Differences in startle reactivity during the perception of angry and fearful faces

Emotion researchers often categorize angry and fearful face stimuli as "negative" or "threatening". Perception of fear and anger, however, appears to be mediated by dissociable neural circuitries and often elicit distinguishable behavioral responses. The authors sought to elucidate whether viewing anger and fear expressions produce dissociable psychophysiological responses (i.e., the startle reflex). The results of two experiments using different facial stimulus sets (representing anger, fear, neutral, and happy) indicated that viewing anger was associated with a significantly heightened startle response (p < .05) relative to viewing fear, happy, and neutral. This finding suggests that while anger and fear faces convey messages of "threat", their priming effect on startle circuitry differs. Thus, angry expressions, representing viewer-directed threat with an unambiguous source (i.e., the expresser), may more effectively induce a motivational propensity to withdraw or escape. The source of threat is comparatively less clear for fearful faces. The differential effects of these two facial threat signals on the defensive motivational system adds to growing literature highlighting the importance of distinguishing between emotional stimuli of similar valence, along lines of meaning and functional impact.     

Rapid reactions to direct and averted facial expressions of fear and anger

Recent studies have shown that reaction times to expressions of anger with averted gaze and fear with direct gaze appear slower than those to direct anger and averted fear. Such findings have been explained by appealing to the notion of gaze/expression congruence with aversion (avoidance) associated with fear, whereas directness (approach) is associated with anger. The current study examined reactions to briefly presented direct and averted faces displaying expressions of fear and anger. Participants were shown four blocked series of faces; each block contained an equal mix of two facial expressions (neutral plus either fear or anger) presented at one viewpoint (either full face or three quarter leftward facing). Participants were instructed to make rapid responses classifying the expressions as either neutral or expressive. Initial analysis of reaction time distributions showed differences in distribution shape with reactions to averted anger and direct fear showing greater skew than those to direct anger and averted fear. Computational modelling, using a diffusion model of decision making and reaction time, showed a difference in the rate of information accrual with more rapid rates of accrual when viewpoint and expression were congruent. This analysis supports the notion of signal congruence as a mechanism through which gaze and viewpoint affect our responses to facial expressions.     

Looking at You or Looking Elsewhere: The Influence of Head Orientation on the Signal Value of Emotional Facial Expressions

The role of horizontal head tilt for the perceptions of emotional facial expressions was examined. For this, a total of 387 participants rated facial expressions of anger, fear, sadness, and happiness, as well as neutral expressions shown by two men and two women in either a direct or an averted face angle. Decoding accuracy, attributions of dominance and affiliation, emotional reactions of the perceivers, and the felt desire to approach the expresser were assessed. Head position was found to strongly influence reactions to anger and fear but less so for other emotions. Direct anger expressions were more accurately decoded, perceived as less affiliative, and elicited higher levels of anxiousness and repulsion, as well as less desire to approach than did averted anger expressions. Conversely, for fear expressions averted faces elicited more negative affect in the perceiver. These findings suggest that horizontal head position is an important cue for the assessment of threat.

Emotional expressions forecast approach-avoidance behavior

The contention that basic behavioral intentions are forecasted by emotional expressions has received surprisingly little empirical support. We introduce a behavioral task that gauges the speed with which movement of angry and fearful faces (toward or away from an expressor's gaze) are accurately detected. In two studies we found that perceivers were faster to correctly detect approaching anger faces (i.e., faces that moved in the direction of their own gaze). The opposite, however, was not true for fear expressions. These findings offer evidence that, at least for anger displays, the basic behavioral intent to approach is strongly transmitted and at very low-levels of processing, even priming congruent behavioral responses in observers. The null results for fear faces may indicate that these signal a “freezing” response or behavioral inhibition rather than flight per se. The results of this work are discussed in relation to contemporary theories of emotion.     

The influence of the fear facial expression on prosocial responding

Perceiving distress cues appears to be associated with prosocial responding. This being the case, it was hypothesised that the fear facial expression would elicit prosocial responding in perceivers. In Study 1, participants indicated that fear and sadness expressions would be associated with greater sympathy and willingness to help the expresser than would neutral expressions. In Study 2, participants were primed with fear or neutral expressions before reading vignettes featuring protagonists in mild distress. Fear-primed participants reported more sympathy and desire to help the protagonists than neutral-primed participants. Moreover, participants who recognised fear most accurately, as measured by a standard facial expression recognition task, showed the greatest increases in prosocial responding following fear expression primes. This corroborates the notion, supported by research as disparate as behavioural research on bystander intervention and clinical research on psychopaths, that exposure to and correct interpretation of certain distress cues may predict an individual's likelihood of behaving prosocially.     

