When geometric and non-geometric information are both available for specifying location, men have been shown to rely more heavily on geometry compared to women. To shed insight on the nature and developmental origins of this sex difference, we examined how 18- to 24-month-olds represented the geometry of a surrounding (rectangular) space when…

Three experiments investigated the effect of an adult's social cues on 2- and 3-year-old children's ability to use a sign or symbol to locate a hidden object. Results showed that an adult's positive, engaging facial expression facilitated children's ability to identify the correct referent, particularly for 3-year-olds. A neutral facial expression…

In two experiments on very young children's response to the orientation of pictures and objects, 18-, 24- and 30-month-old children showed no preference for upright pictures over inverted ones. More importantly, we found that children in all three age groups were equally accurate and equally fast at identifying depicted objects regardless of…

Chimpanzees ("Pan troglodytes") and bonobos ("Pan paniscus") (Study 1) and 18- and 24-month-old human children (Study 2) participated in a novel communicative task. A human experimenter (E) hid food or a toy in one of two opaque containers before gesturing towards the reward's location in one of two ways. In the Informing condition, she attempted…

Research over the past 20 years has revealed that even very young infants possess expectations about physical events, and that these expectations undergo significant developments during the first year of life. In this article, I first review some of this research, focusing on infants' expectations about occlusion, containment, and covering events,…

Previous research has shown that young children have difficulty searching for a hidden object whose location depends on the position of a partly visible physical barrier. Across four experiments, we tested whether children's search errors are affected by two variables that influence adults' object-directed attention: object boundaries and…

While very young children's understanding of objects as symbols for other entities has been the focus of much investigation, very little is known concerning the emergence of comprehension for symbolic relations among actions modeled with toy replicas and their real counterparts. We used videotaped depictions of real actions in a preferential…

Infants follow the gaze direction of others from the middle of the first year of life. In attempting to determine how infants understand the looking behavior of adults, a number of recent studies have blocked the adult's line of sight in some way (e.g. with a blindfold or with a barrier). In contrast, in the current studies an adult looked behind…