Three- to 4-month-old infants reared by female caregivers display a spontaneous preference for individual adult women’s over men’s faces. Here we report that this preference extends to prototype girl over boy faces. The findings suggest transfer of gender-diagnostic facial information from individual adult to prototype child faces.

A comparison of the literatures on how infants categorize generic object classes, gender and race information in faces, and emotional expressions reveals both common and distinctive developments in the three domains. In addition, the review indicates that some very basic questions remain to be answered regarding how infants represent facial displays of emotion, including (1) whether infants form category representations for discrete classes of emotion, (2) when and how such representations come to incorporate affective meaning, (3) the developmental trajectory for representation of emotional expression at different levels of inclusiveness (i.e. from broad to narrow or narrow to broad?), and (4) whether there is superior discrimination ability operating within more frequently experienced emotion categories.

PRIMARY OBJECTIVE: Difficulties with attention contribute to behavioural and cognitive problems during childhood and may reflect subtle deficits in executive functioning (EF). Attention problems in early childhood have also been found to predict higher levels of anxiety and depression symptoms at 10 years old. It has also been reported that attention problems during childhood may be differentially related to later-emerging distinct EF difficulties. Many of these findings, however, rely on teacher-ratings of attention difficulties. METHODS AND PROCEDURES: This study administered neuropsychological tests of attention-switching and EF to 67 healthy children aged 9-15 years of age. It additionally measured socio-emotional behavioural functioning. MAIN OUTCOMES AND RESULTS: a critical phase of improvement was found at 10 years of age. Correlations were found between attention-switching skills and EF. Attention-switching skills were also correlated with socio-emotional functioning. CONCLUSIONS: Attention-switching skills have some interdependence with EF, but in paediatric assessment such skills are easier to routinely assess than many of the currently available tests of EF. It is suggested that attention-switching ability may prove to be a useful predictor of EF performance in understanding long-term outcome after a neurological event such as traumatic brain injury.

Children with traumatic brain injuries (TBI) commonly present with socioemotional difficulties, as well as accompanying multiple cognitive impairments. Often difficulties worsen at around 10 years old. This change is associated with frontal system changes, and tests of executive function (EF) predict outcome. However, children with TBI sometimes present with socioemotional difficulties despite apparent cognitive recovery. Our aims were to explore potential cognitive and socioemotional effects following childhood TBI, before and after the age of 10 years. We also wanted to identify cognitive correlates of psychosocial dysfunction. Measures of cognitive function and socioemotional disturbance administered to 14 children with TBI aged 8-10 years, and 14 children with TBI aged 10-16 years, were compared to control data from 22 non-injured 8- to 10 year-olds and 67 non-injured 10- to 16-year-olds. Results indicated that only the older group of children with TBI were impaired in tests of EF, but significant socioemotional difficulties were commonly evident in both groups. Processing speed (as well as EF) was found to correlate with socioemotional disturbance. We conclude that poor processing speed may also index the risk of socioemotional difficulties, but our general findings indicate that cognitive functions relevant to socioemotional functioning are not readily testable in younger children and are not strongly associated with such outcomes as they may be in adults.

Experience plays a crucial role in the development of the face processing system. At 6 months of age infants can discriminate individual faces from their own and other races. By 9 months of age this ability to process other-race faces is typically lost, due to minimal experience with other-race faces, and vast exposure to own-race faces, for which infants come to manifest expertise [1]. This is known as the Other Race Effect. In the current study, we demonstrate that exposing Caucasian infants to Chinese faces through perceptual training via picture books for a total of one hour between 6 and 9 months allows Caucasian infants to maintain the ability to discriminate Chinese faces at 9 months of age. The development of the processing of face race can be modified by training, highlighting the importance of early experience in shaping the face representation. © 2011 Heron-Delaney et al.

