Interaction of facial expressions and familiarity: ERP evidence

The respiratory behavior during affective states is not completely understood. We studied breathing pattern responses to picture series in 37 participants. We also measured end-tidal pCO₂ (EtCO₂) to determine if ventilation is in balance with metabolic demands and spontaneous eye-blinking to investigate the link between respiration and attention.

Minute ventilation (MV) and inspiratory drive increased with self-rated arousal. These relationships reflected increases in inspiratory volume rather than shortening of the time parameters. EtCO₂ covaried with pleasantness but not arousal. Eye-blink rate decreased with increasing unpleasantness in line with a negativity bias in attention.

This study confirms that respiratory responses to affective stimuli are organized to a certain degree along the dimensions of valence and arousal. It shows, for the first time, that during picture viewing, ventilatory increases with increasing arousal are in balance with metabolic activity and that inspiratory volume is modulated by arousal. MV emerges as the most reliable respiratory index of self-perceived arousal.     

Positive emotion speeds up conflict processing: ERP responses in an auditory Simon task

Emotions signal the particular relevance of situations, threatening or rewarding, and influence perception and behaviour accordingly. Research to date has predominantly investigated the impact of negative emotional stimuli. However, rapid reactions to positive emotional stimuli are similarly adaptive. Here, we tested the influence of positive emotional stimuli on attentional control, which enables reacting to conflicting stimulation. We therefore presented positive emotional and neutral words in an auditory Simon task. Reaction times revealed faster resolution of conflict when target stimuli were positive compared to neutral words. Also, emotion modulated the first conflict-sensitive event-related brain potential, a negativity at 420 ms, indicating an influence on early stages of conflict processing. These results complement recent data on negative stimuli and suggest that positive stimuli are equally salient. The rapid impact on attentional control is evolutionary highly adaptive as it reduces the time that conflict yields an organism incapable of responding to reward-signalling stimuli.     

Effects of reward context on feedback processing as indexed by time‐frequency analysis

The role of reward context has been investigated as an important factor in feedback processing. Previous work has demonstrated that the amplitude of the feedback negativity (FN) depends on the value of the outcome relative to the range of possible outcomes in a given context, not the objective value of the outcome. However, some research has shown that the FN does not scale with loss magnitude in loss‐only contexts, suggesting that some contexts do not show a pattern of context dependence. Methodologically, time‐frequency decomposition techniques have proven useful for isolating time‐domain ERP activity as separable processes indexed in delta (< 3 Hz) and theta (3–7 Hz). Thus, the current study assessed the role of context in a modified gambling feedback task using time‐frequency analysis to better isolate the underlying processes. Results revealed that theta was more context dependent and reflected a binary evaluation of bad versus good outcomes in the gain and even contexts. Delta was more context independent: good outcomes scaled linearly with reward magnitude and good‐bad differences scaled with context valence. Our findings reveal that theta and delta are differentially sensitive to context and that context valence may play a critical role in determining how the brain processes feedback.     

The influence of stimulus valence on perceptual processing of facial expressions and subsequent response inhibition

The constant interplay between affective processing and cognitive control supports emotion regulation and appropriate social functioning. Even when affective stimuli are processed implicitly, threat-related stimuli are prioritized in the earliest stages of processing; yet, it remains unclear how implicit attention to affect influences subsequent cognitive control functions. The present study evaluated the influence of affective valence on early perceptual processes and subsequent response inhibition in a context where affective properties of the stimuli (facial expressions) were not critical for performing the task. Participants (N = 32) completed an affective stop-signal task (SST) while their scalp EEGs were recorded. The SST assessed response inhibition while participants implicitly attended to happy and afraid facial expressions that were matched for level of arousal. Behavioral performance was measured via response time and accuracy while physiological response was measured via the P100, N170, and N200/P300 ERP components. Decreased gender discrimination accuracy, delayed P100 latency, and more negative N170 amplitude were observed for afraid faces compared to happy faces, suggesting a shift in processing with respect to face valence. However, differences in stopping accuracy or N200/P300 ERP components during response inhibition were not observed, pointing to top-down cognitive processes likely being recruited to override the early automatic response to prioritize threat-related stimuli. Findings highlight that, in this implicit affective attention task, threat-related stimuli are prioritized early during processing, but implicitly attending to differentially valenced stimuli did not modulate subsequent cognitive control functions.     

