Modeling automatic threat detection: Development of a face-in-the-crowd task.

An angry face is expected to be detected faster than a happy face because of an early, stimulus-driven analysis of threat-related properties. However, it is unclear to what extent results from the visual search approach—the face-in-the-crowd task—mirror this automatic analysis. The paper outlines a model of automatic threat detection that combines the assumption of a neuronal system for threat detection with contemporary theories of visual search. The model served as a guideline for the development of a new face-in-the-crowd task. The development involved three preliminary studies that provided a basis for the selection of angry and happy facial stimuli resembling each other in respect to perceptibility, homogeneity, and intensity. With these stimuli a signal detection version of the search task was designed and tested. For crowds composed of neutral faces, the sensitivity measure d′ proved the expected detection advantage of angry faces compared to happy faces. However, the emotional expression made no difference if a neutral face had to be detected in crowd composed of either angry or happy faces. Results are in line with the assumption of a stimulus-driven shift of attention giving rise to the superior detection of angry target faces. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Judging approachability on the face of it: The influence of face and body expressions on the perception of approachability.

The aim of the current study was to examine how emotional expressions displayed by the face and body influence the decision to approach or avoid another individual. In Experiment 1, we examined approachability judgments provided to faces and bodies presented in isolation that were displaying angry, happy, and neutral expressions. Results revealed that angry expressions were associated with the most negative approachability ratings, for both faces and bodies. The effect of happy expressions was shown to differ for faces and bodies, with happy faces judged more approachable than neutral faces, whereas neutral bodies were considered more approachable than happy bodies. In Experiment 2, we sought to examine how we integrate emotional expressions depicted in the face and body when judging the approachability of face-body composite images. Our results revealed that approachability judgments given to face-body composites were driven largely by the facial expression. In Experiment 3, we then aimed to determine how the categorization of body expression is affected by facial expressions. This experiment revealed that body expressions were less accurately recognized when the accompanying facial expression was incongruent than when neutral. These findings suggest that the meaning extracted from a body expression is critically dependent on the valence of the associated facial expression. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

The face in the crowd effect unconfounded: Happy faces, not angry faces, are more efficiently detected in single- and multiple-target visual search tasks.

Is it easier to detect angry or happy facial expressions in crowds of faces? The present studies used several variations of the visual search task to assess whether people selectively attend to expressive faces. Contrary to widely cited studies (e.g., ?hman, Lundqvist, & Esteves, 2001) that suggest angry faces “pop out” of crowds, our review of the literature found inconsistent evidence for the effect and suggested that low-level visual confounds could not be ruled out as the driving force behind the anger superiority effect. We then conducted 7 experiments, carefully designed to eliminate many of the confounding variables present in past demonstrations. These experiments showed no evidence that angry faces popped out of crowds or even that they were efficiently detected. These experiments instead revealed a search asymmetry favoring happy faces. Moreover, in contrast to most previous studies, the happiness superiority effect was shown to be robust even when obvious perceptual confounds—like the contrast of white exposed teeth that are typically displayed in smiling faces—were eliminated in the happy targets. Rather than attribute this effect to the existence of innate happiness detectors, we speculate that the human expression of happiness has evolved to be more visually discriminable because its communicative intent is less ambiguous than other facial expressions. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Binocular rivalry: A window into emotional processing in aging.

Previous binocular rivalry studies with younger adults have shown that emotional stimuli dominate perception over neutral stimuli. Here we investigated the effects of age on patterns of emotional dominance during binocular rivalry. Participants performed a face/house rivalry task where the emotion of the face (happy, angry, neutral) and orientation (upright, inverted) of the face and house stimuli were varied systematically. Age differences were found with younger adults showing a general emotionality effect (happy and angry faces were more dominant than neutral faces) and older adults showing inhibition of anger (neutral faces were more dominant than angry faces) and positivity effects (happy faces were more dominant than both angry and neutral faces). Age differences in dominance patterns were reflected by slower rivalry rates for both happy and angry compared to neutral face/house pairs in younger adults, and slower rivalry rates for happy compared to both angry and neutral face/house pairs in older adults. Importantly, these patterns of emotional dominance and slower rivalry rates for emotional-face/house pairs disappeared when the stimuli were inverted. This suggests that emotional valence, and not low-level image features, were responsible for the emotional bias in both age groups. Given that binocular rivalry has a limited role for voluntary control, the findings imply that anger suppression and positivity effects in older adults may extend to more automatic tasks. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Young and older emotional faces: Are there age group differences in expression identification and memory?