PRIMARY OBJECTIVE: Acquired brain injury (ABI) during childhood can be associated with enduring difficulties related to impairments to executive functioning (EF). EF impairments may detrimentally affect outcome by restricting an individual's ability to access 'resiliency' resources after ABI. RESEARCH DESIGN: the purpose of this study was to explore whether there is deterioration in children's resilience compared with peers after ABI and whether EF is influential in mediating relationships between resilience and behaviour. METHODS AND PROCEDURES: Measures of resilience, depression and anxiety were administered with 21 children with ABI and 70 matched healthy children aged 9-15 years. Parents completed measures of behaviour and EF. MAIN OUTCOMES AND RESULTS: Children with ABI were identified as less resilient and more depressed and anxious than controls. Resiliency measures were correlated with depression and anxiety in both groups. Relationships between resiliency and socio-emotional behaviour were mediated by EF. CONCLUSIONS: Assessment of resilience after ABI may be useful in supporting or defining the delivery of more individualized rehabilitation programmes according to the resources and vulnerabilities a young person has. However, an accurate understanding of the role of EF in the relationship between resilience and behavioural outcome after ABI is essential.

The present study examined whether 6- and 9-month-old Caucasian infants could categorize faces according to race. In Experiment 1, infants were familiarized with different female faces from a common ethnic background (i.e. either Caucasian or Asian) and then tested with female faces from a novel race category. Nine-month-olds were able to form discrete categories of Caucasian and Asian faces. However, 6-month-olds did not form discrete categories of faces based on race. In Experiment 2, a second group of 6- and 9-month-olds was tested to determine whether they could discriminate between different faces from the same race category. Results showed that both age groups could only discriminate between different faces from the own-race category of Caucasian faces. The findings of the two experiments taken together suggest that 9-month-olds formed a category of Caucasian faces that are further differentiated at the individual level. In contrast, although they could form a category of Asian faces, they could not discriminate between such other-race faces. This asymmetry in category formation at 9 months (i.e. categorization of own-race faces vs. categorical perception of other-race faces) suggests that differential experience with own- and other-race faces plays an important role in infants' acquisition of face processing abilities. © 2009 the Authors. Journal compilation © 2009 Blackwell Publishing Ltd.

Stimulation of one sensory modality can induce perceptual experiences in another modality that reflect synaesthetic correspondences among different dimensions of sensory experience. In visual-hearing synaesthesia, for example, higher pitched sounds induce visual images that are brighter, smaller, higher in space, and sharper than those induced by lower pitched sounds. Claims that neonatal perception is synaesthetic imply that such correspondences are an unlearned aspect of perception. To date, the youngest children in whom such correspondences have been confirmed with any certainty were 2- to 3-year-olds. We examined preferential looking to assess 3- to 4-month-old preverbal infants' sensitivity to the correspondences linking auditory pitch to visuospatial height and visual sharpness. The infants looked longer at a changing visual display when this was accompanied by a sound whose changing pitch was congruent, rather than incongruent, with these correspondences. This is the strongest indication to date that synaesthetic cross-modality correspondences are an unlearned aspect of perception. © the Author(s) 2010.

Face perception remains one of the most intensively researched areas in psychology and allied disciplines and there has been much debate regarding the early origins and experiential determinants of face processing. This article reviews studies, the majority of which have appeared in the last decade, which discuss possible mechanisms underlying face perception at birth and which document the prominent role of experience in shaping infants’ face processing abilities. In the first months of life, infants develop a preference for female and own-race faces, and become better able to recognise and categorize own-race and own-species faces. This perceptual narrowing and shaping of the “face space” forms a foundation for later face expertise in childhood and adulthood, and testifies to the remarkable plasticity of the developing visual system.

After a brief familiarization period to either one or two toys 5-month-olds gave a clear preference for perceptually novel displays, suggesting that replicable findings of greater looking at an unexpected arithmetic outcome in addition/subtraction experiments cannot easily be attributed to simple familiarity preferences.