The influence of emotion type,social value orientation and processing focus on approach-avoidance tendencies to negative dynamic facial expressions

Facial expressions of anger and fear have been seen to elicit avoidance behavior in the perceiver due to their negative valence. However, recent research uncovered discrepancies regarding these immediate motivational implications of fear and anger, suggesting that not all negative emotions trigger avoidance to a comparable extent. To clarify those discrepancies, we considered recent theoretical and methodological advances, and investigated the role of social preferences and processing focus on approach-avoidance tendencies (AAT) to negative facial expressions. We exposed participants to dynamic facial expressions of anger, disgust, fear, or sadness, while they processed either the emotional expression or the gender of the faces. AATs were assessed by reaction times of lever movements, and by posture changes via head-tracking. We found that—relative to angry faces-, fearful and sad faces triggered more approach, with a larger difference between fear and anger in prosocial compared to individualistic participants. Interestingly, these findings are in line with a recently developed concern hypothesis, suggesting that—relative to other negative expressions—expressions of distress may facilitate approach, especially in participants with prosocial preferences.     

When time stands still: fear-specific modulation of temporal bias due to threat

The current study was designed to test the fear-specific nature of temporal bias due to threat. A temporal bisection procedure was used in which participants (N = 46) were initially trained to recognize short (400 ms) and long (1,600 ms) standard durations. In the test phase, participants were asked to judge whether the duration of computer-generated faces drawn to appear threatening, fearful, and neutral, was closer to either the short or long duration they had learnt earlier. Past research was replicated-the durations of the arousing facial expressions were overestimated relative to a low arousal (neutral) expression. Overestimation for threat was positively correlated with individual differences in fearfulness, trait anxiety, and distress. Multiple regression analyses were carried out to test the hypothesis was that individual differences in anxiety and fearfulness but not other traits would uniquely predict temporal overestimation due to threat. The results showed that fearfulness but not other traits (trait anxiety, anger, distress, activity, and sociability) was a unique and strong (partial r = .47) predictor of increased overestimation for both threatening and fearful expressions. The findings support the hypothesis that threat-related expressions activate a fear-specific system (?hman & Mineka, 2001) or fear representations (Beck & Clark, 1997) in fearful individuals.     

高低特质攻击个体对威胁面部表情识别的差异研究——来自ERP的证据

为揭示高特质攻击个体对愤怒、恐惧威胁面部表情识别的特点及其电生理机制，本研究采用Buss-Perry攻击问卷选取高低特质攻击个体26名和27名为被试，采用面孔识别范式对高低特质攻击个体识别威胁面部表情时的ERP差异进行研究。结果发现，在愤怒、恐惧表情上，高特质攻击组在N170成分的潜伏期都显著短于低特质攻击组；在愤怒、恐惧表情上，高特质攻击组在P200成分的波幅都显著高于低特质攻击组。这表明高特质攻击个体对愤怒、恐惧威胁面部表情的识别具有高度敏感性，这种敏感性体现在面部表情识别的早期和中期阶段，而非晚期阶段，即高特质攻击个体在早期的前注意阶段就对愤怒、恐惧威胁面部表情进行优先注意；在中期的注意阶段，高特质攻击个体可以很好地确认愤怒、恐惧威胁面部表情。     

Testosterone reduces conscious detection of signals serving social correction: implications for antisocial behavior

Elevated levels of testosterone have repeatedly been associated with antisocial behavior, but the psychobiological mechanisms underlying this effect are unknown. However, testosterone is evidently capable of altering the processing of facial threat, and facial signals of fear and anger serve sociality through their higher-level empathy-provoking and socially corrective properties. We investigated the hypothesis that testosterone predisposes people to antisocial behavior by reducing conscious recognition of facial threat. In a within-subjects design, testosterone (0.5 mg) or placebo was administered to 16 female volunteers. Afterward, a task with morphed stimuli indexed their sensitivity for consciously recognizing the facial expressions of threat (disgust, fear, and anger) and nonthreat (surprise, sadness, and happiness). Testosterone induced a significant reduction in the conscious recognition of facial threat overall. Separate analyses for the three categories of threat faces indicated that this effect was reliable for angry facial expressions exclusively. This testosterone-induced impairment in the conscious detection of the socially corrective facial signal of anger may predispose individuals to antisocial behavior.     

