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…

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…

The present study deals with the influence of specific motor experiences on efficient grasp planning. Forty 5- to 6-year-old children learned to use an unfamiliar tool with either a thumb-up or a thumb-down grip to accomplish a task. Before and after training, the extent to which children would rotate the tool using an awkward initial grip…

Toddlers' understanding of object rotation was investigated using a multimethod approach. Participants were 44 toddlers between 22 and 38 months of age. In an eye-tracking task, they observed a shape that rotated and disappeared briefly behind an occluder. In an object-fitting task, they rotated wooden blocks and fit them through apertures.…

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…

In early childhood, young children frequently engage in object-oriented play. According to cultural-historical activity theory, object-oriented play provides children with opportunities to learn about the characteristics and cultural applications of objects and materials. These characteristics are referred to as rules or affordances of objects and…

Young children sometimes attempt an action on an object, which is inappropriate because of the object size--they make scale errors. Existing theories suggest that scale errors may result from immaturities in children's action planning system, which might be overpowered by increased complexity of object representations or developing teleofunctional…

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…

This report investigates tool learning and its relations to executive functions (EFs) in toddlers. In Study 1 (N = 93), 18-, 20-, 22-, and 24-month-old children learned equally well to choose a correct tool from observation, whereas performance based on feedback improved with age. Knowledge transfer showed significant progress after 22 months of…

This research examined the development of adaptive generalization in infants' object-directed actions. Infants ages 9 and 12 months participated in an object manipulation task with stimulus objects from 2 categories that differed in shape and weight and that bore a consistent shape or weight correspondence. Weight differences between…

This study asked whether children's tendency to imitate selectively (ignore causally unnecessary actions) versus faithfully ("overimitate" causally unnecessary actions) varies across ages and social contexts. In the first experiment, 2-year-olds and 4-year-olds were randomly assigned to play 1 of 3 prior games with a demonstrator: a…

The developing infant learns about the physical and the social world by engaging with objects and with people. In the study reported here, we investigated the relationship between infants' interactions with the physical and the social world. Three-month-old infants were trained for 2 weeks and experienced either actively manipulating objects…

Two studies with 9-, 11- and 13-month-old infants were conducted to investigate infants' ability to use an object's material properties to guide their object-directed actions. In study 1, 9- and 11-month-old infants played in an exploration phase with two objects made of different materials, one very heavy and the other one light and playable.…

This study was designed to examine the cultural sensitivity of the PDMS-2 for Portuguese preschool children aged 36-71 months. A total of 540 children (255 males and 285 females) from 15 public preschools of Viana do Castelo, Portugal, were assessed. Age and gender effects in motor performance were examined. Results indicated that PDMS-2 is valid…

Recent theories on the evolution of language (e.g. Corballis, 2009) emphazise the interest of early manifestations of manual laterality and manual specialization in human infants. In the present study, left- and right-hand movements towards a midline object were observed in 24 infants aged 4 months in a constrained condition, in which the hands…