The other-race effect in face processing develops within the first year of life in Caucasian infants. It is currently unknown whether the developmental trajectory observed in Caucasian infants can be extended to other cultures. This is an important issue to investigate because recent findings from cross-cultural psychology have suggested that individuals from Eastern and Western backgrounds tend to perceive the world in fundamentally different ways. To this end, the current study investigated 3-, 6-, and 9-month-old Chinese infants' ability to discriminate faces within their own racial group and within two other racial groups (African and Caucasian). The 3-month-olds demonstrated recognition in all conditions, whereas the 6-month-olds recognized Chinese faces and displayed marginal recognition for Caucasian faces but did not recognize African faces. The 9-month-olds' recognition was limited to Chinese faces. This pattern of development is consistent with the perceptual narrowing hypothesis that our perceptual systems are shaped by experience to be optimally sensitive to stimuli most commonly encountered in one's unique cultural environment. © 2009 Elsevier Inc.

Lasting socio-emotional behaviour difficulties are common among children who have suffered brain injuries. A proportion of difficulties may be attributed to impaired cognitive and/or executive skills after injury. A recent and rapidly accruing body of literature indicates that deficits in recognizing and responding to the emotions of others are also common. Little is known about the development of these skills after brain injury. In this paper we summarize emotion-processing systems, and review the development of these systems across the span of childhood and adolescence. We describe critical phases in the development of emotion recognition skills and the potential for delayed effects after brain injury in earlier childhood. We argue that it is important to identify the specific nature of deficits in reading and responding to emotions after brain injury, so that assessments and early intervention strategies can be devised.

The other-race effect is a collection of phenomena whereby faces of one's own race are processed differently from those of other races. Previous studies have revealed a paradoxical mirror pattern of an own-race advantage in face recognition and an other-race advantage in race-based categorisation. With a well-controlled design, we compared recognition and categorisation of own-race and other-race faces in both Caucasian and Chinese participants. Compared with own-race faces, other-race faces were less accurately and more slowly recognised, whereas they were more rapidly categorised by race. The mirror pattern was confirmed by a unique negative correlation between the two effects in terms of reaction time with a hierarchical regression analysis. This finding suggests an antagonistic interaction between the processing of face identity and that of face category, and a common underlying processing mechanism. © 2009 a Pion publication.

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. © 2008 Elsevier Inc. All rights reserved.

Several studies have shown that participants, without a deficit in face recognition, give an increased skin conductance response (SCR) to familiar faces when presented subliminally, hence suggesting covert recognition of these faces. In the experiment presented here we manipulated familiarity and attractiveness and tested whether participants distinguished between faces for these variables when presented too fast to allow conscious recognition. Three sets of faces were presented: famous attractive; unfamiliar attractive; and unfamiliar less attractive. SCRs were the same for each category of faces whether presented subliminally or supraliminally, and were the same for attractive faces, whether famous or unfamiliar; however, SCRs differed between the attractive and less attractive faces. The findings support those of Stone et al (2001 Cognitive, Affective and Behavioral Neuroscience 1 183-191) and suggest that higher SCRs to famous faces are not necessarily due to covert recognition, but may be a response to the positive affective valence of the stimuli.

PRIMARY OBJECTIVE: a previous study has shown that children with brain injuries are worse than their same age peers at reading emotions. It has not clearly been established that cognitive impairments and emotion processing impairments are dissociable in children and the question of whether emotion-reading skills can be selectively impaired in children after brain injury is explored here. RESEARCH DESIGN: This study addresses this issue by testing a case series of seven children with brain injuries, who were identified as experiencing emotional or behavioural difficulties, according to a social-behavioural measure. METHODS AND PROCEDURES: a battery of tests of cognitive function and measures that assess ability in reading emotions from faces, voices and eyes was administered to each child. MAIN OUTCOMES AND RESULTS: Some cases demonstrate broadly based deficits that affect both cognitive and emotion processing domains, whilst other cases demonstrate highly selective deficits in reading emotions. CONCLUSIONS: Based on the profile of results across the cases, this study reports that modality-specific, selective impairments in reading emotional expression can be found in children after brain injury. In addition, the data provide evidence of dissociation between cognitive abilities and emotional expression processing.

