol enhanced congruency effects for angry faces in highly avoidant individuals only. The ERP effects involved an increase of both early (P150) and late (P3) positive amplitudes, indicative of increased processing of the angry faces in high avoidant subjects after cortisol administration. Together, these results suggest a context-specific effect of cortisol on processing of, and adaptive responses to, motivationally significant threat stimuli, particularly in participants highly sensitive to threat signals.     

The effects of cortisol administration on approach–avoidance behavior: An event-related potential study

We investigated the effects of cortisol administration (50 mg) on approach and avoidance tendencies in low and high trait avoidant healthy young men. Event-related brain potentials (ERPs) were measured during a reaction time task, in which participants evaluated the emotional expression of photographs of happy and angry faces by making an approaching (flexion) or avoiding (extension) arm movement. The task consisted of an affect-congruent (approach happy faces and avoid angry faces) and an affect-incongruent (reversed instruction) condition. Behavioral and ERP analyses showed that cortisol enhanced congruency effects for angry faces in highly avoidant individuals only. The ERP effects involved an increase of both early (P150) and late (P3) positive amplitudes, indicative of increased processing of the angry faces in high avoidant subjects after cortisol administration. Together, these results suggest a context-specific effect of cortisol on processing of, and adaptive responses to, motivationally significant threat stimuli, particularly in participants highly sensitive to threat signals.     

Nonspatial intermodal selective attention is mediated by sensory brain areas: evidence from event-related potentials

The present study focuses on the question of whether inter- and intramodal forms of attention are reflected in activation of the same or different brain areas. ERPs were recorded while subjects were presented a random sequence of visual and auditory stimuli. They were instructed to attend to nonspatial attributes of either auditory or visual stimuli and to detect occasional target stimuli within the attended channel. An occipital selection negativity was found for intramodal attention to visual stimuli. Visual intermodal attention was also manifested in a similar negativity. A symmetrical dipole pair in the medial inferior occipital areas could account for the intramodal effects. Dipole pairs for the intermodal attention effect had a slightly more posterior location compared to the dipole pair for the intramodal effect. Auditory intermodal attention was manifested in an early enhanced negativity overlapping with the N1 and P2 components, which was localized using a symmetrical dipole pair in the lateral auditory cortex. The onset of the intramodal attention effect was somewhat later (around 200 ms), and was reflected in a frontal processing negativity. The present results indicate that intra- and intermodal forms of attention were indeed similar for visual stimuli. Auditory data suggest the involvement of multiple brain areas.     

Virtual friend or threat? The effects of facial expression and gaze interaction on psychophysiological responses and emotional experience

The present study aimed to investigate the impact of facial expression, gaze interaction, and gender on attention allocation, physiological arousal, facial muscle responses, and emotional experience in simulated social interactions. Participants viewed animated virtual characters varying in terms of gender, gaze interaction, and facial expression. We recorded facial EMG, fixation duration, pupil size, and subjective experience. Subject's rapid facial reactions (RFRs) differentiated more clearly between the character's happy and angry expression in the condition of mutual eye-to-eye contact. This finding provides evidence for the idea that RFRs are not simply motor responses, but part of an emotional reaction. Eye movement data showed that fixations were longer in response to both angry and neutral faces than to happy faces, thereby suggesting that attention is preferentially allocated to cues indicating potential threat during social interaction.     

Effects of anxiety on the processing of fearful and happy faces: an event-related potential study

This study investigated the influence of trait anxiety on event-related potentials (ERPs) to fearful, happy, and neutral faces. Fearful faces, relative to neutral, elicited a range of effects in the low-trait anxiety (LTA) group: an enhanced visual P1 component, an early posterior negativity (EPN), and a sustained fronto-central positivity. Emotional expression effects were generally weaker for happy faces. The enhanced fronto-central positivity and EPN triggered by fearful stimuli in LTA participants were less pronounced in the high-trait anxiety (HTA) group, while the enhancement of the visual P1 seen in the LTA group was further augmented in the HTA group. This represents a clear dissociation across anxiety groups between rapid attentional processing as reflected by the visual P1 and later strategic processing as reflected by fronto-central and EPN components. These effects of high-trait anxiety in potentiating initial threat evaluation but attenuating later cognitive processing are discussed in the context of the possible roles of neural systems underlying threat evaluation, cognitive avoidance, and differentiated affective responses.     

You don’t like me,do you? Enhanced ERP responses to averted eye gaze in social anxiety

Social anxiety is associated with an attentional bias toward angry and fearful faces, along with an enhanced processing of faces per se. However, little is known about the processing of gaze direction, a subtle but important social cue. Participants with high or low social anxiety (HSA/LSA) observed eye pairs with direct or averted gaze while subjective ratings and event-related potentials (ERPs) were measured. Behaviorally, all participants rated averted gaze as more unpleasant than direct gaze. Neurally, only HSA participants showed a trend for higher P100 amplitudes to averted gaze and significantly enhanced processing at late latencies (Late positive potential [LPP]), indicative of a specific processing bias for averted gaze. Furthermore, HSA individuals showed enhanced processing of both direct and averted gaze relative to the LSA group at intermediate latencies (Early posterior negativity [EPN]). Both general and specific attentional biases play a role in social anxiety. Averted gaze - a potential sign of disinterest - deserves more attention in the attentional bias literature.     

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.     

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.     

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.     

Threat‐conditioned contexts modulate the late positive potential to faces—A mobile EEG/virtual reality study

In everyday life, the motivational value of faces is bound to the contexts in which faces are perceived. Electrophysiological studies have demonstrated that inherent negatively valent contexts modulate cortical face processing as assessed with ERP components. However, it is not well understood whether learned (rather than inherent) and three‐dimensional aversive contexts similarly modulate the neural processing of faces. Using full immersive virtual reality (VR) and mobile EEG techniques, 25 participants underwent a differential fear conditioning paradigm, in which one virtual room was paired with an aversive noise burst (threat context) and another with a nonaversive noise burst (safe context). Subsequently, avatars with neutral or angry facial expressions were presented in the threat and safe contexts while EEG was recorded. Analysis of the late positive potential (LPP), which presumably indicates motivational salience, revealed a significant interaction of context (threat vs. safe) and face type (neutral vs. angry). Neutral faces evoked increased LPP amplitudes in threat versus safe contexts, while angry faces evoked increased early LPP amplitudes regardless of context. In addition to indicating that threat‐conditioned contexts alter the processing of ambiguous faces, the present study demonstrates the successful integration of EEG and VR with particular relevance for affective neuroscience research.     

Threat sensitivity as assessed by automatic amygdala response to fearful faces predicts speed of visual search for facial expression

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.     

Relationship between trait anxiety, prefrontal cortex, and attention bias to angry faces in children and adolescents

Using event-related functional magnetic resonance imaging (fMRI) with a visual-probe task that assesses attention to threat, we investigated the cognitive and neurophysiological correlates of trait anxiety in youth. During fMRI acquisition, 16 healthy children and adolescents viewed angry-neutral face pairs and responded to a probe that was on the same (angry-congruent) or opposite (angry-incongruent) side as the angry face. Attention bias scores were calculated by subtracting participants' mean reaction time for angry-congruent trials from angry-incongruent trials. Trait anxiety was positively associated with attention bias towards angry faces. Neurophysiologically, trait anxiety was positively associated with right dorsolateral prefrontal cortex (PFC) activation on a contrast of trials that reflect the attention bias for angry faces (i.e. angry-incongruent versus angry-congruent trials). Trait anxiety was also positively associated with right ventrolateral PFC activation on trials with face stimuli (vesus baseline), irrespective of their emotional content.