An inner face advantage in children's recognition of familiar peers

Children’s recognition of familiar own-age peers was investigated. Chinese children (4-, 8-, and 14-year-olds) were asked to identify their classmates from photographs showing the entire face, the internal facial features only, the external facial features only, or the eyes, nose, or mouth only. Participants from all age groups were familiar with the faces used as stimuli for 1 academic year. The results showed that children from all age groups demonstrated an advantage for recognition of the internal facial features relative to their recognition of the external facial features. Thus, previous observations of a shift in reliance from external to internal facial features can be attributed to experience with faces rather than to age-related changes in face processing.     

Perceptual learning and acquired face familiarity: Evidence from inversion,use of internal features,and generalization between viewpoints

Pairs of similar faces were created from photographs of different people using morphing software. The ability of participants to discriminate between novel pairs of faces and between those to which they had received brief, unsupervised, exposure (5×2 s each) was assessed. In all experiments exposure improved discrimination performance. Overall, discrimination was better when the faces were upright, but exposure produced improved discrimination for both upright and inverted faces (Experiment 1). The improvement produced by exposure was selective to internal face features (Experiment 2) and was evident when there was a change in orientation (three-quarter to full face or vice versa) between exposure and test (Experiment 3). These findings indicate that perceptual learning observed following brief exposure to faces exhibit well-established hallmarks of familiar face processing (i.e., internal feature advantage and insensitivity to a change of viewpoint). Considered in combination with previous studies using the same type of stimuli (Mundy, Honey, & Dwyer, 2007), the current results imply that general perceptual learning mechanisms contribute to the acquisition of face familiarity.     

Identification of familiar and unfamiliar faces from internal and external features: some implications for theories of face recognition

Three experiments are reported in which recognition of faces from whole faces or internal or external features was compared. In the first experiment, where the faces were of famous people, an advantage was found for identification from internal features. In the second experiment involving unfamiliar faces, however, no difference was found in recognition rates when subjects were given the internal or the external features. In a third experiment famous faces were presented and mixed with other famous faces for a recognition test. As in experiment 1, better recognition occurred from internals as compared with external features. It is argued that the internal representation for familiar faces may be qualitatively different from that for face seen just once. In particular some advantage in feature saliency may accrue to the internal or 'expressive' features of familiar faces. The implications of these results are considered in relation to general theories of face perception and recognition.     

“Do I Know You?” Altering hairstyle affects facial recognition

Background: Research has demonstrated that both internal features (e.g., eyes) and external features (e.g., hair) are important for recognizing unfamiliar faces; however, the impact of altering hairstyle on the recognition of unfamiliar faces has yet to be isolated and investigated in the absence of deep processing. Objectives: We sought to examine the extent to which altering hair impacts the recognition of a previously viewed face. Methods: Participants were presented with a series of face images followed by a recognition probe of either a new face or a face that was among the previously presented images with either the same hairstyle (identical face) or a different hairstyle (disguised face). Results: Participants showed significantly less accuracy in the disguised condition compared to the identical condition. Conclusions: Our results provide evidence that hairstyle plays a role in recognizing unfamiliar faces. This appears to hold true across race and sex, as well as across deep and shallow processing.     

Getting to know you: How we learn new faces

Previous work has shown an advantage for matching the internal features of familiar faces in contrast to an advantage for the external features of unfamiliar faces. In the current experiment, we tracked this shift towards an internal feature advantage as subjects were familiarized with a set of initially unfamiliar faces. They were asked to learn a set of 24 faces from video images and complete a face matching task on 3 consecutive days. Half of the faces were learned from moving images while the others were learned from static images to determine whether movement was necessary to produce the internal advantage found when matching familiar faces. We found that by the end of the 3 days, performance on the internal features had improved and was equivalent to performance on the external features. In contrast, matching of the external features remained at a relatively constant level across the experiment. Faces were learned equally well from moving and static images suggesting that movement is not necessary to promote learning of the internal features.     

