Asymmetric dependencies in perceiving identity and emotion: experiments with morphed faces.

We investigated whether an asymmetric relationship between the perception of identity and emotional expressions in faces (Schweinberger & Soukup, 1998) may be related to differences in the relative processing speed of identity and expression information. Stimulus faces were morphed across identity within a given emotional expression, or were morphed across emotion within a given identity. In Experiment 1, consistent classifications of these images were demonstrated across a wide range of morphing, with only a relatively narrow category boundary. At the same time, classification reaction times (RTs) reflected the increased perceptual difficulty of the morphed images. In Experiment 2, we investigated the effects of variations in the irrelevant dimension on judgments of faces with respect to a relevant dimension, using a Garner-type speeded classification task. RTs for expression classifications were strongly influenced by irrelevant identity information. In contrast, RTs for identity classifications were unaffected by irrelevant expression information, and this held even for stimuli in which identity was more difficult and slower to discriminate than expression. This suggests that differences in processing speed cannot account for the asymmetric relationship between identity and emotion perception. Theoretical accounts proposing independence of identity and emotion perception are discussed in the light of these findings.     

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.     

Conscious and nonconscious discrimination of facial expressions

Abrupt discontinuities in recognizing categories of emotion are found for the labelling of consciously perceived facial expressions. This has been taken to imply that, at a conscious level, we perceive facial expressions categorically. We investigated whether the abrupt discontinuities found in categorization for conscious recognition would be replaced by a graded transition for subthreshold stimuli. Fifteen volunteers participated in two experiments, in which participants viewed faces morphed from 100% fear to 100% disgust along seven increments. In Experiment A, target faces were presented for 30 ms, in Experiment B for 170 ms. Participants made two-alternative forced-choice decisions between fear and disgust. Results for the 30 ms presentation time indicated a significant linear trend between degree of morphing and classification of the images. Results for 170 ms presentation time followed the higher order function found in studies of categorical perception. These results provide preliminary evidence for separate processes underlying conscious and nonconscious perception of facial expressions of emotion.     

Emotion recognition: The role of featural and configural face information

Several studies investigated the role of featural and configural information when processing facial identity. A lot less is known about their contribution to emotion recognition. In this study, we addressed this issue by inducing either a featural or a configural processing strategy (Experiment 1) and by investigating the attentional strategies in response to emotional expressions (Experiment 2). In Experiment 1, participants identified emotional expressions in faces that were presented in three different versions (intact, blurred, and scrambled) and in two orientations (upright and inverted). Blurred faces contain mainly configural information, and scrambled faces contain mainly featural information. Inversion is known to selectively hinder configural processing. Analyses of the discriminability measure (A′) and response times (RTs) revealed that configural processing plays a more prominent role in expression recognition than featural processing, but their relative contribution varies depending on the emotion. In Experiment 2, we qualified these differences between emotions by investigating the relative importance of specific features by means of eye movements. Participants had to match intact expressions with the emotional cues that preceded the stimulus. The analysis of eye movements confirmed that the recognition of different emotions rely on different types of information. While the mouth is important for the detection of happiness and fear, the eyes are more relevant for anger, fear, and sadness.     

Dominance of texture over shape in facial identity processing is modulated by individual abilities

For face recognition, observers utilize both shape and texture information. Here, we investigated the relative diagnosticity of shape and texture for delayed matching of familiar and unfamiliar faces (Experiment 1) and identifying familiar and newly learned faces (Experiment 2). Within each familiarity condition, pairs of 3D‐captured faces were morphed selectively in either shape or texture in 20% steps, holding the respective other dimension constant. We also assessed participants’ individual face‐processing skills via the Bielefelder Famous Faces Test (BFFT), the Glasgow Face Matching Test, and the Cambridge Face Memory Test (CFMT). Using multilevel model analyses, we examined probabilities of same versus different responses (Experiment 1) and of original identity versus other/unknown identity responses (Experiment 2). Overall, texture was more diagnostic than shape for both delayed matching and identification, particularly so for familiar faces. On top of these overall effects, above‐average BFFT performance was associated with enhanced utilization of texture in both experiments. Furthermore, above‐average CFMT performance coincided with slightly reduced texture dominance in the delayed matching task (Experiment 1) and stronger sensitivity to morph‐based changes overall, that is irrespective of morph type, in the face identification task (Experiment 2). Our findings (1) show the disproportionate importance of texture information for processing familiar face identity and (2) provide further evidence that familiar and unfamiliar face identity perception are mediated by different underlying processes.     

