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Abstract Research using the visual paired comparison task has shown that visual recognition memory across changing contexts is dependent on the integrity of the hippocampal formation in human adults and in monkeys. The acquisition of contextual flexibility may contribute to the change in memory performance that occurs late in the first year of life. To assess this skill, the images are presented on a background of one colour during familiarization and on a different coloured background during the recognition test. Our research showed that recognition memory is impaired by a change in context at 6 and 12 months of age but is unaffected at 18 and 24 months of age. The findings are discussed in relation to hippocampal development and the proposed developmental step in memory at 9–10 months of age.

AbstractThis study investigated peripheral vision (at least 30° eccentric to fixation) development in profoundly deaf children without cochlear implantation, and compared this to age‐matched hearing controls as well as to deaf and hearing adult data. Deaf and hearing children between the ages of 5 and 15 years were assessed using a new, specifically paediatric designed method of static perimetry. The deaf group (N = 25) were 14 females and 11 males, mean age 9.92 years (range 5–15 years). The hearing group (N = 64) were 34 females, 30 males, mean age 9.13 years (range 5–15 years). All participants had good visual acuity in both eyes (< 0.200 LogMAR). Accuracy of detection and reaction time to briefly presented LED stimuli of three light intensities, at eccentricities between 30° and 85° were measured while fixation was maintained to a central target. The study found reduced peripheral vision in deaf children between 5 and 10 years of age. Deaf children (aged 5–10 years) showed slower reaction times to all stimuli and reduced ability to detect and accurately report dim stimuli in the far periphery. Deaf children performed equally to hearing children aged 11–12 years. Deaf adolescents aged 13–15 years demonstrated faster reaction times to all peripheral stimuli in comparison to hearing controls. Adolescent results were consistent with deaf and hearing adult performances wherein deaf adults also showed significantly faster reaction times than hearing controls. Peripheral vision performance on this task was found to reach adult‐like levels of maturity in deaf and hearing children, both in reaction time and accuracy of detection at the age of 11–12 years.

AbstractInfants can form object categories based on perceptual cues, but their ability to form categories based on differential experience is less clear. Here we examined whether infants filter through perceptual differences among faces from different other‐race classes and represent them as a single other‐race class different only from own‐race faces. We used a familiarization/novelty‐preference procedure to investigate category formation for two other‐race face classes (Black vs. Asian) by White 6‐ and 9‐month‐olds. The data indicated that while White 6‐month‐olds categorically represented the distinction between Black and Asian faces, White 9‐month‐olds formed a broad other‐race category inclusive of Black and Asian faces, but exclusive of own‐race White faces. The findings provide evidence that narrowing can occur for mental processes other than discrimination: category formation is also affected. The results suggest that frequency of experience with own‐race versus other‐race classes of faces may propel infants to contrast own‐race faces with other‐race faces, but not different classes of other‐race faces with each other.

AbstractInfants respond preferentially to faces and face‐like stimuli from birth, but past research has typically presented faces in isolation or amongst an artificial array of competing objects. In the current study infants aged 3‐ to 12‐months viewed a series of complex visual scenes; half of the scenes contained a person, the other half did not. Infants rapidly detected and oriented to faces in scenes even when they were not visually salient. Although a clear developmental improvement was observed in face detection and interest, all infants displayed sensitivity to the presence of a person in a scene, by displaying eye movements that differed quantifiably across a range of measures when viewing scenes that either did or did not contain a person. We argue that infant's face detection capabilities are ostensibly "better" with naturalistic stimuli and artificial array presentations used in previous studies have underestimated performance.

AbstractThe influence of motor knowledge on speech perception is well established, but the functional role of the motor system is still poorly understood. The present study explores the hypothesis that speech production abilities may help infants discover phonetic categories in the speech stream, in spite of coarticulation effects. To this aim, we examined the influence of babbling abilities on consonant categorization in 6‐ and 9‐month‐old infants. Using an intersensory matching procedure, we investigated the infants' capacity to associate auditory information about a consonant in various vowel contexts with visual information about the same consonant, and to map auditory and visual information onto a common phoneme representation. Moreover, a parental questionnaire evaluated the infants' consonantal repertoire. In a first experiment using /b/–/d/ consonants, we found that infants who displayed babbling abilities and produced the /b/ and/or the /d/ consonants in repetitive sequences were able to correctly perform intersensory matching, while non‐babblers were not. In a second experiment using the /v/–/z/ pair, which is as visually contrasted as the /b/–/d/ pair but which is usually not produced at the tested ages, no significant matching was observed, for any group of infants, babbling or not. These results demonstrate, for the first time, that the emergence of babbling could play a role in the extraction of vowel‐independent representations for consonant place of articulation. They have important implications for speech perception theories, as they highlight the role of sensorimotor interactions in the development of phoneme representations during the first year of life.