Robust representations of individual faces in chimpanzees (<Emphasis Type="Italic">Pan troglodytes</Emphasis>) but not monkeys (<Emphasis Type="Italic">Macaca mulatta</Emphasis>)

Being able to recognize the faces of our friends and family members no matter where we see them represents a substantial challenge for the visual system because the retinal image of a face can be degraded by both changes in the person (age, expression, pose, hairstyle, etc.) and changes in the viewing conditions (direction and degree of illumination). Yet most of us are able to recognize familiar people effortlessly. A popular theory for how face recognition is achieved has argued that the brain stabilizes facial appearance by building average representations that enhance diagnostic features that reliably vary between people while diluting features that vary between instances of the same person. This explains why people find it easier to recognize average images of people, created by averaging multiple images of the same person together, than single instances (i.e. photographs). Although this theory is gathering momentum in the psychological and computer sciences, there is no evidence of whether this mechanism represents a unique specialization for individual recognition in humans. Here we tested two species, chimpanzees (Pan troglodytes) and rhesus monkeys (Macaca mulatta), to determine whether average images of different familiar individuals were easier to discriminate than photographs of familiar individuals. Using a two-alternative forced-choice, match-to-sample procedure, we report a behaviour response profile that suggests chimpanzees encode the faces of conspecifics differently than rhesus monkeys and in a manner similar to humans.     

Matching familiar and unfamiliar faces on internal and external features

Two experiments are reported in which subjects were asked to match a photograph of a complete face and a simultaneously presented photograph of internal or external features of a face, deciding whether or not the two photographs were pictures of the same person. In experiment 1 'same' pairs were derived from different pictures of the same face, so that subjects had to match the faces and not the particular photographs used. Matches based on internal features were found to be faster for familiar than for unfamiliar faces, whereas there was no difference in reaction time between matches based on the external features of familiar and unfamiliar faces. Faster matching of internal features of familiar faces was found to hold equally for pairs of photographs that differed in orientation of the face or in facial expression. In experiment 2 'same' pairs were derived from the same photographs, which gave subjects the choice of matching on the basis of the features of the depicted faces or matching the photographs. Reaction times were faster than in experiment 1, and there were no differences between familiar and unfamiliar faces. The study confirms reports of differential saliency of the internal features of familiar faces, and shows that this only holds when stimuli are treated as faces. The finding thus reflects properties of structural rather than pictorial codes.     

Exploring levels of face familiarity by using an indirect face-matching measure

An experiment is reported in which participants matched complete images of unfamiliar, moderately familiar, and highly familiar faces with simultaneously presented images of internal and external features. Participants had to decide if the two images depicted same or different individuals. Matches to internal features were made faster to highly familiar faces than both to moderately familiar and to unfamiliar faces, and matches to moderately familiar faces were made faster than to unfamiliar faces. For external feature matches, this advantage was only found for "different" decision matches to highly familiar faces compared to unfamiliar faces. The results indicate that the differences in familiar and unfamiliar face processing are not the result of all-or-none effects, but seem to have a graded impact on matching performance. These findings extend the earlier work of Young et al (1985 Perception 14 737-746), and we discuss the possibility of using the matching task as an indirect measure of face familiarity.     

7-11-year-old children show an advantage for matching and recognizing the internal features of familiar faces: Evidence against a developmental shift

Adults are better at recognizing familiar faces from the internal facial features (eyes, nose, mouth) than from the external facial features (hair, face outline). However, previous research suggests that this “internal advantage” does not appear until relatively late in childhood, and some studies suggest that children rely on external features to recognize all faces, whether familiar or not. We use a matching task to examine face processing in 7-8- and 10-11-year-old children. We use a design in which all face stimuli can be used as familiar items (for participants who are classmates) and unfamiliar items (for participants from a different school). Using this design, we find an internal feature advantage for matching familiar faces, for both groups of children. The same children were then shown the external and internal features of their classmates and were asked to name or otherwise identify them. Again, both age groups identified more of their classmates correctly from the internal than the external features. This is the first time an internal advantage has been reported in this age group. Results suggest that children as young as 7 process faces in the same way as do adults, and that once procedural difficulties are overcome, the standard effects of familiarity are observed.     

