Bilingual infants acquire languages in a variety of language environments. Some caregivers follow a one-person-one-language approach in an attempt to not "confuse" their child. However, the central assumption that infants can keep track of what language a person speaks has not been tested. In two studies, we tested whether bilingual and…

Word segmentation is a crucial step in children's vocabulary learning. While computational models of word segmentation can capture infants' performance in small-scale artificial tasks, the examination of early word segmentation in naturalistic settings has been limited by the lack of measures that can relate models' performance to developmental…

The purpose of this study is to investigate the relations among children's symbolic functioning at 15 months, joint attention at 24 months, expressive communication at 24 and 36 months, and executive functioning at 36 months. With the sample from rural areas in the United States collected by the Family Life Project (N = 1,008), a longitudinal data…

The purpose of this study was to investigate sub-lexical segmentation in Spanish-speaking children based on the perception of regular syllables (pseudomorphemes), as well as their association with a visual referent. Both of these skills are the precursors to learning morphology for language acquisition. Twenty-three 12-month-old children…

Learning to walk leads to an increase in language abilities; however, the underlying mechanisms accounting for this relation remain unclear. Investigating the quality of early gait control may offer some insights. The purpose of this study was to: (1) quantify how 13-month-olds (n = 39; 39% male) and 24-month-olds (n = 39; 59% male) adapt gait…

Purpose: Though the frequency of gesture use by infants has been related to the development of different language abilities in the initial stages of language acquisition, less is known about whether this frequency (or "gesture rate") continues to correlate with language measures in later stages of language acquisition, or whether the…

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…

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…

Behavioral research has shown that 12- but not 9-month-olds imitate an unusual and inefficient action (turning on a lamp with one's forehead) more when the model's hands are free. Rational-imitation accounts suggest that infants evaluate actions based on the rationality principle, that is, they expect people to choose efficient means to achieve a…

There is currently a hot debate in the literature regarding whether or not infants have a true theory of mind (ToM) understanding. According to the mentalistic view, infants possess the same false belief understanding that older children have but their competence is masked by task demands. On the other hand, others have proposed that preverbal…

Over the last 2 centuries there has been a rapid increase in the proportion of children who grow up in cities. However, relatively little work has explored in detail the physiological and cognitive pathways through which city life may affect early development. To assess this, we observed a cohort of infants growing up in diverse settings across…

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…

Efficient visual exploration in infancy is essential for cognitive and language development. It allows infants to participate in social interactions by attending to faces and learning about objects of interest. Visual scanning of scenes depends on a number of factors, and early differences in efficiency are likely contributing to differences in…

Parent adverse childhood experiences (ACEs) and caregiver reports of harsh parenting were examined in relation to the executive function (EF) abilities in young low-income children. Data were collected from 55 "mother-child" dyads; 17-40 months of age. Parent measures included the ACEs questionnaire and harsh parenting items from the…

Mutual exclusivity (ME) refers to the assumption that there are one-to-one relations between linguistic forms and their meanings. It is used as a word-learning strategy whereby children tend to map novel labels to unfamiliar rather than familiar referents. Previous research has indicated a relation between ME and vocabulary development, which…