The ontogeny of face identity; I. Eight- to 21-week-old infants use internal and external face features in identity

A paradigm was designed to study how infants identify live faces. Eight- to 21-week-old infants were seated comfortably and were presented an adult female, dressed in a white laboratory coat and a white turtle neck sweater, until habituation ensued. The adult then left the room. One minute later either she or an identically garbed confederate returned. Looking time did not increase above habituation levels when the original experimenter returned, but increased substantially when the confederate entered the room. Furthermore, internal features alone could serve as the basis of face identity. Looking times of infants who had habituated to experimenters with masked outer features of hair, ears and neck also markedly increased when a second identically dressed experimenter returned. Identity in this instance could only be based on internal facial characteristics. A second study assessed the contributions of internal and external facial features to identity. Infants were habituated to an experimenter in a short wig. One minute later they saw her again, either in the same short wig or in a long one. Alternatively, they saw a second experimenter wearing either the short wig or the long one. Infants looked longer only to the stranger wearing the long wig. Very brief looking times occurred to the familiar adult, regardless of wig, and to the stranger wearing the familiar wig. This paradigm provides an approach to discover rules used by infants of different ages to process and identify adult faces and to establish the bases of face preference.     

Short-term memory effects on the representation of two-dimensional space in the rhesus monkey

Human subjects represent the location of a point in 2D space using two independent dimensions (x–y in Euclidean or radius-angle in polar space), and encode location in memory along these dimensions using two levels of representation: a fine-grain value and a category. Here we determined whether monkeys possessed the ability to represent location with these two levels of coding. A rhesus monkey was trained to reproduce the location of a dot in a circle by pointing, after a delay period, on the location where a dot was presented. Five different delay periods (0.5–5 s) were used. The results showed that the monkey used a polar coordinate system to represent the fine-grain spatial coding, where the radius and angle of the dots were encoded independently. The variability of the spatial response and reaction time increased with longer delays. Furthermore, the animal was able to form a categorical representation of space that was delay-dependent. The responses avoided the circumference and the center of the circle, defining a categorical radial prototype around one third of the total radial length. This radial category was observed only at delay durations of 3–5 s. Finally, the monkey also formed angular categories with prototypes at the obliques of the quadrants of the circle, avoiding the horizontal and vertical axes. However, these prototypes were only observed at the 5-s delay and on dots lying on the circumference. These results indicate that monkeys may possess spatial cognitive abilities similar to humans.     

Targets,tactics, and the open mouth face during play fighting in three species of primates

The play fighting of many mammals involves the nonserious use of behavior patterns derived from serious fighting. A major question of theoretical importance has been that of how, given this overlap in patterns of behavior, the animals can distinguish between playful and nonplayful intent. One proposed solution is that animals use play signals to inform each other about the playful intent of their actions. The most widely reported play signal amongst primates is the open mouth play face. The manner in which this so-called signal functions is based on correlational evidence, with most reports simply noting its presence or absence in a given species. This study involved a detailed video-based analysis of the occurrence of open mouths during the play fighting of three species of primates. One captive troop each of ring-tailed lemurs, black-handed spider monkeys, and patas monkeys was used. By examining all open mouths in the context of the species-typical style of play fighting, several conclusions were empirically verified. 1) Most open mouths occur as a functionally necessary precursor for biting. 2) Some open mouths occur as a defensive threat which deters further contact. 3) The residual open mouths which may function as contact promoting play signals, constituted about 20–25% of all open mouths by the lemurs and patas monkeys, but less than 5% for spider monkeys. These species differences appeared to arise from two causes. Firstly, the spider monkeys used another signal, the head shake, in situations where lemurs and patas monkeys used open mouths. Secondly, the style of play fighting greatly influenced the frequency and duration of open mouths. This was most marked in the face-to-face combat style of patas monkeys. These findings show that comparative studies of the occurrence and function of play signals need to take into account species-typical styles of playful combat. Aggr. Behav. 23:41–57, 1997. © 1997 Wiley-Liss, Inc.     

