Early maturity of face recognition: No childhood development of holistic processing, novel face encoding, or face-space

Historically, it was believed the perceptual mechanisms involved in individuating faces developed only very slowly over the course of childhood, and that adult levels of expertise were not reached until well into adolescence. Over the last 10 years, there has been some erosion of this view by demonstrations that all adult-like behavioural properties are qualitatively present in young children and infants. Determining the age of maturity, however, requires quantitative comparison across age groups, a task made difficult by the need to disentangle development in face perception from development in all the other cognitive factors that affect task performance. Here, we argue that full quantitative maturity is reached early, by 5-7 years at the latest and possibly earlier. This is based on a comprehensive literature review of results in the 5-years-to-adult age range, with particular focus on the results of the few previous studies that are methodologically suitable for quantitative comparison of face effects across age, plus three new experiments testing development of holistic/configural processing (faces versus objects, disproportionate inversion effect), ability to encode novel faces (assessed via implicit memory) and face-space (own-age bias).     

Dissociating perceptual and representation-based contributions to priming of face recognition

Repetition priming of object identification refers to the phenomenon whereby experience with an object induces systematic changes in subsequent processing of that same object. This data-driven form of priming is distinct from conceptually-driven priming. To date, considerable controversy exists about whether data-driven priming reflects facilitation in perceptual processing or mediation by preexisting object representations. The present study concerned priming of recognizing familiar and unfamiliar faces and how this priming is influenced by face inversion, which interferes with perceptual face processing. Perceptual and representation-based loci conjointly contributed to priming; the perceptual locus was operative similarly for familiar and unfamiliar faces, whereas the representation-based locus was only invoked for familiar faces and resulted in a response-time reduction triple the magnitude of that from the perceptual locus. The results constrain theoretical accounts of data-driven priming by indicating that improved identification can result from the combination of perceptual and representation-based facilitation.     

Developing race categories in infancy via Bayesian face recognition

The other-race effect emerges during infancy following the perceptual narrowing of face recognition. Other-race faces that were previously discriminable in early infancy cannot be distinguished by older infants. I discuss a Bayesian model of this process that posits that the other-race effect may be a consequence of learning to distinguish between intrapersonal variation (changes to face appearance that preserve identity) and extrapersonal variation (changes that do not preserve identity) in a visual environment in which a subset of race categories dominate. I demonstrate that race categories, which I have previously argued are a critical precursor to the emergence of the other-race effect in infancy, are a natural by-product of this model. Perceptual narrowing for race may thus be a natural consequence of visual experience and the estimation of face variability based on a growing number of exemplars. I describe the basic architecture of the model, its applicability to a range of visual learning scenarios, and identify critical choices one faces in applying the model to a specific perceptual task. Despite the success of the model in accounting for these behavioural results, I conclude by identifying important shortcomings of the model and describe important challenges for future efforts to characterize the development of the other-race effect computationally.     

Multiple perceptual strategies used by macaque monkeys for face recognition

Successful integration of individuals in macaque societies suggests that monkeys use fast and efficient perceptual mechanisms to discriminate between conspecifics. Humans and great apes use primarily holistic and configural, but also feature-based, processing for face recognition. The relative contribution of these processes to face recognition in monkeys is not known. We measured face recognition in three monkeys performing a visual paired comparison task. Monkey and humans faces were (1) axially rotated, (2) inverted, (3) high-pass filtered, and (4) low-pass filtered to isolate different face processing strategies. The amount of time spent looking at the eyes, mouth, and other facial features was compared across monkey and human faces for each type of stimulus manipulation. For all monkeys, face recognition, expressed as novelty preference, was intact for monkey faces that were axially rotated or spatially filtered and was supported in general by preferential looking at the eyes, but was impaired for inverted faces in two of the three monkeys. Axially rotated, upright human faces with a full range of spatial frequencies were also recognized, however, the distribution of time spent exploring each facial feature was significantly different compared to monkey faces. No novelty preference, and hence no inferred recognition, was observed for inverted or low-pass filtered human faces. High-pass filtered human faces were recognized, however, the looking pattern on facial features deviated from the pattern observed for monkey faces. Taken together these results indicate large differences in recognition success and in perceptual strategies used by monkeys to recognize humans versus conspecifics. Monkeys use both second-order configural and feature-based processing to recognize the faces of conspecifics, but they use primarily feature-based strategies to recognize human faces.     

Eye-tracking the own-race bias in face recognition: Revealing the perceptual and socio-cognitive mechanisms

Own-race faces are recognised more accurately than other-race faces and may even be viewed differently as measured by an eye-tracker (Goldinger, Papesh, & He, 2009). Alternatively, observer race might direct eye-movements (Blais, Jack, Scheepers, Fiset, & Caldara, 2008). Observer differences in eye-movements are likely to be based on experience of the physiognomic characteristics that are differentially discriminating for Black and White faces. Two experiments are reported that employed standard old/new recognition paradigms in which Black and White observers viewed Black and White faces with their eye-movements recorded. Experiment 1 showed that there were observer race differences in terms of the features scanned but observers employed the same strategy across different types of faces. Experiment 2 demonstrated that other-race faces could be recognised more accurately if participants had their first fixation directed to more diagnostic features using fixation crosses. These results are entirely consistent with those presented by Blais et al. (2008) and with the perceptual interpretation that the own-race bias is due to inappropriate attention allocated to the facial features ( and ).     