PRIMARY OBJECTIVE: Child brain injury can have a lasting, detrimental effect upon socio-emotional behaviour, but little is known about underlying impairments that cause behavioural disturbance. This study explored the possibility that a proportion of difficulties result from compromise to systems in the brain which function in reading emotion in others from eyes, face expression or vocal tone. METHODS AND PROCEDURES: Measures of ability in reading emotion from faces, voices and eyes were used in conjunction with a battery of tests of cognitive function, in gathering data from 18 children aged between 9-17 with acquired brain injuries (ABI). Performance levels were compared against the normative data from 67 matched 'healthy' children. Questionnaires were used as a measure of socio-emotional behaviour. MAIN OUTCOMES AND RESULTS: the ABI children in the sample were worse than their same age peers at reading emotions. Regression analyses revealed that emotion recognition skills and cognitive abilities were generally unrelated. Some relationships between emotion reading difficulties and behaviour disturbance were found, however there were limitations associated with this particular finding. CONCLUSIONS: Emotion-recognition skills, which are not routinely assessed following child brain injury, can be adversely affected as a consequence of brain injury in childhood.

The ability of 3-month-old infants to learn arbitrary auditory -visual associations between voices and faces was investigated by familiarizing each infant to two alternating stimuli presented on a VCR monitor. Each stimulus was a voice-face combination, where the voices and faces were male and/or female. On the post-familiarization test trials each infant was presented alternately with a familiar and a novel voice-face combination, where the novel combination consisted of a voice and a face they had heard and seen previously (but not together), and on these test trials attention was significantly higher to the novel combination. These findings are a clear demonstration that 3-month-olds can learn arbitrary voice-face associations, and they are discussed in terms of early intermodal perception and face perception. Copyright © 2001 John Wiley & Sons, Ltd.

Relations between cognitive development in infancy and early childhood, and parental education were examined. Previous research has found little association between measures of the parenting environment, including parental education and socio-economic status (SES), and cognitive development in infants and children under 2 years of age. However, the earliest studies may not have reliably measured individual differences in cognitive abilities, thus, there is uncertainty as to what age elements in the parental environment affect cognitive development. Seventy-six infants were tested on a range of cognitive tasks at 3-month intervals between the ages of 9 and 18 months. Information on parental education (a component of SES) was collected. Seventy-one of the children returned at 27 months and completed the Bayley Scales of Infant Development, Mental Scale, which was used as an outcome measure for the earlier tasks. The findings present a clear indication that cognitive development in early childhood is affected by the parenting environment, at least from as early as 12 months. Copyright © 1999 John Wiley & Sons, Ltd.

Three experiments were conducted to determine whether human observers could identify the gender of 40 domestic cats (20 female, 20 male) depicted in individual color photographs. In experiment 1a, observers performed at chance for photographs depicting whole cats, cat heads (bodies occluded), and cat bodies (heads occluded). Experiment 1b showed that chance performance was also obtained when the photographs were full-face close-ups of the cats. Experiment 2a revealed that even with gender-identification training on 30 (15 female, 15 male) of the 40 face close-ups, observers were unable to generalize their training to reliably identify the gender of the 10 remaining test faces (5 female, 5 male). However, experiment 2b showed that gender-identification training with the 14 most accurately identified faces from experiment 1b (7 female, 7 male) was successful in raising gender identification of the 10 test faces above chance. Experiments 3a and 3b extended this facilitative effect of gender-identification training to a population of animal-care workers. The findings indicate that, with appropriate training, human observers can identify the gender of cat faces at an above-chance level. A perceptual category learning account emphasizing the on-line formation of differentiated male versus female prototypes during training is offered as an explanation of the findings.