The relative importance of external and internal features of facial composites

Three experiments are reported that compare the quality of external with internal regions within a set of facial composites using two matching‐type tasks. Composites are constructed with the aim of triggering recognition from people familiar with the targets, and past research suggests internal face features dominate representations of familiar faces in memory. However the experiments reported here show that the internal regions of composites are very poorly matched against the faces they purport to represent, while external feature regions alone were matched almost as well as complete composites. In Experiments 1 and 2 the composites used were constructed by participant‐witnesses who were unfamiliar with the targets and therefore were predicted to demonstrate a bias towards the external parts of a face. In Experiment 3 we compared witnesses who were familiar or unfamiliar with the target items, but for both groups the external features were much better reproduced in the composites, suggesting it is the process of composite construction itself which is responsible for the poverty of the internal features. Practical implications of these results are discussed.     

Orangutans (Pongo abelii) and a gorilla (Gorilla gorilla gorilla) match features in familiar and unfamiliar individuals

Great apes can perceive images as representative of corresponding real-life objects. Coupled with the potential advantages of identifying specific members of one’s species and mounting evidence for individual recognition in other non-humans, it seems likely that great apes would have the ability to identify conspecifics in photographs. The ability of four orangutans and a gorilla to match images of individuals of their own and a closely related but unfamiliar species was examined here for the first time. First, the subjects matched photographs of familiar conspecifics taken at various time points in a delayed matching-to-sample procedure (Experiment 1). Second, they matched different photographs of unfamiliar individuals of a different species (Experiment 2) at above chance levels. These results suggest that the subjects matched photographs by matching physical features, not necessarily by recognizing the identity of the individuals depicted. However, they also quickly learned to select photographs of familiar individuals when these photographs were paired with photographs of unfamiliar individuals of their own species (Experiment 3), and three subjects showed transfer to novel images of familiar and unfamiliar individuals. Thus, the findings support the idea that subjects attended to physical features to identify individuals that they could categorize on the basis of familiarity.     

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。     

The inversion effect in infancy: the role of internal and external features

The present work examined the changing role of inner and outer facial features in the recognition of upright and inverted faces in 5-, 7-, and 9-month-olds. Study 1 established that the “inversion effect” (impaired recognition of an inverted face) was present in infants as young as 5 months. In Study 2, internal and external features were inverted separately. Disrupting the internal configuration by inversion impaired recognition at all ages; disrupting the external configuration impaired recognition only at 5-months. In Study 3, an upright familiar face was paired with one having either novel internal or novel external features. The results confirmed that the 5-month-olds used only the external features to recognize faces, whereas older infants were as adept at using internal features as external ones. These findings suggest a shift, after 5 months, away from dependence on external features for face recognition and toward greater reliance on internal ones.     

Does matching of internal and external facial features depend on orientation and viewpoint?

Although it is recognized that external (hair, head and face outline, ears) and internal (eyes, eyebrows, nose, mouth) features contribute differently to face recognition it is unclear whether both feature classes predominately stimulate different sensory pathways. We employed a sequential speed-matching task to study face perception with internal and external features in the context of intact faces, and at two levels of contextual congruency. Both internal and external features were matched faster and more accurately in the context of totally congruent/incongruent facial stimuli compared to just featurally congruent/incongruent faces. Matching of totally congruent/incongruent faces was not affected by the matching criteria, but was strongly modulated by orientation and viewpoint. On the contrary, matching of just featurally congruent/incongruent faces was found to depend on the feature class to be attended, with strong effects of orientation and viewpoint only for matching of internal features, but not of external features. The data support the notion that different processing mechanisms are involved for both feature types, with internal features being handled by configuration sensitive mechanisms whereas featural processing modes dominate when external features are the focus.     

Constraints on view combination: effects of self-occlusion and differences among familiar and novel views

The use of multiple familiar views of objects to facilitate recognition of novel views has been addressed in a number of behavioral studies, but the results have not been conclusive. The present study was a comprehensive examination of view combination for different types of novel views (internal or external to the studied views) and different objects (amoeboid objects and objects composed of geons; objects with and without self-occlusion across rotation). The authors found that the advantage gained from the study of 2 views was more than the generalization from each of the studied views presented alone. This facilitation occurred only for internal views but not external views. In addition, the benefits from the study of 2 views diminished when (a) the studied views did not share the same visible features and when (b) the studied views were separated by a small angular difference.     

