The perinatal brain is well equipped to react to the environment during sleep. Several lines of research in animals and humans prior to and immediately after birth have documented the capability to respond, to process and remember patterns of stimulation. In this article, we will summarize recent findings as well as previous work documenting the memory and learning capacities of the developing brain during sleep and wake states. The role of these sleep state dependent processes may play in the ability to adapt to the postnatal environment will be discussed.

The developmental origins of humans' ability to use objects flexibly as tools remains controversial. Although the dominant approach for conceptualizing tool use development focuses on a qualitative shift in cognition near the end of the first year, we suggest that perception-action theory offers important clues for how infants' earlier exploratory behaviors set the stage for the emergence of tool use. In particular, we consider how infants' attempts to relate objects and surfaces enables them to learn how objects function as extensions of the hand and provide opportunities for practicing the actions that will be recruited for tool use later in development. In this connection, we discuss behavioral and kinematic studies on object manipulation, which show that infants relate objects to surfaces in a discriminative manner and gain greater motor control of banging over the course of the first year. In conclusion, a perception-action perspective suggests that tool use emerges more continuously over developmental time than has traditionally been maintained.

Imagine a child who has never seen or heard language. Would such a child be able to invent a language? Despite what one might guess, the answer is "yes". This chapter describes children who are congenitally deaf and cannot learn the spoken language that surrounds them. In addition, the children have not been exposed to sign language, either by their hearing parents or their oral schools. Nevertheless, the children use their hands to communicate--they gesture--and those gestures take on many of the forms and functions of language (Goldin-Meadow 2003a). The properties of language that we find in these gestures are just those properties that do not need to be handed down from generation to generation, but can be reinvented by a child de novo. They are the resilient properties of language, properties that all children, deaf or hearing, come to language-learning ready to develop. In contrast to these deaf children who are inventing language with their hands, hearing children are learning language from a linguistic model. But they too produce gestures, as do all hearing speakers (Feyereisen and de Lannoy 1991; Goldin-Meadow 2003b; Kendon 1980; McNeill 1992). Indeed, young hearing children often use gesture to communicate before they use words. Interestingly, changes in a child's gestures not only predate but also predict changes in the child's early language, suggesting that gesture may be playing a role in the language-learning process. This chapter begins with a description of the gestures the deaf child produces without speech. These gestures assume the full burden of communication and take on a language-like form--they are language. This phenomenon stands in contrast to the gestures hearing speakers produce with speech. These gestures share the burden of communication with speech and do not take on a language-like form--they are part of language.

From very early in life, expressive behavior is multimodal, with early behavioral coordinations being refined and strengthened over time as they become used for the communication of meaning. Of these communicative coordinations, those that involve gesture and speech have received perhaps the greatest empirical attention, but little is known about the developmental origins of the gesture-speech link. One possibility is that the origins of speech-gesture coordinations lie in hand-mouth linkages that are observed in the everyday sensorimotor activity of very young infants who do not yet use the hand or mouth to communicate meaning. In this article, I review evidence suggesting that the study of gesture-speech links and developmentally prior couplings between the vocal and motor systems in infancy can provide valuable insight into a number of later developments that reflect the cognitive interdependence of gesture and speech. These include aspects of language development and delay, the infant origins of the adult speech-gesture system, and early signs of autism spectrum disorder. Implications of these findings for studying the development of multimodal communication are considered.

L'objectif de cette revue est de présenter une synthèse des réponses que l'on peut actuellement apporter à la question de savoir quelles sont les premières caractéristiques comportementales qui prédisent le développement de l'autisme. L'article se centre sur 5 points : la présence de Troubles du Spectre Autistique (TSA) dans des groupes de frères et sœurs puînés d'enfants déjà diagnostiqués, les patterns et caractéristiques du développement moteur, les patterns et caractéristiques du développement social et émotionnel, les patterns et caractéristiques de la communication intentionnelle verbale et non verbale, et les patterns qui marquent le début de comportements pathognomoniques de TSA. La discussion porte sur les aspects inattendus des résultats et les pistes de recherche nouvelles qu'ils peuvent engendrer.

When individuals reason in an essentialist way about social categories, they assume that group differences reflect inherently different natures (Gelman, 2003; Rothbart & Taylor, 1992). This paper describes the psychological and social implications of essentialist beliefs, and examines the extent to which children exhibit psychological essentialism when reasoning about gender. The authors discuss reasons young children as well as older children show essentialist reasoning in some contexts, but not in others. Finally, the authors suggest directions for future research, and discuss a primary challenge to many working in this field: reduction of rigid gender beliefs.