Interactions between facial emotion and identity in face processing: Evidence based on redundancy gains

Interactions between the processing of emotion expression and form-based information from faces (facial identity) were investigated using the redundant-target paradigm, in which we specifically tested whether identity and emotional expression are integrated in a superadditive manner (Miller, Cognitive Psychology 14:247?C279, 1982). In Experiments 1 and 2, participants performed emotion and face identity judgments on faces with sad or angry emotional expressions. Responses to redundant targets were faster than responses to either single target when a universal emotion was conveyed, and performance violated the predictions from a model assuming independent processing of emotion and face identity. Experiment 4 showed that these effects were not modulated by varying interstimulus and nontarget contingencies, and Experiment 5 demonstrated that the redundancy gains were eliminated when faces were inverted. Taken together, these results suggest that the identification of emotion and facial identity interact in face processing.     

Visual adaptation of the perception of “life”: Animacy is a basic perceptual dimension of faces

One critical component of understanding another’s mind is the perception of “life” in a face. However, little is known about the cognitive and neural mechanisms underlying this perception of animacy. Here, using a visual adaptation paradigm, we ask whether face animacy is (1) a basic dimension of face perception and (2) supported by a common neural mechanism across distinct face categories defined by age and species. Observers rated the perceived animacy of adult human faces before and after adaptation to (1) adult faces, (2) child faces, and (3) dog faces. When testing the perception of animacy in human faces, we found significant adaptation to both adult and child faces, but not dog faces. We did, however, find significant adaptation when morphed dog images and dog adaptors were used. Thus, animacy perception in faces appears to be a basic dimension of face perception that is species specific but not constrained by age categories.     

Depression impairs the ability to ignore the emotional aspects of facial expressions: Evidence from the Garner task

We assessed dysphoric and clinically distressed individuals' ability to ignore the emotional aspects of facial expressions using the Garner speeded‐classification task. Garner's paradigm tests the ability to selectively focus on a single relevant dimension while ignoring variations on other, irrelevant, ones. In the present task, the stimuli were faces of men and women expressing happy, angry, and neutral emotions. In Experiments 1 and 2, dysphoric and nondysphoric participants performed the Garner task, focusing on gender and ignoring emotion (Experiment 1) and focusing on emotion and ignoring gender (Experiment 2). Results suggest that dysphoric individuals exhibited more difficulty ignoring the emotional dimension of social stimuli even under specific instructions to do so than nondysphoric individuals. In Experiments 3 and 4, we replicated these results in clinically distressed and nondistressed individuals. The results of Experiment 3 further suggested that depression was more closely associated with the inability to selectively ignore emotion than was social anxiety. Experiment 4 confirmed that this failure of selective attention was specific to processing emotional, and not gender features. The implications of these findings for cognitive and interpersonal theories of depression are discussed.     

面孔熟悉度对面孔性别与表情相互作用的调节

对于面孔性别与表情的关系, 目前的理论尚不完善。而众多研究证据表明, 面孔熟悉度与面孔性别及表情的加工均有密切关系。本研究基于Garner范式考察了在不同面孔熟悉度下面孔性别与表情的相互关系。共包括4项实验：实验1, 面孔刺激的身份陌生且不重复, 刺激在Garner范式的控制组和正交组中均仅呈现一次, 面孔熟悉度低; 实验2, 除面孔刺激的身份重复外, 其余均同实验1, 面孔熟悉度中等; 实验3, 面孔刺激的身份陌生且不重复, 但分别在控制组和正交组中重复呈现多次, 面孔熟悉度高; 实验4, 通过面孔学习增加面孔的熟悉度, 以直接验证面孔熟悉度的增加对面孔性别与表情相互关系的影响。结果发现：对于陌生面孔, 表情单向影响面孔性别的加工; 随着面孔熟悉度的增加, 面孔性别与表情之间出现双向的影响。因此, 面孔熟悉度对面孔性别与表情的相互影响具有调节作用。     

Threat advantage: Perception of angry and happy dynamic faces across cultures

The current study tested whether the perception of angry faces is cross-culturally privileged over that of happy faces, by comparing perception of the offset of emotion in a dynamic flow of expressions. Thirty Chinese and 30 European-American participants saw movies that morphed an anger expression into a happy expression of the same stimulus person, or vice versa. Participants were asked to stop the movie at the point where they ceased seeing the initial emotion. As expected, participants cross-culturally continued to perceive anger longer than happiness. Moreover, anger was perceived longer in in-group than in out-group faces. The effects were driven by female rather than male targets. Results are discussed with reference to the important role of context in emotion perception.     

