This study investigates the relations between two forms of joint action (JA)--movement coordination (MC) and goal attainment--and theory of mind (ToM), contrasting the interactionist and traditional cognitivist views. A custom task was carried out to measure the properties of the JAs between children and their parents, while classical tasks were…

This cross-sectional study explored the relationship between 24-hour movement behaviors and executive function (EF) in preschool children. A total of 426 Han Chinese preschoolers (231 males; 3.8 ± 0.6 years old) from Zhuhai, Guangdong Province, China were selected from October 2021 to December 2021. Accelerometers were used to measure physical…

An inherent component of tool-use actions is the transformation of the user's operating movement into the desired effect. In this study, the relevance of this transformation for young children's learning of tool-use actions was investigated. Sixty-four children at the age of 27-30 months learned to use levers which either simply extended…

The account that word learning starts in earnest during the second year of life, when infants have mastered the disambiguation skills, has recently been challenged by evidence that infants during the first year already know many common words. The preliminary ability to rapidly map and disambiguate linguistic labels was tested in Italian-speaking…

Correlational studies link spatial-test scores and science, technology, engineering, and mathematics achievement. Here we asked whether children's understanding of astronomical phenomena would benefit from a prior intervention targeting a core component of children's projective spatial concepts--understanding that viewers' visual experiences are…

Adults recognize emotions conveyed by bodies with comparable accuracy to facial emotions. However, no prior study has explored infants' perception of body emotions. In Experiment 1, 6.5-month-olds (n = 32) preferred happy over neutral actions of actors with covered faces in upright but not inverted silent videos. In Experiment 2, infants…

Temporal memory in 7-year-olds, 10-year-olds, and young adults (N = 78) was examined introducing a novel eye-movement paradigm. Participants learned object sequences and were tested under three conditions: temporal order, temporal context, and recognition. Age-related improvements in accuracy were found across conditions; accuracy in the temporal…

Longitudinal associations between signaled night awakening and executive functioning (EF) at 8 and 24 months in children with ([greater than or equal to] 3 awakenings, n = 77) and without parent-rated fragmented sleep ([less than or equal to] 1 awakening, n = 69) were studied. EF was assessed with the Switch task at 8 and 24 months. At 24 months,…

The current study examines the developmental trajectory of banging movements and its implications for tool use development. Twenty (6- to 15-month-old) infants wore reflective markers while banging a handled cube; movements were recorded at 240 Hz. Results indicated that through the second half-year, banging movements undergo developmental changes…

Eye movements were recorded while sixty-two 1-year-olds, 4-year-olds, and adults watched television. Of interest was the extent to which viewers looked at the same place at the same time as their peers because high similarity across viewers suggests systematic viewing driven by comprehension processes. Similarity of gaze location increased with…

Age-related increases of speaking rate are not fully understood, but have been attributed to gains in biologic factors and learned skills that support speech production. This study investigated developmental changes in speaking rate and articulatory kinematics of participants aged 4 ("N" = 7), 7 ("N" = 10), 10…

In humans, effortful cognitive processing frequently takes place during social interaction, with eye contact being an important component. This study shows that the effect of eye contact on memory for nonsocial information is different in children with typical development than in children with autism, a disorder of social communication. Direct…

Kinematic measures of children's reaching were found to reflect stable differences in skill level for planning for future actions. Thirty-five toddlers (18-21 months) were engaged in building block towers (precise task) and in placing blocks into an open container (imprecise task). Sixteen children were retested on the same tasks a year later.…

Throughout their 1st year, infants adeptly detect statistical structure in their environment. However, little is known about whether statistical learning is a primary mechanism for event segmentation. This study directly tests whether statistical learning alone is sufficient to segment continuous events. Twenty-eight 7- to 9-month-old infants…

This study examines the development of hammering within an ontogenetic and evolutionary framework using motion-capture technology. Twenty-four right-handed toddlers (19-35 months) wore reflective markers while hammering a peg into a peg-board. The study focuses on the motor characteristics that make tool use uniquely human: wrist involvement,…