Gender of the expresser moderates the effect of emotional faces on the startle reflex

It has been suggested that the impact of emotional expressions on the startle reflex is influenced by the intention communicated by the expression (e.g., the intention to attack). However, we propose that the meaning of an emotional expression is not only based on the intention, but is also influenced by characteristics of the expresser such as gender: since men are typically seen as more dominant than women, anger expressed by men should be perceived as particularly threatening, thus amplifying the startle response. We compared the influence of anger, fear and neutral expressions shown by men and women on the startle reaction. Startle reactions were measured using electromyography. As predicted, we found stronger startle reactions after the presentation of anger expressed by men compared to fearful and neutral expressions shown by men. For female expressers, the startle response was not affected by expression type.     

Conserved evolutionary history for quick detection of threatening faces

Humans quickly recognize threats such as snakes and threatening faces, suggesting that human ancestors evolved specialized visual systems to detect biologically relevant threat stimuli. Although non-human primates also detect snakes quickly, it is unclear whether primates share the efficient visual systems to process the threatening faces of their conspecifics. Primates may not necessarily process conspecific threats by facial expressions, because threats from conspecifics in natural situations are often accompanied by other cues such as threatening actions (or attacks) and vocal calls. Here, we show a similar threat superiority effect in both humans and macaque Japanese monkeys. In visual search tasks, monkeys and humans both responded to pictures of a threatening face of an unfamiliar adult male monkey among neutral faces faster than to pictures of a neutral face among threatening faces. However, the monkeys’ response times to detect deviant pictures of a non-face stimulus were not slower when it was shown among threat faces than when it was shown among neutral faces. These results provide the first evidence that monkeys have an attentional bias toward the threatening faces of conspecifics and suggest that threatening faces are evolutionarily relevant fear stimuli. The subcortical visual systems in primates likely process not only snakes, but also more general biological threat-relevant stimuli, including threatening conspecific faces.     

Relationships between perceptual defence reactions and subjective tendencies in the phenomenal representation of facial displays of affect

The present study examines if non-veridical reports of a stimulus-motif presented below the threshold for correct recognition are related to subjective tendencies in the ordinary perception of thermatically related stimuli. Sixty-four subjects were tested with the standard picture of Kragh's Defence Mechanism Test (DMT) which reflects a theme of aggression and threat. Stimulus-inadequate report of the picture-motif were related to the subject's phenomenal representation of video-recorded facial displays of anger, fear, sadness, and joy. The results demonstrate a correspondence between the individual's perceptual distortions, eliminations, or additions to the threatening subliminal stimulus and his or her phenomenal representation of the supraliminal affective stimuli.     

The automaticity of emotion recognition

Evolutionary accounts of emotion typically assume that humans evolved to quickly and efficiently recognize emotion expressions because these expressions convey fitness-enhancing messages. The present research tested this assumption in 2 studies. Specifically, the authors examined (a) how quickly perceivers could recognize expressions of anger, contempt, disgust, embarrassment, fear, happiness, pride, sadness, shame, and surprise; (b) whether accuracy is improved when perceivers deliberate about each expression's meaning (vs. respond as quickly as possible); and (c) whether accurate recognition can occur under cognitive load. Across both studies, perceivers quickly and efficiently (i.e., under cognitive load) recognized most emotion expressions, including the self-conscious emotions of pride, embarrassment, and shame. Deliberation improved accuracy in some cases, but these improvements were relatively small. Discussion focuses on the implications of these findings for the cognitive processes underlying emotion recognition.     

A Role for the Human Amygdala in Recognizing Emotional Arousal From Unpleasant Stimuli

Functional neuroimaging and lesion-based neuropsychological experiments have demonstrated the human amygdala's role in recognition of certain emotions signaled by sensory stimuli, notably, fear and anger in facial expressions. We examined recognition of two emotional dimensions, arousal and valence, in a rare subject with complete, bilateral damage restricted to the amygdala. Recognition of emotional arousal was impaired for facial expressions, words, and sentences that depicted unpleasant emotions, especially in regard to fear and anger. However, recognition of emotional valence was normal. The findings suggest that the amygdala plays a critical role in knowledge concerning the arousal of negative emotions, a function that may explain the impaired recognition of fear and anger in patients with bilateral amygdala damage, and one that is consistent with the amygdala's role in processing stimuli related to threat and danger.     

Affective divergence: automatic responses to others' emotions depend on group membership

Extant research suggests that targets' emotion expressions automatically evoke similar affect in perceivers. The authors hypothesized that the automatic impact of emotion expressions depends on group membership. In Experiments 1 and 2, an affective priming paradigm was used to measure immediate and preconscious affective responses to same-race or other-race emotion expressions. In Experiment 3, spontaneous vocal affect was measured as participants described the emotions of an ingroup or outgroup sports team fan. In these experiments, immediate and spontaneous affective responses depended on whether the emotional target was ingroup or outgroup. Positive responses to fear expressions and negative responses to joy expressions were observed in outgroup perceivers, relative to ingroup perceivers. In Experiments 4 and 5, discrete emotional responses were examined. In a lexical decision task (Experiment 4), facial expressions of joy elicited fear in outgroup perceivers, relative to ingroup perceivers. In contrast, facial expressions of fear elicited less fear in outgroup than in ingroup perceivers. In Experiment 5, felt dominance mediated emotional responses to ingroup and outgroup vocal emotion. These data support a signal-value model in which emotion expressions signal environmental conditions.     