熟悉面孔与陌生面孔识别的差异

摘 要：面孔识别包括熟悉面孔识别和陌生面孔识别,两者之间的差异已经得到了多方面的证明。神经生理学的研究发现,识别陌生面孔和熟悉面孔所激活的脑区存在差异,与识别陌生面孔相比,识别熟悉面孔的脑区活动范围更大,包括双侧前额叶、单侧颞叶、海马回、杏仁核、后扣带回和右下额叶。并且也存在脑电的差异,比如 N400和P600的差异。对陌生面孔和熟悉面孔识别具有相同影响的因素有：遮挡、倒置等;具有不同影响的因素有：视角、表情、内外部特征等。文章也探讨了陌生面孔变成熟悉面孔的过程,以及在这一过程中起主要作用的编码形式等。     

Bayesian confusions surrounding simplicity and likelihood in perceptual organization

In the study of perceptual organization, the Occamian simplicity principle (which promotes efficiency) and the Helmholtzian likelihood principle (which promotes veridicality) have been claimed to be equivalent. Proposed models of these principles may well yield similar outcomes (especially in everyday situations), but as argued here, claims that the principles are equivalent confused subjective probabilities (which are used in Bayesian models of the Occamian simplicity principle) and objective probabilities (which are needed in Bayesian models of the Helmholtzian likelihood principle). Furthermore, Occamian counterparts of Bayesian priors and conditionals have led to another confusion, which seems to have been triggered by a dual role of regularity in perception. This confusion is discussed by contrasting complete and incomplete Occamian approaches to perceptual organization.     

Caricature and face recognition

Although caricatures are often gross distortions of faces, they frequently appear to be super-portraits capable of eliciting recognition better than veridical depictions. This may occur because faces are encoded as distinctive feature deviations from a prototype. The exaggeration of these deviations in a caricature may enhance recognition because it emphasizes the features of the face that are encoded. In two experiments, we tested the superportrait hypothesis and the encoding-by-caricature hypothesis. In the first experiment, caricatures were recognized better than faces, and true caricatures of previously seen faces were recognized better than the faces from which the caricatures had been developed. In the second experiment, faces and their caricatures were tachistoscopically presented in a sequential same/different reaction time task. Subjects were slower to distinguish the stimuli when the face preceded its caricature, indicating that caricatures are more similar to the encoded representation of a face than are stimuli in which the distinctive features are deemphasized.     

Disrupting perceptual grouping of face parts impairs holistic face processing

Face perception is widely believed to involve integration of facial features into a holistic perceptual unit, but the mechanisms underlying this integration are relatively unknown. We examined whether perceptual grouping cues influence a classic marker of holistic face perception, the “composite-face effect.” Participants made same–different judgments about a cued part of sequentially presented chimeric faces, and holistic processing was indexed as the degree to which the task-irrelevant face halves impacted performance. Grouping was encouraged or discouraged by adjusting the backgrounds behind the face halves: Although the face halves were always aligned, their respective backgrounds could be misaligned and of different colors. Holistic processing of face, but not of nonface, stimuli was significantly reduced when the backgrounds were misaligned and of different colors, cues that discouraged grouping of the face halves into a cohesive unit (Exp. 1). This effect was sensitive to stimulus orientation at short (200 ms) but not at long (2,500 ms) encoding durations, consistent with the previously documented temporal properties of the holistic processing of upright and inverted faces (Exps. 2 and 3). These results suggest that grouping mechanisms, typically involved in the perception of objecthood more generally, might contribute in important ways to the holistic perception of faces.     

Race-based perceptual asymmetries underlying face processing in infancy

Adults process other-race faces differently than own-race faces. For instance, a single other-race face in an array of own-race faces attracts Caucasians’ attention, but a single own-race face among other-race faces does not. This perceptual asymmetry has been explained by the presence of an other-race feature in other-race faces and its absence in own-race faces; this difference is thought to underlie race-based differences in face processing. We examined the developmental origins of this mechanism in two groups of Caucasian 9-month-olds. Infants in the experimental group exhibited a preference for a pattern containing a single Asian face among seven Caucasian faces over a pattern containing a single Caucasian face among seven Asian faces. This preference was not driven by the majority of elements in the images, because a control group of infants failed to exhibit a preference between homogeneous patterns containing eight Caucasian versus eight Asian faces. The results demonstrate that an other-race face among own-race faces attracts infants’ attention but not vice versa. This perceptual asymmetry suggests that the other-race feature is available to Caucasians by 9 months of age, thereby indicating that mechanisms of specialization in face processing originate early in life.     