The effect of emotionally valenced eye region images on visuocortical processing of surprised faces

In this study, we presented pictorial representations of happy, neutral, and fearful expressions projected in the eye regions to determine whether the eye region alone is sufficient to produce a context effect. Participants were asked to judge the valence of surprised faces that had been preceded by a picture of an eye region. Behavioral results showed that affective ratings of surprised faces were context dependent. Prime‐related ERPs with presentation of happy eyes elicited a larger P1 than those for neutral and fearful eyes, likely due to the recognition advantage provided by a happy expression. Target‐related ERPs showed that surprised faces in the context of fearful and happy eyes elicited dramatically larger C1 than those in the neutral context, which reflected the modulation by predictions during the earliest stages of face processing. There were larger N170 with neutral and fearful eye contexts compared to the happy context, suggesting faces were being integrated with contextual threat information. The P3 component exhibited enhanced brain activity in response to faces preceded by happy and fearful eyes compared with neutral eyes, indicating motivated attention processing may be involved at this stage. Altogether, these results indicate for the first time that the influence of isolated eye regions on the perception of surprised faces involves preferential processing at the early stages and elaborate processing at the late stages. Moreover, higher cognitive processes such as predictions and attention can modulate face processing from the earliest stages in a top‐down manner.     

Behavioral approach and reward processing: results on feedback-related negativity and P3 component

This study examined the FRN, the P3, and individual differences in trait-BAS and trait-BIS in the context of reward expectation mismatch. A more negative FRN was predicted for higher vs. lower trait-BAS individuals and for higher vs. lower trait-BIS individuals. In the extinction-learning task, participants (N = 102) chose between two response buttons to earn a maximum of points. In the acquisition phase, button 1 was continuously rewarded and button 2 was partially rewarded. In the extinction phase, one button was unexpectedly no longer rewarded. The FRN amplitude was more negative for higher vs. lower trait-BAS individuals and for lower vs. higher trait-BIS individuals within the extinction phase. The P3 was more positive in the extinction compared to the acquisition phase. Our results suggest that higher trait-BAS individuals have a more pronounced reward expectation mismatch.     

Gesture influences the processing of figurative language in non-native speakers: ERP evidence

Gestures should play a role in second language comprehension, given their importance in conveying contextual information. In this study, the N400 and the LPC were evaluated in a task involving the observation of videos showing utterances accompanied by gestures. Students studying advanced (G-High participants) and basic German (G-Low participants) as a second language were investigated. The utterance–gesture congruence and metaphoric meaning of content were manipulated during the task. As in previous ERP reports with native speakers, metaphorical expressions were sensitive to gestures. In G-Low participants, no modulation in the 300–500 ms window was observed, and only a modest effect was observed for the 500–700 ms window. More subtle differences of verbal expression were not processed in this group. Consistent with previous reports of the same paradigm with native speakers, the N400 from G-High group discriminated both congruent and incongruent gestures as well as literal and metaphorical sentences. Our results suggest that semantic processing is robust in the learning of a second language, although the amplitude modulation and latency of ERPs might depend on the speaker's proficiency level.     