In this study the ability of newborn infants to learn arbitrary auditory-visual associations in the absence versus presence of amodal (redundant) and contingent information was investigated. In the auditory-noncontingent condition 2-day-old infants were familiarized to two alternating visual stimuli (differing in colour and orientation), each accompanied by its 'own' sound: when the visual stimulus was presented the sound was continuously presented, independently of whether the infant looked at the visual stimulus. In the auditory-contingent condition the auditory stimulus was presented only when the infant looked at the visual stimulus: thus, presentation of the sound was contingent upon infant looking. On the post-familiarization test trials attention recovered strongly to a novel auditory-visual combination in the auditory-contingent condition, but remained low, and indistinguishable from attention to the familiar combination, in the auditory-noncontingent condition. These findings are a clear demonstration that newborn infants' learning of arbitrary auditory-visual associations is constrained and guided by the presence of redundant (amodal) contingent information. The findings give strong support to Bahrick's theory of early intermodal perception.

Several previous experiments have found that infants 2 months of age and older will spend more time looking at attractive faces when these are shown paired with faces judged by adults to be unattractive. Two experiments are described whose aim was to find whether the "attractiveness effect" is present soon after birth. In both, pairings of attractive and unattractive female faces (as judged by adult raters) were shown to newborn infants (in the age range 14-151 hours from birth), and in both the infants looked longer at the attractive faces. These findings can be interpreted either in terms of an innate perceptual mechanism that detects and responds specifically to faces, or in terms of rapid learning about faces soon after birth. © 1998 Ablex Publishing Corporation.

Most of the stimuli that we experience are intermodal in that they provide information to more than one sensory modality. Some of these intermodal relationships are amodal in that they provide equivalent information to the senses, while others are quite arbitrary. For instance, there is no information specifying that a particular voice has to be associated with a particular face, or that a particular animal makes a particular sound. The ability of newborn infants to learn arbitrary visual-auditory associations was investigated by familiarizing 2-day-old infants to two alternating visual stimuli (differing in colour and orientation), each accompanied by its 'own' sound. On post-familiarization test trials attention recovered to a novel visual-auditory combination. These findings are a clear demonstration that newborn infants can learn arbitrary visual-auditory associations, and they are discussed in terms of Bahrick's theory of early intermodal perception. ©1997 John Wiley & Sons, Ltd.

Purpose. Blurring an image results in both a reduction in contrast, as defined by an attenuation of the Fourier components of high spatial frequencies, as well as a gradual change in the luminance profile of the stimulus. These studies address whether 1) infants demonstrate a preference for clear images over blurred ones, and if so, 2) is this due to the change in contrast or luminance profile. Methods. Experiment 1. Complex images were used in the first experiment to investigate whether infants do in fact demonstrate a preference for clear stimuli over their blurred analogs. Six clear black and white clip-art images were paired with the same images blurred using a Gaussian filter with standard deviations of 0.5, 1.0 and 1.5 cycles/degrees. Seventeen infants ranging from 3-8 months of age were tested using a preferential looking paradigm to assess infant preference. Experiment 2 explored whether infant preference for clear images can be explained by the higher contrast of the clear stimuli. The contrast of three of the original clear images was reduced by equating mean amplitude with those stimuli blurred with a 1.5 cycle/degree filter. The space averaged luminance was kept the same for both clear and filtered images. The contrast-equated clear stimuli were then paired with the 1.5 cycle/deg blurred stimuli and presented to eight infants in a preferential looking paradigm. Results. The first experiment showed that infants looked at 4 of the 6 stimuli significantly longer than 50% of the time (p

Newborn infants were familiarized to a display which contained multiple cues that specified the completeness or coherence of a partly concealed object. However, the findings from test trials suggested that object unity had not been perceived. Possible reasons for the newborn's limitations, and of age changes in perception of object unity, are discussed.

