Integration of internal and external facial features in 8- to 10-year-old children and adults

Investigation of whole-part and composite effects in 4- to 6-year-old children gave rise to claims that face perception is fully mature within the first decade of life (Crookes & McKone, 2009). However, only internal features were tested, and the role of external features was not addressed, although external features are highly relevant for holistic face perception (Sinha & Poggio, 1996; Axelrod & Yovel, 2010, 2011). In this study, 8- to 10-year-old children and adults performed a same–different matching task with faces and watches. In this task participants attended to either internal or external features. Holistic face perception was tested using a congruency paradigm, in which face and non-face stimuli either agreed or disagreed in both features (congruent contexts) or just in the attended ones (incongruent contexts). In both age groups, pronounced context congruency and inversion effects were found for faces, but not for watches. These findings indicate holistic feature integration for faces. While inversion effects were highly similar in both age groups, context congruency effects were stronger for children. Moreover, children's face matching performance was generally better when attending to external compared to internal features. Adults tended to perform better when attending to internal features. Our results indicate that both adults and 8- to 10-year-old children integrate external and internal facial features into holistic face representations. However, in children's face representations external features are much more relevant. These findings suggest that face perception is holistic but still not adult-like at the end of the first decade of life.     

Developmental emergence of holistic processing in word recognition

Holistic processing (HP) of faces refers to the obligatory, simultaneous processing of the parts and their relations, and it emerges over the course of development. HP is manifest in a decrement in the perception of inverted versus upright faces and a reduction in face processing ability when the relations between parts are perturbed. Here, adopting the HP framework for faces, we examined the developmental emergence of HP in another domain for which human adults have expertise, namely, visual word processing. Children, adolescents, and adults performed a lexical decision task and we used two established signatures of HP for faces: the advantage in perception of upright over inverted words and nonwords and the reduced sensitivity to increasing parts (word length). Relative to the other groups, children showed less of an advantage for upright versus inverted trials and lexical decision was more affected by increasing word length. Performance on these HP indices was strongly associated with age and with reading proficiency. Also, the emergence of HP for word perception was not simply a result of improved visual perception over the course of development as no group differences were observed on an object decision task. These results reveal the developmental emergence of HP for orthographic input, and reflect a further instance of experience-dependent tuning of visual perception. These results also add to existing findings on the commonalities of mechanisms of word and face recognition.

Research Highlights

• Children showed less of an advantage for upright versus inverted trials compared to adolescents and adults.
• Relative to the other groups, lexical decision in children was more affected by increasing word length.
• Performance on holistic processing (HP) indices was strongly associated with age and with reading proficiency.
• HP emergence for word perception was not due to improved visual perception over development as there were no group differences on an object decision task.

     

The role of inner and outer face parts in holistic processing: A developmental study

The effects of inner–outer feature interactions with unfamiliar faces were investigated in 6- and 10-year-old children and adults (20–30 years) to determine their contribution in holistic face vision. Participants completed a two-alternative forced-choice (2AFC) task under two conditions. The congruent condition used whole, inner-only, and outer-only stimuli. The incongruent condition used stimuli combining the inner features from one face with outer features from a novel face, or vice versa. Results yielded strong congruency effects which were moderated by pronounced feature-type asymmetries specific to developmental stage. Adults showed an inner-feature preference during congruent trials, but no asymmetry for incongruent trials. Children showed no asymmetry for congruent trials, but an outer-feature preference for incongruent trials. These findings concur with recent theoretical developments indicating that adults and children are likely to differ in the types of feature-specific information they preferentially encode in face perception, and that holistic effects are moderated differently in adults and children as a function of feature type.     

情境对面孔表情识别的影响

长期以来,关于面孔表情识别的研究主要是围绕着面孔本身的结构特征来进行的,但是近年来的研究发现,面孔表情的识别也会受到其所在的情境背景（如语言文字、身体背景、自然与社会场景等）的影响,特别是在识别表情相似的面孔时,情境对面孔表情识别的影响更大。本文首先介绍和分析了近几年关于语言文字、身体动作、自然场景和社会场景等情境影响个体对面孔表情的识别的有关研究;其次,又分析了文化背景、年龄以及焦虑程度等因素对面孔表情识别情境效应的影响;最后,强调了未来的研究应重视研究儿童被试群体、拓展情绪的类别、关注真实生活中的面孔情绪感知等。     

The face behind the mask: a developmental study

Faces are a rich and available source of social information, and the representation for faces is robust in adults (i.e. the face detection effect; Purcell & Stewart, 1988). The current study compared the developmental trajectory of the robustness of face perception against the trajectory for a non-face object. Participants (5-35 years old) were presented with rapid (17 and 33 millisecond) presentations of face and house stimuli and were instructed to identify the object category of the stimulus (face or house). There was an interaction between object type and age such that the developmental slope for face identification was steeper than the slope for house identification for the 17-millisecond presentation. These data show that faces are processed in a different way than a non-face object during the period from middle childhood through adolescence and adulthood, and this differential processing may involve the massive amount of exposure we have to faces.     

