This research examined how 5-, 8-, and 11-month-olds with female primary caregivers mentally represented faces using a familiarization procedure similar to real-world experience in which infants have greater exposure to female faces aged 21-39 years than other face types. We predicted infants would form weighted representations of faces (i.e.,…

Although action experience has been shown to enhance the development of spatial cognition, the mechanism underlying the effects of action is still unclear. The present research examined the role of visual cues generated during action in promoting infants' mental rotation. We sought to clarify the underlying mechanism by decoupling different…

This research examined whether infants tested longitudinally at 10, 14, and 16 months of age (N = 58) showed evidence of perceptual narrowing based on face gender (better discrimination of female than male faces) and whether changes in caregiving experience longitudinally predicted changes in infants' discrimination of male faces. To test face…

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…

Two studies of 5-month-old infants explored whether a phenomenon reported by K. Wynn (1992) reflects a familiarity preference instead of a mathematical competence. Experiment 1 was a conceptual replication of Wynn's study. When data were analyzed with the relatively liberal statistical approach used by Wynn, the original phenomenon was replicated.…