Parts and wholes in face recognition

Are faces recognized using more holistic representations than other types of stimuli? Taking holistic representation to mean representation without an internal part structure, we interpret the available evidence on this issue and then design new empirical tests. Based on previous research, we reasoned that if a portion of an object corresponds to an explicitly represented part in a hierarchical visual representation, then when that portion is presented in isolation it will be identified relatively more easily than if it did not have the status of an explicitly represented part. The hypothesis that face recognition is holistic therefore predicts that a part of a face will be disproportionately more easily recognized in the whole face than as an isolated part, relative to recognition of the parts and wholes of other kinds of stimuli. This prediction was borne out in three experiments: subjects were more accurate at identifying the parts of faces, presented in the whole object, than they were at identifying the same part presented in isolation, even though both parts and wholes were tested in a forced-choice format and the whole faces differed only by one part. In contrast, three other types of stimuli--scrambled faces, inverted faces, and houses--did not show this advantage for part identification in whole object recognition.     

Satiation in name and face recognition

Massive repetition of a word can lead to a loss of meaning (i.e., semantic satiation). Satiation is a general property of neurons and so it would be expected that semantic satiation would be found for stimuli other than words. Three experiments examined the occurrence of satiation for the repetition of names, the visualization of faces, and the repetition of faces. Reaction times to a decision based on a repeated name or face were longer following 30 repetitions than following 3 repetitions, indicating that satiation had occurred. Mere visualization over the same time interval, however, did not elicit satiation effects.     

Peripheral target recognition and visual field narrowing in aviators and nonaviators

In the two experiments that examined recognition accuracy in the near visual periphery as a function of foveal cognitive load, aviators were shown to have larger effective functional visual fields than nonaviators. The aviators appeared to be far less susceptible to the visual field narrowing found in nonaviators. The narrowing found in nonaviators suggested a tunnel-vision-like pattern. The rather small effect of load increases on aviator performance was likely due to specialized training and experience. Student aviators who averaged only 70 flight hr were clearly superior to nonaviators on peripheral recognition with a concomitant foveal task.     

Development of perceptual expertise in emotion recognition

How do children’s early social experiences influence their perception of emotion-specific information communicated by the face? To examine this question, we tested a group of abused children who had been exposed to extremely high levels of parental anger expression and physical threat. Children were presented with arrays of stimuli that depicted the unfolding of facial expressions, from neutrality to peak emotions. The abused children accurately recognized anger early in the formation of the facial expression, when few physiological cues were available. The speed of children’s recognition was associated with the degree of anger/hostility reported by the child’s parent. These data highlight the ways in which perceptual learning can shape the timing of emotion perception.     

The other-race effect develops during infancy: evidence of perceptual narrowing

Experience plays a crucial role in the development of face processing. In the study reported here, we investigated how faces observed within the visual environment affect the development of the face-processing system during the 1st year of life. We assessed 3-, 6-, and 9-month-old Caucasian infants' ability to discriminate faces within their own racial group and within three other-race groups (African, Middle Eastern, and Chinese). The 3-month-old infants demonstrated recognition in all conditions, the 6-month-old infants were able to recognize Caucasian and Chinese faces only, and the 9-month-old infants' recognition was restricted to own-race faces. The pattern of preferences indicates that the other-race effect is emerging by 6 months of age and is present at 9 months of age. The findings suggest that facial input from the infant's visual environment is crucial for shaping the face-processing system early in infancy, resulting in differential recognition accuracy for faces of different races in adulthood.     

Units of episodic memory in perceptual recognition

Two studies examined the cognitive units of sentence memory using a perceptual recognition task. Four candidate cognitive units were considered: concepts, propositions, integrated propositions, and nonintegrated propositions. Subjects first received a list of acquisition sentences and then were asked to reproduce sentences presented under a white-noise mask. These masked sentences were replicas of the acquisition sentences, were formed of recombined clauses from the acquisition sentences, or were formed of recombined words from the acquisition sentences. Reproduction accuracy was employed as the dependent measure. Results supported propositions (operationalized by clauses) as cognitive units of episodic memory. No conclusive evidence was obtained for concepts, integrated propositions, or nonintegrated propositions as cognitive units. The utility of perceptual recognition tasks for studying the cognitive units of episodic memory is discussed.     

Similarity effects in face recognition

Three experiments are described which examine the effects of similarity on face recognition using a new application of hierarchical clustering analysis (HCS). Experiments I and II employed a within-groups design where subjects attempted to recognize targets among decoys from the same and different cluster to the target. Common cluster membership accounted for 72% and 84%, respectively, of all false alarms in the two experiments. Absolute error rates were affected by the number of targets actually present in the array and the style of the instructions given to subjects but were not influenced by whether successive or simultaneous test presentation was employed. Experiment III used a between-subject design where targets were embedded in arrays composed from same or different clusters. False alarm rates were significantly higher for the same cluster condition, but hit rates were unaffected by recognition context. The significance of these findings for theories of face identification is discussed.