成人与幼儿面部表情注意偏好的眼动研究

本研究选取45名3-5岁幼儿和39名大学本科生作为被试。实验材料为恐惧、愤怒、悲伤、惊讶和高兴五种面部表情图片。用Tobbi眼动仪记录被试观察表情图片时的眼动轨迹。结果发现：（1）成人偏好高兴表情,并在高兴表情上的注视时间和次数显著大于幼儿;（2）成人偏好注视眼部,幼儿偏好注视嘴部。结果表明,面部表情注意偏好的发展具有社会依存性,趋向于偏好积极情绪,这种发展变化与面部表情部位的注意偏好相关。     

Gaze detection and the cortical processing of faces: Evidence from infants and adults

Abstract

Faces, as a class of objects, have been studied extensively in order to understand how the human visual system recognizes and represents objects. In this paper we studied the ontogeny of the ability to perceive gaze direction. We bring together both developmental research and neurophysiological and neuropsychological research in order to address this issue. In two experiments we explored the developmental time course of the ability to discriminate between direct and averted gaze, a task thought to involve cortical information processing of faces. We found that (a) infants as young as four months could discriminate between direct and averted gaze, (b) this ability was not due to the development of low-level visual processes, and (c) younger infants did not show reliable evidence of gaze discrimination. In an additional experiment we tested adults to study the effect of face context on the ability to discriminate gaze direction. Adult subjects were more sensitive in this discrimination when the eyes were in the context of an upright face than when the eyes were in either an inverted face or in a scrambled face. Taken together, these results suggest that the mechanisms underlying gaze detection may be mediated by cortical circuits also involved in other aspects of face recognition.     

The composite face illusion

Few findings in cognitive science have proved as influential as the composite face effect. When the top half of one face is aligned with the bottom half of another, and presented upright, the resulting composite arrangement induces a compelling percept of a novel facial configuration. Findings obtained using composite face procedures have contributed significantly to our understanding of holistic face processing, the detrimental effects of face inversion, the development of face perception, and aberrant face perception in clinical populations. Composite paradigms continue to advance our knowledge of face perception, as exemplified by their recent use for investigating the perceptual mechanisms underlying dynamic face processing. However, the paradigm has been the subject of intense scrutiny, particularly over the last decade, and there is a growing sense that the composite face illusion, whilst easy to illustrate, is deceptively difficult to measure and interpret. In this review, we provide a focussed overview of the existing composite face literature, and identify six priorities for future research. Addressing these gaps in our knowledge will aid the evaluation and refinement of theoretical accounts of the illusion.     

Holistic face processing is mature at 4 years of age: evidence from the composite face effect

Although it is acknowledged that adults integrate features into a representation of the whole face, there is still some disagreement about the onset and developmental course of holistic face processing. We tested adults and children from 4 to 6 years of age with the same paradigm measuring holistic face processing through an adaptation of the composite face effect [Young, A. W., Hellawell, D., & Hay, D. C. (1987). Configurational information in face perception. Perception, 16, 747-759]. In Experiment 1, only 6-year-old children and adults tended to perceive the two identical top parts as different, suggesting that holistic face processing emerged at 6 years of age. However, Experiment 2 suggested that these results could be due to a response bias in children that was cancelled out by always presenting two faces in the same format on each trial. In this condition, all age groups present strong composite face effects, suggesting that holistic face processing is mature as early as after 4 years of experience with faces.     

Face perception: A very special issue

The perception of a face allows us to recognize the person, infer his or her emotional state, better understand what the person is saying, and derive general information, such as age and gender. This unique visual stimulus has generated a wealth of research, and subsequently theoretical and methodological debate. This special issue brings together 16 original papers that show the extraordinary diversity and fruitfulness of the approaches now being pursued. They are aimed at understanding different aspects of face perception in populations ranging from healthy children to adults with brain lesions and with techniques covering the entire spectrum from paper‐and‐pencil tests to functional brain imaging. Together, these contributions provide an insightful overview of the current state of research on face perception and exemplify the questions that dominate the field. To one such question, whether ‘face perception’ is a special issue in the broad field of the cognitive neurosciences, the answer is clearly yes!     