The Headscarf Effect: Direct Evidence from the Eyewitness Identification Paradigm

Internal and external features dominate familiar and unfamiliar face recognition, respectively. However, this finding is not universal; Egyptians showed a robust internal‐feature advantage for processing unfamiliar faces (Megreya & Bindemann, 2009). This bias was speculatively attributed to their long‐term experiences for individuating female faces with headscarves, which completely cover the external features. Here, we provided an empirical test for this suggestion. Participants from Egypt and UK were presented with a staged crime, which was committed by an own‐race woman with or without a headscarf. All participants were then asked to identify the culprit from a line‐up involving 10 faces with or without headscarves. British participants showed an advantage when the culprit left her hair uncovered. In contrast, Egyptian observers showed an advantage when the culprit wore a headscarf. This Egyptian headscarf effect was also replicated using British faces, suggesting that it reflects a specific characteristic of participant nationality rather than face nationality. These results therefore provide evidence for how culture influences cognition. Copyright © 2011 John Wiley & Sons, Ltd.     

Three-Dimensional Information in Face Representations Revealed by Identity Aftereffects

ABSTRACT— Representations of individual faces evolve with experience to support progressively more robust recognition. Knowledge of three-dimensional face structure is required to predict an image of a face as illumination and viewpoint change. Robust recognition across such transformations can be achieved with representations based on multiple two-dimensional views, three-dimensional structure, or both. We used face-identity adaptation in a familiarization paradigm to address a long-standing controversy concerning the role of two-dimensional versus three-dimensional information in face representations. We reasoned that if three-dimensional information is coded in the representations of familiar faces, then learning a new face using images generated by one three-dimensional transformation should enhance the robustness of the representation to another type of three-dimensional transformation. Familiarization with multiple views of faces enhanced the transfer of face-identity adaptation effects across changes in illumination by compensating for a generalization cost at a novel test viewpoint. This finding demonstrates a role for three-dimensional information in representations of familiar faces.     

Repetition priming from moving faces

Recent experiments have suggested that seeing a familiar face move provides additional dynamic information to the viewer, useful in the recognition of identity. In four experiments, repetition priming was used to investigate whether dynamic information is intrinsic to the underlying face representations. The results suggest that a moving image primes more effectively than a static image, even when the same static image is shown in the prime and the test phases (Experiment 1). Furthermore, when moving images are presented in the test phase (Experiment 2), there is an advantage for moving prime images. The most priming advantage is found with naturally moving faces, rather than with those shown in slow motion (Experiment 3). Finally, showing the same moving sequence at prime and test produced more priming than that found when different moving sequences were shown (Experiment 4). The results suggest that dynamic information is intrinsic to the face representations and that there is an advantage to viewing the same moving sequence at prime and test.     

Variability in photos of the same face

Psychological studies of face recognition have typically ignored within-person variation in appearance, instead emphasising differences between individuals. Studies typically assume that a photograph adequately captures a person’s appearance, and for that reason most studies use just one, or a small number of photos per person. Here we show that photographs are not consistent indicators of facial appearance because they are blind to within-person variability. Crucially, this within-person variability is often very large compared to the differences between people. To investigate variability in photos of the same face, we collected images from the internet to sample a realistic range for each individual. In Experiments 1 and 2, unfamiliar viewers perceived images of the same person as being different individuals, while familiar viewers perfectly identified the same photos. In Experiment 3, multiple photographs of any individual formed a continuum of good to bad likeness, which was highly sensitive to familiarity. Finally, in Experiment 4, we found that within-person variability exceeded between-person variability in attractiveness. These observations are critical to our understanding of face processing, because they suggest that a key component of face processing has been ignored. As well as its theoretical significance, this scale of variability has important practical implications. For example, our findings suggest that face photographs are unsuitable as proof of identity.     

Sex differences in unfamiliar face identification: evidence from matching tasks

Research on sex differences in face recognition has reported mixed results, on balance suggesting an advantage for female observers. However, it is not clear whether this advantage is specific to face processing or reflects a more general superiority effect in episodic memory. The current study therefore examined sex differences with a face-matching task that eliminates memory demands. Across two experiments, female but not male observers showed an own-sex advantage on match trials, in which two pictures have to be identified as the same person. This advantage was present for whole faces and when only the internal or external facial features were shown. Female observers were also more accurate in these three conditions on mismatch encounters, in which two photographs have to be identified as different people, but this reflects a more general effect that is present for male and female faces. These findings converge with claims of a female advantage in face recognition and demonstrate that this effect persists when memory demands are eliminated.