Wild Chimpanzees Show a Decrease in Pant Grunting over Their First 6 Years of Life.

Data from a large cross-sectional sample of wild chimpanzee mother-infant dyads yield evidence that young chimpanzees' pant grunting unfolds nonlinearly over the early developmental period. Though infants begin pant grunting early, and mothers' rates did not decrease, infant pant grunting declined as infants aged through infancy. Mother-infant dyadic pant grunting discordance therefore increased over infancy, with some discordance observed at even the earliest ages. In half of 90 observed instances involving infants ranging in age from 2 weeks to 69 months, only one member of the mother-infant dyad pant grunted; infants' pant grunting was not influenced by their mother's age, their position on their mother's body at the time of the greeting, or the dominance status of the male greeted. Male infants were more likely to pant grunt than female infants. We discuss the developmental trend in the context of infants' increasing independence, changing social motivations, and male-dominated social hierarchy.

Initial investigations into preschoolers' mirror-style versus transposed bodily imitation.

In typical development, imitation plays a key role in sociocognitive competence. The current study investigated a hypothesised developmental trajectory in face-to-face full body imitation style in 91 preschoolers, as well as a relation between imitation style and theory of mind (ToM). Children's response style to 8 lateralized action prompts was recorded as either "mirror" or "transposed." Overall, mirror-style response increased with age, and was predominant for children and an adult comparison group. Imitation style varied depending on the prompt given, with certain actions showing a side bias regardless of prompt viewed. Mirror-style response was correlated with ToM performance after controlling for language ability, but not after controlling for age. Findings are discussed regarding the hypothesised relation between postural synchrony and larger perspective-taking competence.

The Social Context of Infant Intention Understanding.

Traditional looking-time paradigms are often used to assess infants' attention to socio-cognitive phenomena, but the link between these laboratory scenarios and real-world interactions is unclear. The current study investigated hypothesized relations between traditional social-cognitive looking-time paradigms and their real-world counterparts in caregiver-infant social interaction. Seventy-five 10- to 12-month-old infants participated in a structured play session with their caregiver, as well as a traditional looking-time paradigm targeting intentional action. Infants' ability to quickly parse intentional displays correlated with several key qualities of their everyday interactions. In particular, caregiver and infant interaction quality, maternal supportiveness, caregiver and infant joint engagement skill, and social attentiveness in infants correlated with faster habituation to looking-time displays. These results support a linkage between social-cognitive looking-time laboratory paradigms and more naturalistic partner interaction, at this key age. The data both provide external validation for the large body of social-cognitive findings emerging from laboratory looking-time paradigms, and contribute to a growing literature tracking the developmental trajectory of infants' understanding of people over the first two years.

Delayed Self Recognition in Autism: A Unique Difficulty?

Achieving a sense of self is a crucial task of ordinary development. With which aspects of self do children with autism have particular difficulty? Two prior studies concluded that children with autism are unimpaired in delayed self-recognition; we confirm and clarify this conclusion by examining it in conjunction with another key aspect of self understanding, including several needed controls and contrasts. Three groups of children were tested in a delayed self-recognition paradigm as well as a self-other action memory card game in which they took turns placing pictures with an adult: 3-year-olds (n = 25), 5-year-olds (n = 27), and children with autism spectrum disorder (n = 20). Children with autism spectrum disorder (ASD) demonstrated impaired performance on self-other recall compared to both typical 5-year-olds and typical 3-year-olds, but were not significantly different on delayed self-recognition. Results are discussed with regard to the unique profile of self-related performance in autism.

Infant social attention predicts preschool social cognition.

Recent research examining infants' understanding of intentional action claims to be studying the early origins or precursors of children's later theories of mind If these infant understandings are continuous with later preschool achievements, there should be empirical connections between the two. We provide initial evidence that infants' social attention predicts later social cognition. Specifically, 14-month-olds' habituation to human intentional action significantly predicts later preschool mentalistic construal of persons, as measured on a Theory of Mind Scale.

Psychological diversity in chimpanzees and humans: new longitudinal assessments of chimpanzees' understanding of attention.

We present the results of 5 experiments that assessed 7 chimpanzees' understanding of the visual experiences of others. The research was conducted when the animals were adolescents (7-8 years of age) and adults (12 years of age). The experiments examined their ability to recognize the equivalence between visual and tactile modes of gaining the attention of others (Exp. 1), their understanding that the vision of others can be impeded by opaque barriers (Exps. 2 and 5), and their ability to distinguish between postural cues which are and are not specifically relevant to visual attention (Exps. 3 and 4). The results suggest that although chimpanzees are excellent at exploiting the observable contingencies that exist between the facial and bodily postures of other agents on the one hand, and events in the world on the other, these animals may not construe others as possessing psychological states related to 'seeing' or 'attention.' Humans and chimpanzees share homologous suites of psychological systems that detect and process information about both the static and dynamic aspects of social life, but humans alone may possess systems which interpret behavior in terms of abstract, unobservable mental states such as seeing and attention.