Teasing apart the anticipatory and consummatory processing of monetary incentives: An event‐related potential study of reward dynamics

The monetary incentive delay (MID) task has been widely used in fMRI studies to investigate the neural networks involved in anticipatory and consummatory reward processing. Previous efforts to adapt the MID task for use with ERPs, however, have had limited success. Here, we sought to further decompose reward dynamics using a comprehensive set of anticipatory (cue‐N2, cue‐P3, contingent negative variation [CNV]) and consummatory ERPs (feedback negativity [FN], feedback P3 [fb‐P3]). ERP data was recorded during adapted versions of the MID task across two experiments. Unlike previous studies, monetary incentive cues modulated the cue‐N2, cue‐P3, and CNV; however, cue‐related ERPs and the CNV were uncorrelated with one another, indicating distinct anticipatory subprocesses. With regard to consummatory processing, FN amplitude primarily tracked outcome valence (reward vs. nonreward), whereas fb‐P3 amplitude primarily tracked outcome salience (uncertain vs. certain). Independent modulation of the cue‐P3 and fb‐P3 was observed, indicating that these two P3 responses may uniquely capture the allocation of attention during anticipatory and consummatory reward processing, respectively. Overall, across two samples, consistent evidence of both anticipatory and consummatory ERP activity was observed on an adapted version of the MID paradigm, demonstrating for the first time how these ERP components may be integrated with one another to more fully characterize the time course of reward processing. This ERP‐MID paradigm is well suited to parsing reward dynamics, and can be applied to both healthy and clinical populations.     

Effects of prior mental effort on picture processing: An ERP investigation

The current study examined the aftereffects of mental effort on the processing of picture stimuli using neural measures. Ninety‐seven healthy young adults were randomly assigned to exercise more versus less mental effort on a writing task. Then participants viewed positive, negative, and neutral affective images while P1, N1, P2, N2, P3, and late positive potential (LPP) magnitudes to the images were assessed. We found that performing the more (versus less) effortful writing task caused more negative N2 amplitudes to all images. In addition, and consistent with past research, emotional (versus neutral) images elicited more positive amplitudes on the N2, P3, and LPP components. Thus, prior mental effort appeared to reduce early attentional engagement with visual stimuli but did not diminish later attention modulation by emotional content. These findings suggest novel implications for understanding the behavioral aftereffects of mental effort and self‐control.     

Implicit conditioning of faces via the social regulation of emotion: ERP evidence of early attentional biases for security conditioned faces

Not much is known about the neural and psychological processes that promote the initial conditions necessary for positive social bonding. This study explores one method of conditioned bonding utilizing dynamics related to the social regulation of emotion and attachment theory. This form of conditioning involves repeated presentations of negative stimuli followed by images of warm, smiling faces. L. Beckes, J. Simpson, and A. Erickson (2010) found that this conditioning procedure results in positive associations with the faces measured via a lexical decision task, suggesting they are perceived as comforting. This study found that the P1 ERP was similarly modified by this conditioning procedure and the P1 amplitude predicted lexical decision times to insecure words primed by the faces. The findings have implications for understanding how the brain detects supportive people, the flexibility and modifiability of early ERP components, and social bonding more broadly.     

Interaction of facial expressions and familiarity: ERP evidence

There is mounting evidence that under some conditions the processing of facial identity and facial emotional expressions may not be independent; however, the nature of this interaction remains to be established. By using event-related brain potentials (ERP) we attempted to localize these interactions within the information processing system. During an expression discrimination task (Experiment 1) categorization was faster for portraits of personally familiar vs. unfamiliar persons displaying happiness. The peak latency of the P300 (trend) and the onset of the stimulus-locked LRP were shorter for familiar than unfamiliar faces. This implies a late perceptual but pre-motoric locus of the facilitating effect of familiarity on expression categorization. In Experiment 2 participants performed familiarity decisions about portraits expressing different emotions. Results revealed an advantage of happiness over disgust specifically for familiar faces. The facilitation was localized in the response selection stage as suggested by a shorter onset of the LRP. Both experiments indicate that familiarity and facial expression may not be independent processes. However, depending on the kind of decision different processing stages may be facilitated for happy familiar faces.     