Newly hatched chicks (Gallus gallus) were imprinted on a display consisting of two rod pieces that moved above and below a central occluder. On test trials, the chicks approached a complete rod in preference to two rod pieces. This finding, supported by those from control coditions, suggests that chicks, soon after hatching, perceive object unity. The results are compared with those from human infants. © 1996 Ablex Publishing Corporation.

In recent years it has been demonstrated that cognitive development from infancy to later childhood displays some degree of (correlational) continuity. Studies that have demonstrated this continuity are reviewed, focusing on measures of visual information processing, means-ends problem-solving and other cognitive indices of infant performance. Models of continuity are described and evaluated, and the relevance of the findings and models to the Nature-Nurture issue are considered, with particular attention to the related issues of the role of experience in early life, and the extent to which infant development is canalized. Theoretical and practical applications of the research are discussed.

AIMS: a study was carried out to compare the visual abilities of prematurely born children with those of matched full term controls. METHODS: the vision of 68 children born at less than 32 weeks' gestation and aged between 5 and 7 1/2 years at the time of testing was compared with that of a control group of children born at full term, and matched for sex and age from due date. RESULTS: the premature children had significantly poorer distance and near visual acuity, contrast sensitivity and stereopsis, and a high incidence of colour vision defects (predominantly tritan type). These differences were associated with the high incidence of ocular pathology experienced by 31 (45%) of the premature children compared with only nine (13%) of the controls. When excluding children with ocular and cerebral pathology, 32 matched pairs of premature and control children remained. The 32 premature children did not differ from their controls in terms of distance and near acuities or stereopsis, but they did have significantly poor contrast sensitivity in both their 'best' and 'worst' eyes. None of the 32 control children had colour vision defects, compared with seven of the matched premature children. CONCLUSION: This adds support to previous speculation that the preterm eye is at risk of subtle visual impairment independent of the occurrence of refractive error, manifest squint, disorders of the fundus and media, and cerebral damage.

Cohen (1988; Cohen & Younger, 1984) has suggested that there is a shift in the perception of form sometime after 6 weeks of age. Prior to this age infants can remember the specific orientations of line segments, but cannot process and remember the angular relations that line segments can make. Experiment 1 used simple line stimuli with newborn infants to test this suggestion. Following habituation to a simple two-line angle the newborns dishabituated to a change of orientation but not to a change in angle, confirming Cohen and Younger's suggestion that orientation is a powerful cue in early shape perception. In Experiments 2 and 3 newborns were familiarized either to an acute or to an obtuse angle that changed its orientation over trials. On subsequent test trials the babies gave strong novelty preferences to a different angle. Alternative interpretations of the results are discussed, but these experimental findings are compatible with the suggestion that newborns can quickly learn to process angular relations, and that rudimentary form perception may not be dependent on a lengthy period of learning and/or maturation for its development.

An experiment is described in which newborn infants' processing of stimulus compounds was investigated. After familiarization to two alternately presented stimuli which differed in colour and orientation, the newborns showed significant preferences for a stimulus which had a novel colour/orientation combination: the novel stimulus was produced by recombining features of the stimuli used for familiarization. This finding argues against the view that infants initially process separate components, or parts, of visual stimuli and are only able to attend to the correlations between them after about 3 months of age. Rather, the ability to process and remember stimulus compounds is present at birth.