Studies have found that older compared with young adults are less able to identify facial expressions and have worse memory for negative than for positive faces, but those studies have used only young faces. Studies finding that both age groups are more accurate at recognizing faces of their own than other ages have used mostly neutral faces. Thus, age differences in processing faces may not extend to older faces, and preferential memory for own age faces may not extend to emotional faces. To investigate these possibilities, young and older participants viewed young and older faces presented either with happy, angry, or neutral expressions; participants identified the expressions displayed and then completed a surprise face recognition task. Older compared with young participants were less able to identify expressions of angry young and older faces and (based on participants’ categorizations) remembered angry faces less well than happy faces. There was no evidence of an own age bias in memory, but self-reported frequency of contact with young and older adults and awareness of own emotions played a role in expression identification of and memory for young and older faces. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Task-irrelevant angry faces capture attention in visual search while modulated by resources.

We investigated the attentional capture effect of emotional faces under sufficient or restricted attentional conditions. In a modified visual search paradigm, three kinds of schematic faces (angry, happy, and neutral) served as stimuli. Participants were instructed to search for a target face indicated by a dot and to respond to the dot's position. In this design, the emotional content of the face is task-irrelevant and does not need to be attended. The results of Experiment 1 demonstrate that having an angry face as the target face elicited a faster response than did the neutral target face, and when the angry face is used as a distractor, the response to the target was delayed compared to the response with no such distractor. Experiment 2 included inverted faces to decrease emotional content; results showed that inversion of the faces reduced the effect of angry faces on the search performance. When attention was cued to a specific area in Experiment 3, the effect of angry faces outside of the cued area became weaker. In conclusion, the results indicate that a task-irrelevant angry face can capture attention beyond top-down control, but this effect is modulated by the availability of attentional resources. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

No effect of inversion on attentional and affective processing of facial expressions.

The decrease in recognition performance after face inversion has been taken to suggest that faces are processed holistically. Three experiments, 1 with schematic and 2 with photographic faces, were conducted to assess whether face inversion also affected visual search for and implicit evaluation of facial expressions of emotion. The 3 visual search experiments yielded the same differences in detection speed between different facial expressions of emotion for upright and inverted faces. Threat superiority effects, faster detection of angry than of happy faces among neutral background faces, were evident in 2 experiments. Face inversion did not affect explicit or implicit evaluation of face stimuli as assessed with verbal ratings and affective priming. Happy faces were evaluated as more positive than angry, sad, or fearful/scheming ones regardless of orientation. Taken together these results seem to suggest that the processing of facial expressions of emotion is not impaired if holistic processing is disrupted. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Temporal processing of emotional stimuli: The capture and release of attention by angry faces.

Neuroimaging data suggest that emotional information, especially threatening faces, automatically captures attention and receives rapid processing. While this is consistent with the majority of behavioral data, behavioral studies of the attentional blink (AB) additionally reveal that aversive emotional first target (T1) stimuli are associated with prolonged attentional engagement or “dwell” time. One explanation for this difference is that few AB studies have utilized manipulations of facial emotion as the T1. To address this, schematic faces varying in expression (neutral, angry, happy) served as the T1 in the current research. Results revealed that the blink associated with an angry T1 face was, primarily, of greater magnitude than that associated with either a neutral or happy T1 face, and also that initial recovery from this processing bias was faster following angry, compared with happy, T1 faces. The current data therefore provide important information regarding the time-course of attentional capture by angry faces: Angry faces are associated with both the rapid capture and rapid release of attention. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

The confounded nature of angry men and happy women.

Findings of 7 studies suggested that decisions about the sex of a face and the emotional expressions of anger or happiness are not independent: Participants were faster and more accurate at detecting angry expressions on male faces and at detecting happy expressions on female faces. These findings were robust across different stimulus sets and judgment tasks and indicated bottom-up perceptual processes rather than just top-down conceptually driven ones. Results from additional studies in which neutrally expressive faces were used suggested that the connections between masculine features and angry expressions and between feminine features and happy expressions might be a property of the sexual dimorphism of the face itself and not merely a result of gender stereotypes biasing the perception. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Facial resemblance to emotions: Group differences, impression effects, and race stereotypes.