The effect of sleep continuity disruption on multimodal emotion processing and regulation: a laboratory-based,randomised, controlled experiment in good sleepers

Previous research shows that experimental sleep deprivation alters emotion processing, suggesting a potential mechanism linking sleep disruption to mental ill-health. Extending previous work, we experimentally disrupted sleep continuity in good sleepers and assessed next-day emotion processing and regulation using tasks with established sensitivity to depression. In a laboratory-based study, 51 good sleepers (37 female; mean [SD] age 24 [3.63] years), were randomised to 1 night of uninterrupted sleep (n = 24) or sleep continuity disruption (n = 27). We assessed emotion perception, attention, and memory the following day. Participants also completed an emotion regulation task and measures of self-reported affect, anxiety, sleepiness, overnight declarative memory consolidation, and psychomotor vigilance. Confirming the effects of the manipulation, sleep continuity disruption led to a marked decrease in polysomnography-defined total sleep time (229.98 versus 434.57 min), increased wake-time after sleep onset (260.66 versus 23.84 min), and increased sleepiness (d = 0.81). Sleep continuity disruption led to increased anxiety (d = 0.68), decreased positive affect (d = −0.62), reduced overnight declarative memory consolidation (d = −1.08), and reduced psychomotor vigilance (longer reaction times [d = 0.64] and more lapses [d = 0.74]), relative to control. However, contrary to our hypotheses, experimental sleep disruption had no effect on perception of, or bias for, emotional facial expressions, emotional memory for words, or emotion regulation following worry induction. In conclusion, 1 night of sleep continuity disruption had no appreciable effect on objective measures of emotion processing or emotion regulation in response to worry induction, despite clear effects on memory consolidation, vigilance, and self-reported affect and anxiety.     

消极情绪背景下大学生内隐情绪调节对注意瞬脱的影响

目的:考察在消极情绪背景下内隐情绪调节对注意瞬脱的影响。方法:选取50名大学生,随机等分为启动情绪控制调节目标的调节组和未启动的非调节组,采用情绪性操作诱发被试的消极情绪,通过词语搭配任务启动情绪控制调节目标,比较两组被试对注意瞬脱任务两个靶刺激(T1和T2位置上的数字)的反应正确率。结果:在完成内隐情绪调节目标启动后,调节组被试的内隐消极情绪得分低于非调节组[(1.98±0.56) vs.(2.05±0.40),P=0.044]。当T2在T1呈现后的200～500 ms内呈现时,两组被试对T2的正确报告率均显著下降,调节组对T2的反正正确率低于非调节组被试,表现出更明显的注意瞬脱效应[Lag4:(86.12%vs.92.92%),P<0.05;Lag5:(93.56%vs.98.48%),P<0.05]。结论:消极情绪背景下大学生启动情绪控制目标能降低内隐消极情绪体验,同时表现出更强的注意瞬脱效应。     

Dissociable effects of psychopathic traits on cortical and subcortical visual pathways during facial emotion processing: An ERP study on the N170

This study examined the relation between psychopathic traits and the brain response to facial emotion by analyzing the N170 component of the ERP. Fifty‐four healthy participants were assessed for psychopathic traits and exposed to images of emotional and neutral faces with varying spatial frequency content. The N170 was modulated by the emotional expressions, irrespective of psychopathic traits. Fearless dominance was associated with a reduced N170, driven by the low spatial frequency components of the stimuli, and dependent on the tectopulvinar visual pathway. Conversely, coldheartedness was related to overall enhanced N170, suggesting mediation by geniculostriate processing. Results suggest that different dimensions of psychopathy are related to distinct facial emotion processing mechanisms and support the existence of both amygdala deficits and compensatory engagement of cortical structures for emotional processing in psychopathy.     