Fitting the child's mind to the world: adaptive norm-based coding of facial identity in 8-year-olds

In adults, facial identity is coded by opponent processes relative to an average face or norm, as evidenced by the face identity aftereffect: adapting to a face biases perception towards the opposite identity, so that a previously neutral face (e.g. the average) resembles the identity of the computationally opposite face. We investigated whether children as young as 8 use adaptive norm-based coding to represent faces, a question of interest because 8-year-olds are less accurate than adults at recognizing faces and do not show the adult neural markers of face expertise. We found comparable face identity aftereffects in 8-year-olds and adults: perception of identity in both groups shifted in the direction predicted by norm-based coding. This finding suggests that, by 8 years of age, the adaptive computational mechanisms used to code facial identity are like those of adults and hence that children's immaturities in face processing arise from another source.     

Super-recognizers: People with extraordinary face recognition ability

We tested 4 people who claimed to have significantly better than ordinary face recognition ability. Exceptional ability was confirmed in each case. On two very different tests of face recognition, all 4 experimental subjects performed beyond the range of control subject performance. They also scored significantly better than average on a perceptual discrimination test with faces. This effect was larger with upright than with inverted faces, and the 4 subjects showed a larger “inversion effect” than did control subjects, who in turn showed a larger inversion effect than did developmental prosopagnosics. This result indicates an association between face recognition ability and the magnitude of the inversion effect. Overall, these “super-recognizers” are about as good at face recognition and perception as developmental prosopagnosics are bad. Our findings demonstrate the existence of people with exceptionally good face recognition ability and show that the range of face recognition and face perception ability is wider than has been previously acknowledged.     

The own-species face bias: A review of developmental and comparative data

Face recognition is characterized in part by biases resulting in enhanced perception and memory for individuals within frequently encountered groups and impaired recognition for individuals within uncommonly encountered groups. These biases are found across multiple categories and levels, including species, race, age, and gender (Scherf & Scott, 2012). At the highest level of categorization, human adults and nonhuman primates exhibit improved recognition (Dufour, Pascalis, & Petit, 2006; Pascalis & Bachevalier, 1998) and discrimination abilities (Pascalis, de Haan, & Nelson, 2002) for individuals within their own species, reflecting what has been called an “own-species” or “species-specific” bias in face processing. The own-species bias is a model system for delineating the role of experience and the developmental trajectory of face-processing biases, for further understanding the malleability of face biases in adults, and for examining and comparing face-processing abilities across species. Here, we will review findings from studies investigating the perception of other-species faces during development, into adulthood and across species.     

Developmental changes in face recognition during childhood: Evidence from upright and inverted faces

Adults are experts at recognizing faces but there is controversy about how this ability develops with age. We assessed 6- to 12-year-olds and adults using a digitized version of the Benton Face Recognition Test, a sensitive tool for assessing face perception abilities. Children's response times for correct responses did not decrease between ages 6 and 12, for either upright or inverted faces, but were significantly longer than those of adults for both face types. Accuracy improved between ages 6 and 12, significantly more for upright than inverted faces. Inverted face recognition improved slowly until late childhood, whereas there was a large improvement in upright face recognition between ages 6 and 8, with a further enhancement after age 12. These results provide further evidence that during childhood face processing undergoes protracted development and becomes increasingly tuned to upright faces.     

Speech perception and short-term memory deficits in persistent developmental speech disorder

Children with developmental speech disorders may have additional deficits in speech perception and/or short-term memory. To determine whether these are only transient developmental delays that can accompany the disorder in childhood or persist as part of the speech disorder, adults with a persistent familial speech disorder were tested on speech perception and short-term memory. Nine adults with a persistent familial developmental speech disorder without language impairment were compared with 20 controls on tasks requiring the discrimination of fine acoustic cues for word identification and on measures of verbal and nonverbal short-term memory. Significant group differences were found in the slopes of the discrimination curves for first formant transitions for word identification with stop gaps of 40 and 20 ms with effect sizes of 1.60 and 1.56. Significant group differences also occurred on tests of nonverbal rhythm and tonal memory, and verbal short-term memory with effect sizes of 2.38, 1.56, and 1.73. No group differences occurred in the use of stop gap durations for word identification. Because frequency-based speech perception and short-term verbal and nonverbal memory deficits both persisted into adulthood in the speech-impaired adults, these deficits may be involved in the persistence of speech disorders without language impairment.     

The development of memory for own- and other-race faces

This study demonstrates that experience and development interact to influence the "cross-race effect." In a multination study (n=245), Caucasian children and adults of European ancestry living in the United States, Norway, or South Africa, as well as biracial (Caucasian-African American) children and adults living in the United States, were tested for recognition of Asian, African, and Caucasian faces. Regardless of national or biracial background, 8- to 10-year-olds, 12- to 14-year-olds, and adults recognized own-race faces more accurately than other-race faces, and did so to a similar extent, whereas 5- to 7-year-olds recognized all face types equally well. This same developmental pattern emerged for biracial children and adults. Thus, early meaningful exposure did not substantially alter the developmental trajectory. During young childhood, developmental influences on face processing operate on a system sufficiently plastic to preclude, under certain conditions, the cross-race effect.     