In experiments described by Kellman and Spelke (1983) and Kellman, Spelke, and Short (1986), 4-month-old infants were habituated to a stimulus (usually a rod) which moved behind a central occluder, so that only the top and bottom of the rod was visible. Subsequently, the infants increased responding to a stimulus consisting of two object pieces with a gap where the occluding block had been but did not respond to a continuous rod, suggesting that during the habituation trials, they had been perceiving a connected object, that is, they were "filling in" the unseen portion. The present article describes five experiments which were designed to see if perception of object unity is present at birth. In Experiments 1, 2, and 5, moving, occluded displays were shown to newborn infants. In Experiment 1, the familiarized stimulus was an outline square which underwent translatory motion behind a stationary occluder, and in Experiments 2 and 5, the familiarized stimulus was a rod which moved back and forth behind a stationary occluder. In all three experiments, the newborns subsequently gave a strong preference for a continuous, rather than a broken, stimulus. Experiments 3 and 4 showed, respectively, that newborns perceive both moving and stationary parts of a moving, occluded display, and that the preferences found in Experiments 1, 2, and 5 are best interpreted as novelty, rather than familiarity, preferences. In striking contrast to the above, in Experiment 5, 4-month-old infants, tested under the same conditions as the newborn infants, gave a strong novelty preference for two object pieces rather than a continuous stimulus, a finding which replicates the results of Kellman et al. (1986). These findings argue against the view that infants begin life with a knowledge of the unity and coherence of objects and suggest that infants' understanding of objects changes in the early months of life. Unlike 4-month-olds, newborns appear to perceive only that which is immediately visible, and they seem to be unable to make perceptual inferences from visual input. © 1990.

Two experiments are described whose aim was to investigate whether perception of size at birth is determined solely by proximal (retinal) stimulation, or whether newborn babies have the ability to perceive an object's real size across changes in distance. In Experiment 1, preferential looking between pairs of stimuli which varied in real size and viewing distance was found to be solely determined by retinal size, suggesting that changes to proximal stimulation can have profound effects on newborns' looking behavior. However, in Experiment 2 newborns were desensitized to changes in distance (and retinal size) during familiarization trials, and subsequently strongly preferred a different sized object to the familiar one, suggesting that the real size had been perceived as constant across the familiarization trials. These results confirm Granrud's (1987) findings that size constancy is present at birth.

There is some controversy concerning whether or not the visual abilities of the newborn are mediated entirely through subcortical pathways or whether the visual cortex is functioning at birth. A critical test of cortical functioning is discrimination of orientation: orientation-selective neurons are found in the visual cortex but not in subcortical parts of the visual system. An experiment is described in which newborn infants were habituated to a square-wave grating oriented 45 degrees from vertical. After habituation, significant preferences for the novel, mirror-image, grating were found, a result which argues for some degree of visual cortical functioning at birth.

The present study investigated whether measures of habituation and dishabituation in early infancy predicted later(age 4 1 2 years) intelligence. An infant-controlled habituation procedure was used and each infant was tested on three separate occasions. Statistically reliable correlations between the two ages were obtained, and these were specific to: (a) verbal components of the child intelligence test scores; (b) measures derived from the familiarization of habituation phase of the infant testing, rather than from subsequent dishabituation or novelty response scores. The predictive infant measures were only those which minimally satisfied both of two psychometric criteria: (1) There are consistent changes with age; (2) there is test-retest reliability, with age partialled out. The results are compared with those from other comparable studies, and it is argued that the psychometric acceptability of infant cognitive measures needs to be demonstrated before they can be considered to be potential predictors. © 1986.

Three experiments are described which relate to models of infant visual preferences, and to the ways in which preferences can be modified or created by habituation. In all experiments newborn babies were used as subjects. In Experiments 1 and 2 infants were presented with pairs of stimuli that were equated for contour density but which differed in spatial frequency components. The preferences obtained give support to Banks and Salapatek's (1981, Journal of Experimental Child Psychology, 31, 1-45) model of infant preferences which predicts that the maximally preferred stimulus will be that which contains high amplitude spatial frequency components falling within the age group's peak contrast sensitivity. In Experiment 3 an infant-controlled habituation procedure was used. The results obtained suggest that strong natural preferences based on the infants' peak contrast sensitivity cannot be changed by habituating infants either to the preferred or to the nonpreferred member of a stimulus pair. However, where no prior preference exists between two stimuli that are perceptually highly discriminable, very strong novelty preferences are found after habituating newborns to either stimulus. The results suggest that the contrast sensitivity model can be a powerful predictor of preferential looking in newborns, and in addition are further evidence that preferences based on experience can be found from birth. © 1985.