Threat advantage: Perception of angry and happy dynamic faces across cultures

The current study tested whether the perception of angry faces is cross-culturally privileged over that of happy faces, by comparing perception of the offset of emotion in a dynamic flow of expressions. Thirty Chinese and 30 European-American participants saw movies that morphed an anger expression into a happy expression of the same stimulus person, or vice versa. Participants were asked to stop the movie at the point where they ceased seeing the initial emotion. As expected, participants cross-culturally continued to perceive anger longer than happiness. Moreover, anger was perceived longer in in-group than in out-group faces. The effects were driven by female rather than male targets. Results are discussed with reference to the important role of context in emotion perception.     

Facial identity and facial expression matching in 5–12‐year‐old children and adults

Facial identity and facial expression matching tasks were completed by 5–12‐year‐old children and adults using stimuli extracted from the same set of normalized faces. Configural and feature processing were examined using speed and accuracy of responding and facial feature selection, respectively. Facial identity matching was slower than face expression matching for all age groups. Large age effects were found on both speed and accuracy of responding and feature use in both identity and expression matching tasks. Eye region preference was found on the facial identity task and mouth region preference on the facial expression task. Use of mouth region information for facial expression matching increased with age, whereas use of eye region information for facial identity matching peaked early. The feature use information suggests that the specific use of primary facial features to arrive at identity and emotion matching judgments matures across middle childhood. Copyright © 2009 John Wiley & Sons, Ltd.     

Symmetrical interaction of sex and expression in face classification tasks

Classification of faces as to their sex or their expression—with sex and expression varying orthogonally—was studied in three experiments. In Experiment 1, expression classification was influenced by sex, with angry male faces being classified faster than angry female faces. Complementarily, sex classification was faster for happy than for angry female faces. In Experiment 2, mutual interaction of sex and expression was also found when the participants were asked to classify top and bottom face segments. In Experiment 3, a face inversion effect was found for both sex and expression classification of whole faces. However, a symmetrical interaction between sex and expression was again found. The results are discussed in terms of configural versus feature processing in the perception of face sex and expression and of their relevance to face perception models that postulate independent processing of different facial features. 2009 The Psychonomic Society, Inc.     

Differences in holistic processing do not explain cultural differences in the recognition of facial expression

The aim of this study was to investigate the causes of the own-race advantage in facial expression perception. In Experiment 1, we investigated Western Caucasian and Chinese participants’ perception and categorization of facial expressions of six basic emotions that included two pairs of confusable expressions (fear and surprise; anger and disgust). People were slightly better at identifying facial expressions posed by own-race members (mainly in anger and disgust). In Experiment 2, we asked whether the own-race advantage was due to differences in the holistic processing of facial expressions. Participants viewed composite faces in which the upper part of one expression was combined with the lower part of a different expression. The upper and lower parts of the composite faces were either aligned or misaligned. Both Chinese and Caucasian participants were better at identifying the facial expressions from the misaligned images, showing interference on recognizing the parts of the expressions created by holistic perception of the aligned composite images. However, this interference from holistic processing was equivalent across expressions of own-race and other-race faces in both groups of participants. Whilst the own-race advantage in recognizing facial expressions does seem to reflect the confusability of certain emotions, it cannot be explained by differences in holistic processing.     

Evaluating the independence of sex and expression in judgments of faces

Face recognition models suggest independent processing for functionally different types of information, such as identity, expression, sex, and facial speech. Interference between sex and expression information was tested using both a rating study and Garner's selective attention paradigm using speeded sex and expression decisions. When participants were asked to assess the masculinity of male and female angry and surprised faces, they found surprised faces to be more feminine than angry ones (Experiment 1). However, in a speeded-classification situation in the laboratory in which the sex decision was either "easy" relative to the expression decision (Experiment 2) or of more equivalent difficulty (Experiment 3), it was possible for participants to attend selectively to either dimension without interference from the other. Qualified support is offered for independent processing routes.     

