By 12 months, English-learning infants have an awareness of the sound patterns of word forms that constitute acceptable labels for objects in their native language. In the following experiments, we replicated and extended previous findings that Canadian English-learning infants will not link function-like words with novel objects. Across three…

Spatial play in early childhood is associated with a variety of spatial and cognitive skills. However, these associations are often derived from studies in which different tasks are used across different age ranges, leaving open the question of how children's natural behaviors during spatial play develop from infancy into the early preschool…

Fourteen-month-olds selectively imitated a sub-efficient means (illuminating a lightbox by a head-touch) when this was modeled by linguistic ingroup members in video-demonstrations. A follow-up study with slightly older infants, however, could replicate this effect only in a video-demonstration context. Hence it still remains unclear whether…

This experiment tests the age at which left-to-right spatial associations found in infancy shift to culture-specific spatial biases in later childhood, for both numerical and non-numerical information. Children ages 1-5 years (N = 320) were tested within an eye-tracking paradigm which required passive viewing of a video portraying a spatial…

Forming social evaluations of others is a core component of social cognition. In this study, the relationship between bilingual experience and social evaluations was investigated in 8-month-old infants. We compared monolingual and bilingual infants' responses to third-party interactions where characters performed prosocial and antisocial actions…

Children's lexical processing speed at 18 to 25 months of age has been linked to concurrent and later language abilities. In the current study, we extend this finding to children aged 36 months. Children (N = 126) participated in a lexical processing task in which they viewed two static images on noun trials (e.g., an ear of corn and a hat), or…

Infants' representations of physical events are surprisingly flexible. Brief exposure to one event can immediately enhance infants' representations of another event. The present experiments tested two potential mechanisms underlying this priming: enhanced encoding or improved retrieval. Five-month-olds saw a target block become hidden inside a…

Being connected to other people at the level of inner and unobservable mental states is one of the most essential aspects of a meaningful life, including psychological well-being and successful cooperation. The foundation for this kind of connectedness is our theory of mind (ToM), that is the ability to understand our own and others' inner…

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…

In human children and adults, familiar face types--typically own-age and own-species faces--are discriminated better than other face types; however, human infants do not appear to exhibit an own-age bias but instead better discriminate adult faces, which they see more often. There are two possible explanations for this pattern: Perceptual…

The development of theory of mind (ToM) in infancy has been mainly documented through studies conducted on a single age group with a single task. Very few studies have examined ToM abilities other than false belief, and very few studies have used a within-subjects design. During 2 testing sessions, infants aged 14 and 18 months old were…

Do young infants understand that pointing gestures allow the pointer to change the information state of a recipient? We used a third-party experimental scenario to examine whether 9- and 11-month-olds understand that a pointer's pointing gesture can inform a recipient about a target object. When the pointer pointed to a target, infants…

We examined whether 14-month-olds learn the mapping between a novel word and object in an associative-learning task when the forms differ minimally in only one segment where the crucial difference occurs in a stressed syllable. Fifty infants were presented with novel word-object pairings. Infants in one group heard the minimal difference in an…

Warning others is a paradigm case of communicative helping and prospective action understanding. The current study addressed the ontogeny of warning in infants' gestural communication. We found that 12- and 18-month-olds ("n" = 84) spontaneously warned an adult by pointing out to her an aversive object hidden in her way…

This study investigates the importance of object function (action-object-outcome relations) on object individuation in infancy. Five experiments examined the ability of 9.5- and 12-month-old infants to individuate simple geometric objects in a manual search design. Experiments 1 through 4 (12-month-olds, N = 128) provided several combinations of…