On the interplay between familiarity and emotional expression in face perception

Traditional models of face perception (e.g. Bruce and Young 1986) stress independent routes for processing identity and emotional expression. We investigated the interplay between familiarity and emotional expression by systematically varying both factors. In contrast to earlier studies which used binary forced-choice decisions, participants had to judge the familiarity of the presented face and the emotional hedonic valence and emotional arousal of its expressed emotion (angry, happy or neutral), using rating scales. The results demonstrated symmetric, strong interactions between familiarity and expressed emotion. Thus, this study supports more recent models of face perception (Haxby et al. 2000) that were mostly based on brain imaging data. These data together with our behavioural results emphasize the interaction of emotional expression and personal identity and support approaches that propose a relative segregation of these processes, rather than completely independent coding (Calder and Young 2005).     

情绪概念加工与情绪面孔知觉的相互影响

通过3个实验探讨情绪概念加工与情绪面孔知觉是否存在相互影响, 以及加工深度对两者关系的影响。实验1采用情绪面孔启动范式, 探讨较深的情绪概念加工层面对情绪概念与情绪面孔的关系的影响。实验2更改概念任务, 探讨较浅的概念加工层面对两者关系的影响。实验3缩短启动面孔呈现时间, 探讨较浅的面孔知觉层面对两者关系的影响。通过研究主要得出以下结论：(1)情绪概念加工与情绪面孔知觉确实存在相互影响; (2)概念加工深度影响两者关系的方向性, 在较深的概念加工层面, 两者的关系是双向的, 在较浅的概念加工层面, 两者的关系是单向的; (3)知觉加工深度也影响两者关系的方向性, 在较深的知觉加工层面, 两者的关系是双向的, 在较浅的知觉加工层面, 没有发现两者的相互影响。本研究为抽象概念的具身表征提供了实证支持。     

Asymmetric interference between sex and emotion in face perception

Previous research with speeded-response interference tasks modeled on the Garner paradigm has demonstrated that task-irrelevant variations in either emotional expression or facial speech do not interfere with identity judgments, but irrelevant variations in identity do interfere with expression and facial speech judgments. Sex, like identity, is a relatively invariant aspect of faces. Drawing on a recent model of face processing according to which invariant and changeable aspects of faces are represented in separate neurological systems, we predicted asymmetric interference between sex and emotion classification. The results of Experiment 1, in which the Garner paradigm was employed, confirmed this prediction: Emotion classifications were influenced by the sex of the faces, but sex classifications remained relatively unaffected by facial expression. A second experiment, in which the difficulty of the tasks was equated, corroborated these findings, indicating that differences in processing speed cannot account for the asymmetric relationship between facial emotion and sex processing. A third experiment revealed the same pattern of asymmetric interference through the use of a variant of the Simon paradigm. To the extent that Garner interference and Simon interference indicate interactions at perceptual and response-selection stages of processing, respectively, a challenge for face processing models is to show how the same asymmetric pattern of interference could occur at these different stages. The implications of these findings for the functional independence of the different components of face processing are discussed.     

The development of emotional face and eye gaze processing

Recent research has demonstrated that infants' attention towards novel objects is affected by an adult's emotional expression and eye gaze toward the object. The current event-related potential (ERP) study investigated how infants at 3, 6, and 9 months of age process fearful compared to neutral faces looking toward objects or averting gaze away from objects. Furthermore, we examined how the processing of novel objects is affected by gaze direction and emotional expression. We hypothesized that an adult's fearful expression should be particularly salient when it is directed toward a referent in the environment. Furthermore, responses to objects should be increased if the face previously expressed fear toward the object. Three-month-olds did not show differential neural responses to fearful vs. neutral faces regardless of gaze direction. Six-month-olds showed an enhanced negative central (Nc) component for fearful relative to neutral faces looking toward objects, but not when eye gaze was averted away from the objects. Furthermore, 6-month-olds showed an enhanced Nc for objects that had been gaze-cued by a fearful compared to a neutral face. Nine-month-olds showed an enhanced Nc for fearful relative to neutral faces in both eye gaze conditions and showed an enhanced Nc for objects that had been gaze-cued by a neutral face. The findings are discussed in the context of social cognitive and brain development.     

Garner interference and temporal information processing

The aim of the study was to explore whether temporal information processing can interfere with performance of a non-temporal task. A new methodology based on the Garner paradigm was employed. Participants were asked to classify two-dimensional stimuli according to either length or duration, with and without variation in the other (task-irrelevant) dimension. Garner interference was detected only with respect to classification by length when irrelevant variation in duration was present. Stroop interference was detected only in classification by length across compatible and non-compatible values of length and duration. Classification by length took more time when done with variation in duration than when duration was constant. Classification by length also took more time when length and duration were not compatible than when they were compatible. The findings indicate that the processing of duration is similar to the processing of other perceptual dimensions. The processing of duration consumes attentional resources and can interfere with the processing of other perceptual dimensions. The findings support attentional models of prospective duration judgment.     