AbstractChildren's experiences with differently aged faces changes in the course of development. During infancy, most faces encountered are adult, however as children mature, exposure to child faces becomes more extensive. Does this change in experience influence preference for differently aged faces? The preferences of children for adult vs. child, and adult vs. infant faces were investigated. Caucasian 3‐ to 6‐year‐olds and adults were presented with adult/child and adult/infant face pairs which were either Caucasian or Asian (race consistent within pairs). Younger children (3–4 years) preferred adults over children whereas older children (5–6 years) preferred children over adults. This preference was only detected for Caucasian faces. These data support a 'here and now' model of the development of face age processing from infancy to childhood. In particular, the findings suggest that growing experience with peers influences age preferences and that race impacts on these preferences. In contrast, adults preferred infants and children over adults when the faces were Caucasian or Asian, suggesting an increasing influence of a baby schema, and a decreasing influence of race. The different preferences of younger children, older children, and adults also suggest discontinuity and the possibility of different mechanisms at work during different developmental periods.

AbstractThe 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.

Abstract Human infants, just a few days of age, are known to prefer attractive human faces. We examined whether this preference is human‐specific. Three‐ to 4‐month‐olds preferred attractive over unattractive domestic and wild cat (tiger) faces (Experiments 1 and 3). The preference was not observed when the faces were inverted, suggesting that it did not arise from low‐level image differences (Experiments 2 and 3). In addition, the spontaneous preference for attractive tiger faces influenced performance in a recognition memory task involving attractive versus unattractive tiger face pairings (Experiment 4). The findings suggest that infant preference for attractive faces reflects the activity of general processing mechanisms rather than a specific adaptation to mate choice.

AbstractWe used a novel intermodal association task to examine whether infants associate own‐ and other‐race faces with music of different emotional valences. Three‐ to 9‐month‐olds saw a series of neutral own‐ or other‐race faces paired with happy or sad musical excerpts. Three‐ to 6‐month‐olds did not show any specific association between face race and music. At 9 months, however, infants looked longer at own‐race faces paired with happy music than at own‐race faces paired with sad music. Nine‐month‐olds also looked longer at other‐race faces paired with sad music than at other‐race faces paired with happy music. These results indicate that infants with nearly exclusive own‐race face experience develop associations between face race and music emotional valence in the first year of life. The potential implications of such associations for developing racial biases in early childhood are discussed.

ABSTRACTChildren's social preferences are influenced by the relative status of other individuals, but also by their social identity and the degree to which those individuals are like them. Previous studies have investigated these aspects separately and showed that in some circumstances children prefer high‐status individuals and own‐gender individuals. Gender is a particularly interesting case to study because it is a strong dimension of social identity, but also one of the most prevalent forms of social hierarchy, with males conceptualised as superior to females, by adults and children alike. Here we directly asked how children's social preferences are influenced by status (winner or loser of a zero‐sum conflict) and winner gender (female or male) in different scenarios (same or mixed‐gender). In Experiment 1, children saw same‐gender conflicts between two females or two males and they displayed an overall preference for winners. In Experiment 2, participants watched two mixed‐gender conflicts, one where the female prevailed and one where the male prevailed. In this case, children chose the winner, but only when they had the same gender as themselves. Experiment 3 confirmed that children preferred own‐gender individuals in the absence of conflict or status. Overall, children are sensitive to the relative status of other individuals and use this information to make social decisions. However, preschoolers do not prefer just any individual who wins access to a resource. They preferred dominant individuals, but only when they were of their own gender. This suggests that children's dominance evaluations are modulated by children's social identity.