The authors used connectionist modeling to extend previous research on emotion overgeneralization effects. Study 1 demonstrated that neutral expression male faces objectively resemble angry expressions more than female faces do, female faces objectively resemble surprise expressions more than male faces do, White faces objectively resemble angry expressions more than Black or Korean faces do, and Black faces objectively resemble happy and surprise expressions more than White faces do. Study 2 demonstrated that objective resemblance to emotion expressions influences trait impressions even when statistically controlling possible confounding influences of attractiveness and babyfaceness. It further demonstrated that emotion overgeneralization is moderated by face race and that racial differences in emotion resemblance contribute to White perceivers’ stereotypes of Blacks and Asians. These results suggest that intergroup relations may be strained not only by cultural stereotypes but also by adaptive responses to emotion expressions that are overgeneralized to groups whose faces subtly resemble particular emotions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Attentional capture by irrelevant emotional distractor faces.

We establish attentional capture by emotional distractor faces presented as a “singleton” in a search task in which the emotion is entirely irrelevant. Participants searched for a male (or female) target face among female (or male) faces and indicated whether the target face was tilted to the left or right. The presence (vs. absence) of an irrelevant emotional singleton expression (fearful, angry, or happy) in one of the distractor faces slowed search reaction times compared to the singleton absent or singleton target conditions. Facilitation for emotional singleton targets was found for the happy expression but not for the fearful or angry expressions. These effects were found irrespective of face gender and the failure of a singleton neutral face to capture attention among emotional faces rules out a visual odd-one-out account for the emotional capture. The present study thus establishes irrelevant, emotional, attentional capture. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

The eyebrow frown: A salient social signal.

Seven experiments investigated the finding that threatening schematic faces are detected more quickly than nonthreatening faces. Threatening faces with v-shaped eyebrows (angry and scheming expressions) were detected more quickly than nonthreatening faces with A-shaped eyebrows (happy and sad expressions). In contrast to the hypothesis that these effects were due to perceptual features unrelated to the face, no advantage was found for v-shaped eyebrows presented in a nonfacelike object. Furthermore, the addition of internal facial features (the eyes, or the nose and mouth) was necessary to produce the detection advantage for faces with v-shaped eyebrows. Overall, the results are interpreted as showing that the v-shaped eyebrow configuration affords easy detection, but only when other internal facial features are present. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

When does mimicry affect evaluative judgment?

We investigated the effect of subliminally presented happy or angry faces on evaluative judgments when the facial muscles of participants were free to mimic or blocked. We hypothesized and showed that subliminally presented happy expressions lead to more positive judgments of cartoons compared to angry expressions only when facial muscles were not blocked. These results reveal the influence of socially driven embodied processes on affective judgments and have also potential implications for phenomena such as emotional contagion. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Emotional priming of pop-out in visual search.

When searching for a discrepant target along a simple dimension such as color or shape, repetition of the target feature substantially speeds search, an effect known as feature priming of pop-out (V. Maljkovic and K. Nakayama, 1994). The authors present the first report of emotional priming of pop-out. Participants had to detect the face displaying a discrepant expression of emotion in an array of four face photographs. On each trial, the target when present was either a neutral face among emotional faces (angry in Experiment 1 or happy in Experiment 2), or an emotional face among neutral faces. Target detection was faster when the target displayed the same emotion on successive trials. This effect occurred for angry and for happy faces, not for neutral faces. It was completely abolished when faces were inverted instead of upright, suggesting that emotional categories rather than physical feature properties drive emotional priming of pop-out. The implications of the present findings for theoretical accounts of intertrial priming and for the face-in-the-crowd phenomenon are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Influence of facial expression on memory for facial identity: Effects of visual features or emotional meaning?

Research has shown that neutral faces are better recognized when they had been presented with happy rather than angry expressions at study, suggesting that emotional signals conveyed by facial expressions influenced the encoding of novel facial identities in memory. An alternative explanation, however, would be that the influence of facial expression resulted from differences in the visual features of the expressions employed. In this study, this possibility was tested by manipulating facial expression at study versus test. In line with earlier studies, we found that neutral faces were better recognized when they had been previously encountered with happy rather than angry expressions. On the other hand, when neutral faces were presented at study and participants were later asked to recognize happy or angry faces of the same individuals, no influence of facial expression was detected. As the two experimental conditions involved exactly the same amount of changes in the visual features of the stimuli between study and test, the results cannot be simply explained by differences in the visual properties of different facial expressions and may instead reside in their specific emotional meaning. The findings further suggest that the influence of facial expression is due to disruptive effects of angry expressions rather than facilitative effects of happy expressions. This study thus provides additional evidence that facial identity and facial expression are not processed completely independently. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Looking for Foes and Friends: Perceptual and Emotional Factors When Finding a Face in the Crowd.