Emotional expression affects the accuracy of gaze perception

Emotional facial expressions are powerful social cues. Here we investigated how emotional expression affects the interpretation of eye gaze direction. Fifty-two observers judged where faces were looking by moving a slider on a measuring bar to the respective position. The faces displayed either an angry, happy, fearful or a neutral expression and were looking either straight at the observer, or were rotated 2°, 4°, 6° or 8° to the left and right. We found that happy faces were interpreted as directed closer to the observer, while fearful and angry faces were interpreted as directed further away. Judgments were most accurate for neutral faces, followed by happy, angry and fearful faces. These findings are discussed on the background of the “self-referential positivity bias”, suggesting that happy faces are preferably interpreted as directed towards the self while negative emotions are interpreted as directed further away.     

Eastern observers cannot inhibit their gaze to eye and nose regions in face perception

It has been found that Western observers cannot inhibit their gaze to the eye region, even if they are told to avoid doing so when they observe face stimuli because of the importance of the eye region. However, studies indicate that the nose region is more important for face processing among Eastern observers. We used the “don’t look” paradigm with Eastern observers, in which participants were told to avoid fixating on a specific region (eye, nose, and mouth). The results extend previous findings as both the eye and nose regions attracted their gaze. Interestingly, the fixation behaviors differed for the eyes and nose in terms of the time-dependent view, in which reflexive saccades to the eye with a persistent fixation to the nose were observed. The nose regions could have stronger attractiveness than previously thought.     

A direct link between gaze perception and social attention

How information is exchanged between the cognitive mechanisms responsible for gaze perception and social attention is unclear. These systems could be independent; the "gaze cueing" effect could emerge from the activation of a general-purpose attentional mechanism that is ignorant of the social nature of the gaze cue. Alternatively, orienting to social gaze direction might be directly determined by the operation of cognitive mechanisms specifically dedicated to gaze perception. This second notion is the dominant assumption in the literature, but there is little direct support for this account. Here, we systematically manipulated observers' perception of gaze direction by implementing a gaze adaptation paradigm. Gaze cueing was reduced only in conditions where perception of specific averted gaze stimuli was impaired (Experiment 1). Adaptation to a pointing stimulus failed to impact gaze cueing (Experiment 2). Overall, these data suggest a direct link between the specific operation of gaze perception mechanisms and the consequential orienting of attention.     

Infants' ability to connect gaze and emotional expression to intentional action

Four studies investigated whether and when infants connect information about an actor's affect and perception to their action. Arguably, this may be a crucial way in which infants come to recognize the intentional behaviors of others. In Study 1 an actor grasped one of two objects in a situation where cues from the actor's gaze and expression could serve to determine which object would be grasped, specifically the actor first looked at and emoted positively about one object but not the other. Twelve-month-olds, but not 8-month-olds, recognized that the actor was likely to grasp the object which she had visually regarded with positive affect. Studies 2, 3, and 4 replicated the main finding from Study 1 with 12- and 14-month-olds and included several contrasting conditions and controls. These studies provide evidence that the ability to use information about an adult's direction of gaze and emotional expression to predict action is both present, and developing at the end of the first year of life.     

Influence of emotional expression on the processing of gaze direction

Research demonstrates an influence of gaze direction in emotion recognition. Here we examined whether facial affect similarly influences recognition of gaze direction. Across two studies we found that averted relative to direct gaze was processed more quickly and accurately when coupled with fear, and direct relative to averted gaze with anger. Also evident was that slower overall gaze processing was associated with increased interaction effects between emotion and gaze. Examining individual differences, therefore, enabled us to extend previous research examining speed of processing as a moderator of the interaction effect, while holding constant task demands and stimulus features. Unexpectedly, a main effect emerged such that averted relative to direct gaze was found to be processed more quickly and accurately overall. This effect was not moderated by processing speed and is discussed as a potential stimulus-driven effect that may help explain discrepant findings in the literature.

Spatial interference between gaze direction and gaze location: A study on the eye contact effect

Perceived gaze in faces is an important social cue that influences spatial orienting of attention. In three experiments, we examined whether the social relevance of gaze direction modulated spatial interference in response selection, using three different stimuli: faces, isolated eyes, and symbolic eyes (Experiments 1, 2, and 3, respectively). Each experiment employed a variant of the spatial Stroop paradigm in which face location and gaze direction were put into conflict. Results showed a reverse congruency effect between face location to the right or left of fixation and gaze direction only for stimuli with a social meaning to participants (Experiments 1 and 2). The opposite was observed for the nonsocial stimuli used in Experiment 3. Results are explained as facilitation in response to eye contact.     

Spatial interference between gaze direction and gaze location: a study on the eye contact effect

Perceived gaze in faces is an important social cue that influences spatial orienting of attention. In three experiments, we examined whether the social relevance of gaze direction modulated spatial interference in response selection, using three different stimuli: faces, isolated eyes, and symbolic eyes (Experiments 1, 2, and 3, respectively). Each experiment employed a variant of the spatial Stroop paradigm in which face location and gaze direction were put into conflict. Results showed a reverse congruency effect between face location to the right or left of fixation and gaze direction only for stimuli with a social meaning to participants (Experiments 1 and 2). The opposite was observed for the nonsocial stimuli used in Experiment 3. Results are explained as facilitation in response to eye contact.     

