How do age and the acquisition of independent walking relate to changes in infants' everyday experiences? We used a novel ecological momentary assessment (EMA) method to gather caregiver reports of infants' restraint, body position, and object holding via text messages sparsely sampled across multiple days of home life at 10, 11, 12, and 13 months…

Repetition is a salient strategy used by human and non-human cohorts for learning and controlling behavior. It this research project, a case study was conducted to explore deliberate voluntary repetition in younger cohorts during their spontaneous solitary play with single or multiple objects. Two main types of repetition -- blocked and random --…

The current study is the first to examine the role of exploration in play milestones development using a multi-measure micro-analytic approach. Fifteen infants, between the ages of 8 and 17 months, were observed in their natural home environment once a month for a one--hour session; their spontaneous mouthing and fingering and their play level…

Object play yields enormous benefits for infant development. However, little is known about natural play at home where most object interactions occur. We conducted frame-by-frame video analyses of spontaneous activity in two 2-h home visits with 13-month-old crawling infants and 13-, 18-, and 23-month-old walking infants (N = 40; 21 boys; 75%…

Early object name learning is often conceptualized as a problem of mapping heard names to referents. However, infants do not hear object names as discrete events but rather in extended interactions organized around goal-directed actions on objects. The present study examined the statistical structure of the "nonlinguistic" events that…

Previous research yielded conflicting reports as to whether infants grasped at both depicted and real objects, which led to questions about the nature of their conceptual understanding of objects represented in pictures. This study set out to further clarify whether infants actually grasp at pictured objects compared to real objects and other flat…

Infants build knowledge by acting on the world. We conducted an ecologically grounded test of an embodied learning hypothesis: that infants' active engagement with objects in the home environment elicits caregiver naming and cascades to learning object names. Our home-based study extends laboratory-based theories to identify real-world processes…

Fifty-one 23-to-55-month-old-infants faced two apparatuses that required the use of a rigid (box apparatus) or flexible (hose apparatus) stick-like tool to retrieve a toy stuck inside. Before attempting the extraction, however, they had to pick the only one tool (of three) on display that had the appropriate rigidity/flexibility to be effective.…

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…

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…

Manual skills slowly develop throughout infancy and have been shown to create clear views of objects that provide better support for visually sustained attention, recognition, memory, and learning. These clear views may coincide with the development of manual skills, or that social scaffolding supports clear viewing experiences like those…

Previous papers in these pages have dealt empirically with the child's first words, the child's first imitations, and the use of yes/no and wh-questions with infants. In this study, we touch on all these issues, but attempt to place them in a systemic-functional language framework and a cultural-historical learning one. First, we deal with some of…

Purpose: Infants with autism spectrum disorder (ASD) produce fewer play actions and gestures than neurotypical infants (e.g., Mastrogiuseppe et al., 2015; Veness et al., 2012; Zwaigenbaum et al., 2005). The purpose of this study was to investigate whether different "types" of actions and gestures are more or less likely to develop…

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…

Seven- to 12-month-olds were trained to press levers that contingently activated lights. Infants had the choice of turning on either a light an adult interaction partner was looking at or a light that she turned away from. By 9 months, infants reliably turned on the light that the adult was looking at. In a second study, 9- and 12-month-old…