In a face-in-the-crowd setting, the authors examined visual search for photographically reproduced happy, angry, and fearful target faces among neutral distractor faces in 3 separate experiments. Contrary to the hypothesis, happy targets were consistently detected more quickly and accurately than angry and fearful targets, as were directed compared with averted targets. There was no consistent effect of social anxiety. A facial emotion recognition experiment suggested that the happy search advantage could be due to the ease of processing happy faces. In the final experiment with perceptually controlled schematic faces, the authors reported more effective detection of angry than happy faces. This angry advantage was most obvious for highly socially anxious individuals when their social fear was experimentally enhanced. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Biased recognition of positive faces in aging and amnestic mild cognitive impairment.

We investigated age differences in biased recognition of happy, neutral, or angry faces in 4 experiments. Experiment 1 revealed increased true and false recognition for happy faces in older adults, which persisted even when changing each face’s emotional expression from study to test in Experiment 2. In Experiment 3, we examined the influence of reduced memory capacity on the positivity-induced recognition bias, which showed the absence of emotion-induced memory enhancement but a preserved recognition bias for positive faces in patients with amnestic mild cognitive impairment compared with older adults with normal memory performance. In Experiment 4, we used semantic differentials to measure the connotations of happy and angry faces. Younger and older participants regarded happy faces as more familiar than angry faces, but the older group showed a larger recognition bias for happy faces. This finding indicates that older adults use a gist-based memory strategy based on a semantic association between positive emotion and familiarity. Moreover, older adults’ judgments of valence were more positive for both angry and happy faces, supporting the hypothesis of socioemotional selectivity. We propose that the positivity-induced recognition bias might be based on fluency, which in turn is based on both positivity-oriented emotional goals and on preexisting semantic associations. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Facial expressions as conditioned stimuli for electrodermal responses: A case of "preparedness"?

Converging data suggest that human facial behavior has an evolutionary basis. Combining these data with M. E. Seligman's (1970) preparedness theory, it was predicted that facial expressions of anger should be more readily associated with aversive events than should expressions of happiness. Two experiments involving differential electrodermal conditioning to pictures of faces, with electric shock as the unconditioned stimulus, were performed. In the 1st experiment, 32 undergraduates were exposed to 2 pictures of the same person, 1 with an angry and 1 with a happy expression. For half of the Ss, the shock followed the angry face, and for the other half, it followed the happy face. In the 2nd experiment, 3 groups of 48 undergraduates differentiated between pictures of male and female faces, both showing angry, neutral, and happy expressions. Responses to angry CSs showed significant resistance to extinction in both experiments, with a larger effect in Exp II. Responses to happy or neutral CSs, on the other hand, extinguished immediately when the shock was withheld. Results are related to conditioning to phobic stimuli and to the preparedness theory. (22 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Does Facial Expression Affect Attention Orienting by Gaze Direction Cues?

In 6 experiments, the authors investigated whether attention orienting by gaze direction is modulated by the emotional expression (neutral, happy, angry, or fearful) on the face. The results showed a clear spatial cuing effect by gaze direction but no effect by facial expression. In addition, it was shown that the cuing effect was stronger with schematic faces than with real faces, that gaze cuing could be achieved at very short stimulus onset asynchronies (14 ms), and that there was no evidence for a difference in the strength of cuing triggered by static gaze cues and by cues involving apparent motion of the pupils. In sum, the results suggest that in normal, healthy adults, eye direction processing for attention shifts is independent of facial expression analysis. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Angry faces are special too: Evidence from the visual scanpath.

Traditional models of face processing posit independent pathways for the processing of facial identity and facial expression (e.g., Bruce & Young, 1986). However, such models have been questioned by recent reports that suggest positive expressions may facilitate recognition (e.g., Baudouin et al., 2000), although little attention has been paid to the role of negative expressions. The current study used eye movement indicators to examine the influence of emotional expression (angry, happy, neutral) on the recognition of famous and novel faces. In line with previous research, the authors found some evidence that only happy expressions facilitate the processing of famous faces. However, the processing of novel faces was enhanced by the presence of an angry expression. Contrary to previous findings, this paper suggests that angry expressions also have an important role in the recognition process, and that the influence of emotional expression is modulated by face familiarity. The implications of this finding are discussed in relation to (1) current models of face processing, and (2) theories of oculomotor control in the viewing of facial stimuli. (PsycINFO Database Record (c) 2010 APA, all rights reserved)