知觉经验对面孔整体加工的影响

基于经验的整体加工理论认为, 随着知觉经验的增多, 人们加工面孔的专家化能力逐渐增强。其中一种表现形式为, 在知觉面孔时更倾向于整体加工。该理论已经得到了一些实验证据的支持, 但未能解释另外一些研究的发现, 即对他族人群没有长期知觉经验的被试在加工他族面孔时也有强烈的整体加工。本研究旨在考察知觉经验对面孔整体加工的影响, 包括两个实验。实验1a通过组合面孔范式测量了中国被试在辨别本族面孔、他族面孔和种族融合面孔时的组合面孔效应(即面孔整体加工强度)。结果发现, 被试在知觉种族融合面孔时没有表现出组合面孔效应, 在知觉本族面孔和他族面孔时都表现出强烈的组合面孔效应。实验1b以灰阶图重复了实验1a。结果发现, 被试在知觉种族融合面孔时仍然没有表现出组合面孔效应, 在知觉本族面孔和他族面孔时表现出强烈的组合面孔效应。实验2通过操纵种族融合面孔的有或无, 测量5 s的知觉经验对融合面孔的组合效应的影响。结果发现, 在经过短时的知觉经验后, 被试在知觉融合面孔时也表现出强烈的组合面孔效应。上述实验结果表明, 中国被试在加工本族面孔、他族面孔和种族融合面孔时所诱发组合面孔效应有显著的、量的差别, 且这种整体加工的差异不会受到面孔肤色信息的影响。在经过短时的知觉经验后, 中国被试在加工种族融合面孔时表现出强烈的整体加工。该研究的发现提示, 不论是短时知觉经验还是长期知觉经验, 知觉经验的增加是面孔整体加工的一个关键要素。     

Perceptual awareness and categorical representation of faces: evidence from masked priming

How internal categories influence how we perceive the world is a fundamental question in cognitive sciences. Yet, the relation between perceptual awareness and perceptual categorization has remained largely uncovered so far. Here, we addressed this question by focusing on face perception during subliminal and conscious perception. We used morphed continua between two face identities and we assessed, through a masked priming paradigm, the perceptual processing of these morphed faces under subliminal and supraliminal conditions. We found that priming from subliminal faces followed linearly the information present in the primes, while priming from visible faces revealed a non-linear profile, indicating a categorical processing of face identities. Our results thus point to a special relation between perceptual awareness and categorical processing of faces, and support the dissociation between two modes of information processing: a subliminal mode involving analog treatment of stimuli information, and a supraliminal mode relying on discrete representation.     

Effects of familiarity on the perceptual integrality of the identity and expression of faces: the parallel-route hypothesis revisited

The effects of familiarity on selective attention for the identity and expression of faces were tested using Garner's speeded-classification task. In 2 experiments, participants classified expression (or identity) of familiar and unfamiliar faces while the irrelevant dimension of identity (or expression) was either held constant (baseline condition) or varied randomly (filtering condition). Selective attention was measured by the difference in performance between these 2 conditions. Failure of selective attention was larger for familiar than for unfamiliar faces. In addition, failure of selective attention was found both for identity and for expression judgments. These findings show that familiarity increases (he perceptual integrality between identity and expression, and they question previous studies arguing that identity judgments are always resistant to irrelevant variations in expression. The authors suggest that the systems processing identity and expression are interconnected in that facial identity serves as a reference from which expressions can be more easily derived.     

Dimensional interactions in language processing: investigating directions and levels of crosstalk

In this article we evaluate current models of language processing by testing speeded classification of stimuli comprising one linguistic and one nonlinguistic dimension. Garner interference obtains if subjects are slower to classify attributes on one dimension when an irrelevant dimension is varied orthogonally than when the irrelevant dimension is held constant. With certain linguistic-nonlinguistic pairings (e.g., Experiment 1: the words high and low spoken either loudly or softly), significant Garner interference obtained when either dimension was classified; this indicated two-directional crosstalk. With other pairings (e.g., Experiment 3: spoken vowels and loudness), only the nonlinguistic dimension (e.g., loudness) displayed interference, suggesting unidirectional crosstalk downstream from a phonemic/graphemic level of analysis. Collectively, these results indicate the interaction can occur either within or across levels of information processing, being directed toward either more advanced or more primitive processes. Although poorly explained by all current models of language processing, our results are strikingly inconsistent with models that posit autonomy among levels of processing.