The effect of inversion on 3- to 5-year-olds’ recognition of face and nonface visual objects

This study compared the effect of stimulus inversion on 3- to 5-year-olds’ recognition of faces and two nonface object categories matched with faces for a number of attributes: shoes (Experiment 1) and frontal images of cars (Experiments 2 and 3). The inversion effect was present for faces but not shoes at 3 years of age (Experiment 1). Analogous results were found for boys when faces were compared with frontal images of cars. For girls, stimulus inversion impaired recognition of both faces and cars at 3 to 4 years of age, becoming specific to faces only at 5 years of age (Experiments 2 and 3). Evidence demonstrates that the ability to extract the critical cues that lead to adults’ efficient face recognition is selectively tuned to faces during preschool years.     

The approximation of a group stimulus space by averaging responses to selected subsets of the stimuli

This paper presents a simple random procedure for selecting subsets of stimulus pairs for presentation to subjects. The resulting set of ratings from the group of subjects allows the construction of a group (average) space through the use of the computer program TORSCA-9 or equivalent programs. The procedure is applied to both real and simulated data. It is found that subjects need only make between 20% and 50% of the usual judgements to reconstruct a reasonably accurate group space.     

The role of color in human face detection

Significant advances have been made in understanding human face recognition . However, a fundamental aspect of this process, how faces are located in our visual environment, is poorly understood and little studied. Here we examine the role of color in human face detection. We demonstrate that detection performance declines when color information is removed from faces, regardless of whether the surrounding scene context is rendered in color. Furthermore, faces rendered in unnatural colors are hard to detect, suggesting a role beyond simple segmentation. When faces are presented such that half the surface is colored appropriately, and half unnaturally, performance declines. This suggests that observers are not simply using the presence of skin color "patches" to detect faces. Rather, our data suggest that detection operates via a face template combining diagnostic color and face-shape information. These findings are consistent with color-template approaches used in some computer-based face detection systems.     

Aberrant pattern of scanning in prosopagnosia reflects impaired face processing

Visual scanpath recording was used to investigate the information processing strategies used by a prosopagnosic patient, SC, when viewing faces. Compared to controls, SC showed an aberrant pattern of scanning, directing attention away from the internal configuration of facial features (eyes, nose) towards peripheral regions (hair, forehead) of the face. The results suggest that SC's face recognition deficit can be linked to an inability to assemble an accurate and unified face percept due to an abnormal allocation of attention away from the internal face region. Extraction of stimulus attributes necessary for face identity recognition is compromised by an aberrant face scanning pattern.     

The role of higher level adaptive coding mechanisms in the development of face recognition

Developmental improvements in face identity recognition ability are widely documented, but the source of children’s immaturity in face recognition remains unclear. Differences in the way in which children and adults visually represent faces might underlie immaturities in face recognition. Recent evidence of a face identity aftereffect (FIAE), in which adaptation (exposure) to a particular identity causes a previously neutral face to take on the computationally opposite identity, suggests that adults code faces in an opponent fashion relative to an average face. One previous study showed comparable FIAEs in 8-year-olds and adults but did not demonstrate that adaptation was selective for high-level representations in both groups. Using a developmentally appropriate FIAE task, we investigated whether children show adult-like adaptation for facial identity when adapting and test images differ in size. Both age groups showed an equivalent FIAE, suggesting that qualitative changes in the use of higher level adaptive coding mechanisms do not drive the developmental improvements in face recognition ability, at least from 8 years of age.     

Female face preference in 4-month-olds: The importance of hairline

At 3–4 months of age, infants respond to gender information in human faces. Specifically, young infants display a visual preference toward female over male faces. In three experiments, using a visual preference task, we investigated the role of hairline information in this bias. In Experiment 1, we presented male and female composite faces with similar hairstyles to 4-month-olds and observed a preference for female faces. In Experiment 2, the faces were presented, but in this instance, without hairline cues, and the preference was eliminated. In Experiment 3, using the same cropping to eliminate hairline cues, but with feminized female faces and masculinized male faces, infants’ preference toward female faces was still not in evidence. The findings show that hairline information is important in young infants’ preferential orientation toward female faces.     

The complement of a point subset in a projective space and a Grassmann space

In a projective space we fix some set of points, a horizon, and investigate the complement of that horizon. We prove, under some assumptions on the size of lines, that the ambient projective space, together with its horizon, both can be recovered in that complement. Then we apply this result to show something similar for Grassmann spaces.     