Infants' neutral facial expressions elicit the strongest initial attentional bias in adults: Behavioral and electrophysiological evidence

Recent studies that used adult faces as the baseline have revealed that attentional bias toward infant faces is the strongest for neutral expressions than for happy and sad expressions. However, the time course of the strongest attentional bias toward infant neutral expressions is unclear. To clarify this time course, we combined a behavioral dot-probe task with electrophysiological event-related potentials (ERPs) to measure adults' responses to infant and adult faces with happy, neutral, and sad expressions derived from the same face. The results indicated that compared with the corresponding expressions in adult faces, attentional bias toward infant faces with various expressions resulted in different patterns during rapid and prolonged attention stages. In particular, first, neutral expressions in infant faces elicited greater behavioral attentional bias and P1 responses than happy and sad ones did. Second, sad expressions in infant faces elicited greater N170 responses than neutral and happy ones did; notably, sad expressions elicited greater N170 responses in the left hemisphere in women than in men. Third, late positive potential (LPP) responses were greater for infant faces than for adult faces under each expression condition. Thus, we propose a three-stage model of attentional allocation patterns that reveals the time course of attentional bias toward infant faces with various expressions. This model highlights the prominent role of neutral facial expressions in the attentional bias toward infant faces.     

Event‐related potentials of attentional bias toward faces in the dot‐probe task: A systematic review

The dot‐probe task is a common task to assess attentional bias toward different stimuli and how groups differ (e.g., attentional bias in anxiety disorders). However, measuring reaction time has been suggested to be unreliable. Neuroimaging methods such as fMRI were shown to be more reliable in assessing attentional bias, but fMRI has poor temporal resolution and therefore cannot assess timing of attention. ERPs have been used to examine the time course of attentional bias. Although ERP research may be more reliable than reaction time, there have been inconsistencies in the literature. This review systematically searched for articles that used the dot‐probe task with facial expressions and measured neural correlates with ERP. We found that some of the inconsistencies might be the cause of methodological differences (e.g., timing of stimuli), differences in emotional expression, and/or sample differences (e.g., sex, age, etc.). Suggestions on how future research could address the issues presented in this review were discussed.     

The processing of anticipated and unanticipated fearful faces: An ERP study

This study examined the processing of fearful and neutral expressions, which could either be anticipated or not from a prime word (i.e., 'fear' or 'neutral') with or without predictive value. In total, data from 17 participants (i.e., reaction times; ERP waveforms) were analyzed. ERP data showed that the expression effect (fearful vs. neutral faces) was different between predictable and unpredictable trials in early components (N1, N170 and P2) after face onset. However, the expression effect was essentially the same between predictable and unpredictable trials in late components (N300 and P3) after face onset. These results revealed that emotion processing of anticipated vs. non-anticipated stimuli differs mainly in the early stage of neural activity after face onset.     

The contribution of the fusiform gyrus and superior temporal sulcus in processing facial attractiveness: neuropsychological and neuroimaging evidence

Current cognitive models suggest that the processing of dynamic facial attributes, including social signals such as gaze direction and facial expression, involves the superior temporal sulcus, whereas the processing of invariant facial structure such as the individuals' identity involves the fusiform face area. Where facial attractiveness, a social signal that may emerge from invariant facial structure, is processed within this dual-route model of face perception is uncertain. Here, we present two studies. First, we investigated the explicit judgments of facial attractiveness and attractiveness-motivated behavior in patients with acquired prosopagnosia, a deficit in familiar face recognition usually associated with damage to medial occipitotemporal cortex. We found that both abilities were impaired in these patients, with some weak residual ability for attractiveness judgments found only in those patients with unilateral right occipitotemporal or bilateral anterior temporal lesions. Importantly, deficits in attractiveness perception correlated with the severity of the face recognition deficit. Second, we performed a functional magnetic resonance imaging study in healthy subjects that included an implicit and explicit processing of facial attractiveness. We found increased neural activity when explicitly judging facial attractiveness within a number of cortical regions including the fusiform face area, but not the superior temporal sulcus, indicating a potential contribution of the fusiform face area to this judgment. Thus, converging neuropsychological and neuroimaging evidence points to a critical role of the inferior occipitotemporal cortex in the processing of facial attractiveness.