Stimulus variability and processing dependencies in speech perception

Processing dependencies in speech perception between voice and phoneme were investigated using the Garner (1974) speeded classification procedure. Variability in the voice of the talker and in the cues to word-initial consonants were manipulated. The results showed that the processing of a talker's voice and the perception of voicing are asymmetrically dependent. In addition, when stimulus variability was increased in each dimension, the amount of orthogonal interference obtained for each dimension became significantly larger. The processing asymmetry between voice and phoneme was interpreted in terms of a parallel-contingent relationship of talker normalization processes to auditory-to-phonetic coding processes. The processing of voice information appears to be qualitatively different from the encoding of segmental phonetic information, although they are not independent. Implications of these results for current theories of speech perception are discussed.     

The relationships between processing facial identity,emotional expression,facial speech,and gaze direction during development

Four experiments were conducted with 5- to 11-year-olds and adults to investigate whether facial identity, facial speech, emotional expression, and gaze direction are processed independently of or in interaction with one another. In a computer-based, speeded sorting task, participants sorted faces according to facial identity while disregarding facial speech, emotional expression, and gaze direction or, alternatively, according to facial speech, emotional expression, and gaze direction while disregarding facial identity. Reaction times showed that children and adults were able to direct their attention selectively to facial identity despite variations of other kinds of face information, but when sorting according to facial speech and emotional expression, they were unable to ignore facial identity. In contrast, gaze direction could be processed independently of facial identity in all age groups. Apart from shorter reaction times and fewer classification errors, no substantial change in processing facial information was found to be correlated with age. We conclude that adult-like face processing routes are employed from 5 years of age onward.     

Developmental course of auditory processing interactions: Garner interference and Simon interference.

Previous research suggests that with increasing age children become more efficient in inhibiting conflicting responses and in resisting interference from irrelevant information. We assessed the abilities of 100 children (ages 3-16 years) and 20 adults to resist interference during the processing of 2 auditory dimensions of speech, namely the speaker's gender and spatial location. The degree of interference from irrelevant variability in either dimension did not vary with age. Apparently, young children do not have more difficulty in resisting interference when the nontarget and the target are both perceptual attributes. We also assessed the participants' abilities to inhibit conflicting task-irrelevant information from spatial location and to resist interference from spatial variability in the context of conflict. In the presence of conflicting task-irrelevant information, both interference effects declined significantly with age. Developmental change in auditory processing seems to vary as a function of (1) the nature of the target-nontarget combination and (2) the presence/absence of conflicting task-irrelevant information.     

Affective evaluations of objects are influenced by observed gaze direction and emotional expression

Gaze direction signals another person's focus of interest. Facial expressions convey information about their mental state. Appropriate responses to these signals should reflect their combined influence, yet current evidence suggests that gaze-cueing effects for objects near an observed face are not modulated by its emotional expression. Here, we extend the investigation of perceived gaze direction and emotional expression by considering their combined influence on affective judgments. While traditional response-time measures revealed equal gaze-cueing effects for happy and disgust faces, affective evaluations critically depended on the combined product of gaze and emotion. Target objects looked at with a happy expression were liked more than objects looked at with a disgust expression. Objects not looked at were rated equally for both expressions. Our results demonstrate that facial expression does modulate the way that observers utilize gaze cues: Objects attended by others are evaluated according to the valence of their facial expression.     

On the relationship between memory and perception: sequential dependencies in recognition memory testing

Many models of recognition are derived from models originally applied to perception tasks, which assume that decisions from trial to trial are independent. While the independence assumption is violated for many perception tasks, we present the results of several experiments intended to relate memory and perception by exploring sequential dependencies in recognition. The findings from these experiments disconfirm the independence assumption for recognition memory. In addition, the pattern of sequential dependencies observed in recognition differs from that observed for many perception tasks. This suggests that sequential dependencies arise from mnemonic or perceptual processes and not from decision processes that should be common to memory and perception tasks.     

Mutual interference between statistical summary perception and statistical learning

The visual system is an efficient statistician, extracting statistical summaries over sets of objects (statistical summary perception) and statistical regularities among individual objects (statistical learning). Although these two kinds of statistical processing have been studied extensively in isolation, their relationship is not yet understood. We first examined how statistical summary perception influences statistical learning by manipulating the task that participants performed over sets of objects containing statistical regularities (Experiment 1). Participants who performed a summary task showed no statistical learning of the regularities, whereas those who performed control tasks showed robust learning. We then examined how statistical learning influences statistical summary perception by manipulating whether the sets being summarized contained regularities (Experiment 2) and whether such regularities had already been learned (Experiment 3). The accuracy of summary judgments improved when regularities were removed and when learning had occurred in advance. In sum, calculating summary statistics impeded statistical learning, and extracting statistical regularities impeded statistical summary perception. This mutual interference suggests that statistical summary perception and statistical learning are fundamentally related.