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…

Providing equitable informal science, technology, engineering, and mathematics (STEM) learning opportunities to young children from diverse backgrounds may be a way to increase access and interest in STEM and can help to address the broader goal of increasing representation. Importantly, these learning experiences must be meaningful and engage…

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.…

Past research has shown that children's mental rotation skills are malleable and can be improved through action experience--physically rotating objects--or gesture experience--showing how objects could rotate (e.g., Frick, Ferrara, & Newcombe, 2013; Goldin-Meadow et al., 2012; Levine, Goldin-Meadow, Carlson, & Hemani-Lopez, 2018). These…

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…

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 experiment examined how multiple planning constraints affect grasp posture planning in 6- to 10-year-old children (n = 16 in each group) by manipulating the intended object end-orientation (left end-down, right end-down) and initial precision demands (standard, initial precision) of a bar transport task. Results indicated that grasp posture…

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…

A hierarchical progression in infants' ability to use surface features, such as color, as a basis for object individuation in the first year has been well established (Tremoulet, Leslie, & Hall, 2000; Wilcox, 1999). There is evidence, however, that infants' sensitivity to surface features can be increased through multisensory (i.e.,…

Two experiments examined the flexibility and stability with which children and adults organize locations into categories on the basis of object relatedness. Seven-, 9-, and 11-year-olds and adults learned the locations of 20 objects belonging to 4 categories. Displacement patterns revealed that children and adults used object cues to organize the…

The authors examined 14- to 26-month-old infants' understanding of the spatial relationships between objects and apertures in an object manipulation task. The task was to insert objects with various cross-sections (circular, square, rectangular, ellipsoid, and triangular) into fitting apertures. A successful solution required the infant to…