The effect of face inversion on the detection of emotional faces in visual search

Past literature has indicated that face inversion either attenuates emotion detection advantages in visual search, implying that detection of emotional expressions requires holistic face processing, or has no effect, implying that expression detection is feature based. Across six experiments that utilised different task designs, ranging from simple (single poser, single set size) to complex (multiple posers, multiple set sizes), and stimuli drawn from different databases, significant emotion detection advantages were found for both upright and inverted faces. Consistent with past research, the nature of the expression detection advantage, anger superiority (Experiments 1, 2 and 6) or happiness superiority (Experiments 3, 4 and 5), differed across stimulus sets. However both patterns were evident for upright and inverted faces. These results indicate that face inversion does not interfere with visual search for emotional expressions, and suggest that expression detection in visual search may rely on feature-based mechanisms.     

The development of spatial frequency biases in face recognition

Previous research has suggested that a mid-band of spatial frequencies is critical to face recognition in adults, but few studies have explored the development of this bias in children. We present a paradigm adapted from the adult literature to test spatial frequency biases throughout development. Faces were presented on a screen with particular spatial frequencies blocked out by noise masks. A mid-band bias was found in adults and 9- and 10-year-olds for upright faces but not for inverted faces, suggesting a face-sensitive effect. However, 7- and 8-year-olds did not demonstrate the mid-band bias for upright faces but rather processed upright and inverted faces similarly. This suggests that specialization toward the mid-band for upright face recognition develops gradually during childhood and may relate to an advanced level of face expertise.     

The role of rigid motion in newborns' face recognition

The study investigated whether dynamic information promotes newborns' ability to recognize a face. After being habituated to a face undergoing an ordered sequential head rigid motion (Exp. 1), 1- to 3-day-old newborns fully recognized the familiar face shown in the profile pose, as documented by a preference for the profile pose of a novel face. When familiarized to an ordered sequence of different viewpoint static images of a face (Exp. 2), newborns failed to recognize the profile pose of the familiar face, their visual exploration of the familiar and novel faces being at chance. Habituation to a random head rigid motion (Exp. 3) allowed only a partial recognition of face identity, as newborns preferred the profile pose of the familiar, rather than the novel, face. Rigid head motion is an important source of information for newborns' face recognition, probably aiding the derivation of a three-dimensional face structure.     

The role of motion and speech in face recognition at birth

Newborns, a few hours after birth, already encounter many different faces, talking or silently moving. How do they process these faces and which cues are important in early face recognition? In a series of six experiments, newborns were familiarized with an unfamiliar face in different contexts (photographs, talking, silently moving, and with only external movements of the head with speech sound). At test, they saw the familiar and a new faces either in photographs, silently moving, or talking. A novelty preference was evidenced at test when photographs were presented in the two phases. This result supports those already evidenced in several studies. A familiarity preference appeared only when the face was seen talking in the familiarization phase and in a photograph or talking again at test. This suggests that the simultaneous presence of speech sound, and rigid and nonrigid movements present in a talking face enhances recognition of interactive faces at birth.     

The effects of precedence on Navon-induced processing bias in face recognition

Macrae and Lewis (2002) Macrae, C. N. and Lewis, H. L. 2002. Do I know you? Processing orientation and face recognition. Psychological Science, 13: 194–196. [Crossref], [PubMed], [Web of Science ®] , [Google Scholar] showed that repeated reporting of the global dimension of Navon stimuli improved performance in a subsequent face identification task, whilst reporting the features of the Navon stimuli impaired performance. Using a face composite task, which is assumed to require featural processing, Weston and Perfect (2005) Weston, N. J. and Perfect, T. J. 2005. The effects of processing bias on the composite effect. /precode>. Psychonomic Bulletin and Review, 12: 1038–1042. [Crossref], [PubMed], [Web of Science ®] , [Google Scholar] showed the complementary pattern: Featural responding to Navon letters speeded performance. However, both studies used Navon stimuli with global precedence, in which the overall configuration is easier to report than the features. Here we replicate the two studies above, whilst manipulating the precedence (global or featural) of the letter stimuli in the orientation task. Both studies replicated the previously reported findings with global precedence stimuli, but showed the reverse pattern with local precedence stimuli. These data raise important questions as to what is transferred between the Navon orientation task and the face-processing tasks that follow.     