Emotional memory and perception of emotional faces in patients suffering from depersonalization disorder

Previous work has shown that patients with depersonalization disorder (DPD) have reduced physiological responses to emotional stimuli, which may be related to subjective emotional numbing. This study investigated two aspects of affective processing in 13 patients with DPD according to the DSM‐IV criteria and healthy controls: the perception of emotional facial expressions (anger, disgust, fear, happiness, sadness, and surprise) and memory for emotional stimuli. Results revealed a specific lack of sensitivity to facial expression of anger in patients, but normal enhancement of memory for peripheral aspects of arousing emotional material. The results are consistent with altered processing of threat‐related stimuli but intact consolidation processes, at least when the stimuli involved are potently arousing.     

BRIEF REPORT

We employed a psychophysiological marker of directed attention (the visual scanpath) to investigate visuocognitive processing of particular facial expressions in healthy individuals (N = 47). Visual scanpaths were recorded using video-oculography while subjects viewed digitised photographs of threat-related (fear, anger) and nonthreat (sad, happy, neutral) facial expressions. Hypotheses regarding the existence of a differential viewing strategy for threat-related facial expressions were based upon the adaptive significance of rapid detection and effective appraisal of social threat from conspecific face stimuli. When compared with each of the nonthreat faces, viewing strategies for expressions of anger and fear were characterised by increased distance between fixations (extended scanning), with more fixations, of longer duration, to feature areas of these faces. The extended scanning style suggests that threat-related faces evoke a "vigilant" style of scanning, whereby longer saccadic eye movements may reflect heightened autonomic responses to threat, while the increased foveal attention to feature areas of threat-related faces may facilitate cognitive appraisal of the personal significance and direction of impending threat. These results suggest the existence of distinct visuocognitive patterns for processing threat-related facial expressions, in response to the evolutionary advantage of detecting and appraising social threat.     

Drawn to danger: trait anger predicts automatic approach behaviour to angry faces

Most people automatically withdraw from socially threatening situations. However, people high in trait anger could be an exception to this rule, and may even display an eagerness to approach hostile situations. To test this hypothesis, we asked 118 participants to complete an approach-avoidance task, in which participants made approach or avoidance movements towards faces with an angry or happy expression, and a direct or averted eye gaze. As expected, higher trait anger predicted faster approach (than avoidance) movements towards angry faces. Crucially, this effect occurred only for angry faces with a direct eye gaze, presumably because they pose a specific social threat, in contrast to angry faces with an averted gaze. No parallel effects were observed for happy faces, indicating that the effects of trait anger were specific to hostile stimuli. These findings suggest that people high in trait anger may automatically approach hostile interaction partners.     

The facilitated processing of threatening faces: an ERP analysis

Threatening, friendly, and neutral faces were presented to test the hypothesis of the facilitated perceptual processing of threatening faces. Dense sensor event-related brain potentials were measured while subjects viewed facial stimuli. Subjects had no explicit task for emotional categorization of the faces. Assessing early perceptual stimulus processing, threatening faces elicited an early posterior negativity compared with nonthreatening neutral or friendly expressions. Moreover, at later stages of stimulus processing, facial threat also elicited augmented late positive potentials relative to the other facial expressions, indicating the more elaborate perceptual analysis of these stimuli. Taken together, these data demonstrate the facilitated perceptual processing of threatening faces. Results are discussed within the context of an evolved module of fear (A. Ohman & S. Mineka, 2001).     

Why do fear and anger look the way they do? Form and social function in facial expressions

The origins of the appearances of anger and fear facial expressions are not well understood. The authors tested the hypothesis that such origins might lie in the expressions' resemblance to, respectively, mature and babyish faces in three studies. In Study 1, faces expressing anger and fear were judged to physically resemble mature and babyish faces. Study 2 indicated that characteristics associated specifically with babyishness are attributed to persons showing fear, whereas characteristics associated with maturity are attributed to persons showing anger. In Study 3, composite faces were used to minimize the possibility that the attributions were based on associations to the anger and fear emotions alone rather than to the physical resemblance of the expressions to static facial appearance cues. These results suggest that fear and anger expressions may serve socially adaptive purposes for those who show them, similar to the social adaptations associated with a babyish or mature facial appearance.