Does knowledge of other people's minds grow from concrete experience to abstract concepts? Cognitive scientists have hypothesized that infants' first-person experience, acting on their own goals, leads them to understand others' actions and goals. Indeed, classic developmental research suggests that before infants reach for objects, they do not…

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%…

Background: Spontaneous upper extremity movements in infancy provide insight on neuromotor development. Spatiotemporal kinematics have been used to evaluate typical development of reaching, a foundational motor skill in infancy. This study evaluates the relationship between spontaneous upper extremity movements, not elicited by a toy, and motor…

Research has documented elevated experiences of racial discrimination among African American families, and its adverse impacts on their psychological well-being. However, most studies have investigated the experiences of and consequences for older children and adults. The goal of the current study was to examine the relations among mothers'…

Infancy is a period of significant change for both the brain and behavior. During the first two years of life, the brain experiences an explosion of synaptic connections and myelination, alongside rapid development in motor, linguistic, and social behavioral abilities. Understanding the relationship between brain development and behavioral…

Dance is a universal human behavior and a crucial component of human musicality. When and how does the motivation and tendency to move to music develop? How does this behavior change as a process of maturation and learning? We characterize infants' earliest dance behavior, leveraging parents' extensive at-home observations of their children.…

Over the past 50 years, scientists have made amazing discoveries about the origins of human language acquisition. Central to this field of study is the process by which infants' perceptual sensitivities gradually align with native language structure, known as "perceptual narrowing." Perceptual narrowing offers a theoretical account of…

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…

Children raised in chaotic households show affect dysregulation during later childhood. To understand why, we took day-long home recordings using microphones and autonomic monitors from 74 12-month-old infant-caregiver dyads (40% male, 60% white, data collected between 2018 and 2021). Caregivers in low-Confusion Hubbub And Order Scale (chaos)…

Communication is commonly viewed as connecting people through conscious symbolic processes. Infants have an immature communication toolbox, raising the question of how they form a sense of connectedness. In this article, we propose a framework for infants' communication, emphasizing the subtle unconscious behaviors and autonomic contingent signals…

Developmental psychology focuses on how psychological constructs change with age. In cognitive development research, however, the specifics of this emergence is often underspecified. Researchers often provisionally assume linear growth by including chronological age as a predictor in regression models. In this work, we aim to evaluate this…

Pacifier use during childhood has been hypothesized to interfere with language processing, but, to date, there is limited evidence revealing detrimental effects of prolonged pacifier use on infant vocabulary learning. In the present study, parents of 12- and 24-month-old infants were recruited in Oslo (Norway). The sample included 1187 monolingual…

Since birth, infants develop the ability to perceive a wide range of intersensory relations among various kinds of amodal temporal information. This study addresses the development of the ability to perceive duration-based intersensory relations. Three groups of infants, four, seven and 10 months old, participated in two trials of an intersensory…

The current study explored the link between mouthing and fingering and vocal behaviours directed to objects and caregivers. Nine infants were tracked from the ages of 8-16 months by video recording their mouthing and fingering vignettes and vocal behaviours and vocal behaviours resulting in a total of 2,061 coded behaviours. Microanalysis revealed…

This study quantified the spatial exploration of 13 infants born very and extremely preterm (PT) at 4 months corrected age as they learned that moving their feet vertically to cross a virtual threshold activated an infant kick-activated mobile and compared results to 15 infants born full-term (FT) from a previously published study. Spatial…