The underlying structure of the Beck Depression Inventory II: A multidimensional scaling approach

The purpose of the present study was to confirm Beck’s six symptom categorization of depression through the most recent version of Beck Depression Inventory (BDI-II) by employing a confirmatory multidimensional scaling (MDS). This analysis indicates two independent dimensions in the BDI-II. The disturbance domain dimension relates to the domains wherein the disturbances occur, and validates Beck’s six symptom categorization dividing the items into disturbances in basic need-satisfaction, energy regulation, focused attention, regulation of emotion, motivation, and cognitive distortion in self-evaluation. The level of arousal dimension relates to how the disturbances are expressed, namely in an under-active, regular, or over-active manifestation. The MDS solution suggests 18 (6 × 3) symptom areas of depression, and may serve as a guide for constructing additional items.     

The contribution of shape and surface information in the other-race face effect

Faces from another race are generally more difficult to recognize than faces from one's own race. However, faces provide multiple cues for recognition and it remains unknown what are the relative contribution of these cues to this “other-race effect”. In the current study, we used three-dimensional laser-scanned head models which allowed us to independently manipulate two prominent cues for face recognition: the facial shape morphology and the facial surface properties (texture and colour). In Experiment 1, Asian and Caucasian participants implicitly learned a set of Asian and Caucasian faces that had both shape and surface cues to facial identity. Their recognition of these encoded faces was then tested in an old/new recognition task. For these face stimuli, we found a robust other-race effect: Both groups were more accurate at recognizing own-race than other-race faces. Having established the other-race effect, in Experiment 2 we provided only shape cues for recognition and in Experiment 3 we provided only surface cues for recognition. Caucasian participants continued to show the other-race effect when only shape information was available, whereas Asian participants showed no effect. When only surface information was available, there was a weak pattern for the other-race effect in Asians. Performance was poor in this latter experiment, so this pattern needs to be interpreted with caution. Overall, these findings suggest that Asian and Caucasian participants rely differently on shape and surface cues to recognize own-race faces, and that they continue to use the same cues for other-race faces, which may be suboptimal for these faces.     

Recognition of facial expression and identity in part reflects a common ability,independent of general intelligence and visual short-term memory

Recognising identity and emotion conveyed by the face is important for successful social interactions and has thus been the focus of considerable research. Debate has surrounded the extent to which the mechanisms underpinning face emotion and face identity recognition are distinct or share common processes. Here we use an individual differences approach to address this issue. In a well-powered (N?=?605) and age-diverse sample we used structural equation modelling to assess the association between face emotion recognition and face identity recognition ability. We also sought to assess whether this association (if present) reflected visual short-term memory and/or general intelligence (g). We observed a strong positive correlation (r?=?.52) between face emotion recognition ability and face identity recognition ability. This association was reduced in magnitude but still moderate in size (r?=?.28) and highly significant when controlling for measures of g and visual short-term memory. These results indicate that face emotion and face identity recognition abilities in part share a common processing mechanism. We suggest that face processing ability involves multiple functional components and that modelling the sources of individual differences can offer an important perspective on the relationship between these components.     

Cross-modal integration of emotional face and voice in congruous and incongruous pairs: The P2 ERP effect

The study investigates cross-modal simultaneous processing of emotional tone of voice and emotional facial expression by event-related potentials (ERPs), using a wide range of different emotions (happiness, sadness, fear, anger, surprise, and disgust). Auditory emotional stimuli (a neutral word pronounced in an affective tone) and visual patterns (emotional facial expressions) were matched in congruous (the same emotion in face and voice) and incongruous (different emotions) pairs. Subjects (N=31) were required to watch and listen to the stimuli in order to comprehend them. Repeated measures ANOVAs showed a positive ERP deflection (P2), more posterior distributed. This P2 effect may represent a marker of cross-modal integration, modulated as a function of congruous/incongruous condition. Indeed, it shows an ampler peak in response to congruous stimuli than incongruous ones. It is suggested P2 can be a cognitive marker of multisensory processing, independently from the emotional content.