Fourteen-month-old infants were presented with static images of happy, neutral, and fearful emotional facial expressions in an eye-tracking paradigm. The emotions were expressed by the infant's own parents as well as a male and female stranger (parents of another participating infant). Rather than measuring the duration of gaze in particular areas…

Mental rotation involves transforming a mental image of an object so as to accurately predict how the object would look if it were rotated in space. This study examined mental rotation in male and female 3-month-olds, using the stimuli and paradigm developed by Moore and Johnson (2008). Infants were habituated to a video of a three-dimensional…

A number of studies have investigated infants' abilities to extract and discriminate number from multimodal events. These results have been mixed for several possible reasons, including aspects of the experimental design that provide perceptual cues that are unrelated to number, and are known to influence looking preferences. This experiment used…

Recently, infant researchers have reported sex differences in infants' capacity to map their representation of an occlusion sequence onto a subsequent no-occlusion display. The research reported here sought to identify the extent to which these sex differences are observed in event-mapping tasks and to identify the underlying basis for these…

Reactions to peers' distress were recorded for 52 toddlers (hosts), 18 to 36 months old, who were observed playing with familiar peers in their own homes during 2 sessions, 6 months apart. Four contextual factors were explored: the host's responsibility for the guest's distress, similarity between the toddler and the distressed peer, relative…