Age-related differences in face processing: a meta-analysis of three functional neuroimaging experiments.

Differences between young and old adults in brain activity, measured with positron emission tomography, were examined during three face processing experiments: episodic memory, working memory, and degraded face perception. Each experiment contained an easy face matching condition and a more difficult processing condition. Young adults showed greater activity in bilateral prefrontal cortex during the memory tasks, compared to face matching, but no difference in prefrontal activity between degraded and nondegraded perception. Older adults, on the other hand, had greater prefrontal activity in both memory and degraded perceptual tasks compared to matching. This suggests that increased prefrontal activity is task-specific in young adults, but, in old adults, is a more general response to increased cognitive effort or need for resources. These data are consistent with the dedifferentiation hypothesis of aging, and suggest a possible neural mechanism for this dedifferentiation, such that dependence on prefrontal activity across a greater number of tasks could also increase the amount of covariance across these tasks.     

Atypically heterogeneous vertical first fixations to faces in a case series of people with developmental prosopagnosia

ABSTRACT

When people recognize faces, they normally move their eyes so that their first fixation is in the optimal location for efficient perceptual processing. This location is found just below the centre-point between the eyes. This type of attentional bias could be partly innate, but also an inevitable developmental process that aids our ability to recognize faces. We investigated whether a group of people with developmental prosopagnosia would also demonstrate neurotypical first fixation locations when recognizing faces during an eye-tracking task. We found evidence that adults with prosopagnosia had atypically heterogeneous first fixations in comparison to controls. However, differences were limited to the vertical, but not horizontal, plane of the face. We interpret these findings by suggesting that subtle changes to face-based eye movement patterns in developmental prosopagnosia may underpin their face recognition impairments, and suggest future work is still needed to address this possibility.     

The bonnie baby: experimentally manipulated temperament affects perceived cuteness and motivation to view infant faces

Attractive individuals are perceived as having various positive personality qualities. Positive personality qualities can in turn increase perceived attractiveness. However, the developmental origins of the link between attractiveness and personality are not understood. This is important because infant attractiveness (‘cuteness’) elicits caregiving from adults, and infant personality (‘temperament’) shapes caregiving behaviour. While research suggests that adults have more positive attitudes towards cuter infants, it is not known whether positive infant temperament can increase the perception of infant cuteness. We investigated the impact of experimentally established infant temperament on adults' perception of cuteness and desire to view individual faces. Ataseline, adults rated the cuteness of, and keypressed to view, images of unfamiliar infants with neutral facial expressions. Training required adults to learn about an infant's ‘temperament’, through repeated pairing of the neutral infant face with positive or negative facial expressions and vocalizations. Adults then re‐rated the original neutral infant faces. Post‐training, there were significant changes from baseline: infants who were mostly happy were perceived as cuter and adults expended greater effort to view them. Infants who were mostly sad were not perceived as cuter and adults expended less effort to view them. Our results suggest that temperament has clear consequences for how adults perceive ‘bonnie’ babies. Perception of infant cuteness is not based on physical facial features alone, and is modifiable through experience.     

Probing emotion in the developing brain: functional neuroimaging in the assessment of the neural substrates of emotion in normal and disordered children and adolescents

Virtually all developmental neuropsychiatric disorders involve some dysfunction or dysregulation of emotion. Moreover, many psychiatric disorders with adult onset have early subclinical manifestations in children. This essay selectively reviews the literature on the neuroimaging of affect and disorders of affect in children. Some critical definitional and conceptual issues are first addressed, including the distinctions between the perception and production of emotion and between emotional states and traits. Developmental changes in morphometric measures of brain structure are then discussed and the implications of such findings for studies of functional brain activity are considered. Data on functional neuroimaging and childhood depression are then reviewed. While the extant data in this area are meager, they are consistent with studies in adults that have observed decreased left-sided anterolateral prefrontal cortex activation in depression. Studies in children on the recognition of emotion and affective intent in faces using functional magnetic resonance imaging are then reviewed. These findings indicate that the amygdala plays an important role in such affective face processing in children, similar to the patterns of activation observed in adults. Moreover, one study has reported abnormalities in amygdala activation during a task requiring the judgment of affective intent from the eye region of the face in subjects with autism. Some of the methodological complexities of developmental research in this area are discussed, and directions for future research are suggested.