Four experiments are described in which the newborn's ability to habituate to a visual stimulus and subsequently to display novelty/familiarity preferences was explored. The same two types of stimuli, simple geometric shapes and complex colored patterns, were used throughout. The results suggest that newborns will reliably give novelty preferences when an infant-controlled habituation procedure is used. However, no reliable preferences emerged following either a brief exposure to a stimulus, or when novel and familiar stimuli were presented paired together over several trials. In experiment 4 different, novel stimuli were presented on successive infant-controlled trials and the decline in trial length observed during habituation trials was not found. Although this is further evidence that habituation to a repeated visual stimulus does occur in the newborn, half of the subjects in experiment 4 would have met the infant-controlled criterion of habituation: these results are discussed in terms of artifacts that can affect habituation. While there is considerable intra-and intersubject variability in trial duration, and in other dependent measures, the results give support to the model of habituation which assumes it to be an exponentially decreasing process. © 1985 Ablex Publishing Corporation.

Three experiments are reported in which the newborn baby's ability to fixate binocularly was investigated, using the corneal reflection technique for measuring eye fixation position. Two criteria for consistent binocular fixation were assessed. These are (1) the two eyes will be optically more divergent when fixating more distant targets, and (2) each eye will be scored as being on-target when corrections for the expected deviations of the pupil center from the fixated stimulus are introduced. In the first experiment vertical arrays of lights were separately shown at distances of 10 and 20 in. from the subjects' eyes (with the retinal image size and luminance of the stimuli held constant). The 12 newborns who gave results at both viewing distances reliably converged to both stimuli, the optical divergence of the pupil centers of the eyes increasing with presentation of the more distant stimulus. In Expt 2 similar stimuli at 5 and 10 in. from the eyes were shown. It was again the case that the subjects reliably converged to the stimulus at 10 in. This was no so for the stimulus at 5 in. and many subjects fixated this stimulus with monocular vision. The failure to converge is probably due to an inability to accommodate to this near distance. In Expt 3 different stimuli (a vertical strip of light, an outline triangle and square, and an array of squares) were presented a constant distance (10 ± 1 in.) from the eyes. The majority of the 15 subjects binocularly fixated all three stimuli: for those subjects who failed to converge consistently to these stimuli the observed alternatives to binocular fixation were monocular fixation, divergent strabismus, and a third category of response that is most probably an indication of inattention to the stimulus. It can be concluded that the newborn baby possesses the ability to fixate binocularly an appropriately presented stimulus, and has the basic requirements for binocular vision. © 1975.

Corneal reflection techniques for eye fixation position measurement have been used in recent years to assess such variables of visual behavior as duration of looking and the area(s) of the stimulus fixated. These techniques are especially useful when measuring visual regard in infants and young children as head restraints are not required. In an earlier article the present authors demonstrated, empirically, that the common assumption that the center of the pupil represents the line of sight is untenable. The present article considers the causes of the errors present in these techniques: it can be shown that theoretical calculations of these sources of error, calculations based both on the anatomy of the eye, and on the optics involved, produce good agreement with their empirically derived magnitudes. © 1975.

The estimation of eye fixation position in the adult and neonate by means of the corneal reflection method was investigated. It is shown that estimation of line of sight using the point of the target whose image coincides with the pupil center is unsatisfactory unless certain corrections are made. Even when the subject fixates close to the axis of observation the inclination of the visual axis to the optic axis in the eye must be taken into account. This entails a correction of 5° visual angle or more. In cases where there is an angle between the observation axis and the subject's fixation axis, further deviations are found of up to 5° in adults and up to 10° in neonates. It is believed that these effects may account for reports of off-target looking and nonconvergence in neonates. © 1972.