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…

It is known that infant-directed speech (IDS) plays a key role in language development. Previous research, however, has also identified significant variability across societies in terms of how often IDS occurs. For example, some studies report very little IDS in non-western, small-scale societies -- including children growing up in small-scale…

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…

This study examined the extent to which the quality of teacher-infant interactions varies across play and routine care activities. In addition, the effects of the quantity of adult involvement in the quality of teacher-infant interactions were investigated. Participants were teachers and infants from 90 infant classrooms in Portugal. Classrooms…

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…

A newborn arrives in this world with the inherent capacity to learn. This includes simple reflexes such as sucking, Moro reflexes, grasping etc. These "pre-installed" capacities help the baby to survive, particularly in the early months before there has been time to gaining new capabilities through learning. Once an infant starts to…

It is known that the rhythms of speech are visible on the face, accurately mirroring changes in the vocal tract. These low-frequency visual temporal movements are tightly correlated with speech output, and both visual speech (e.g., mouth motion) and the acoustic speech amplitude envelope entrain neural oscillations. Low-frequency visual temporal…

Learning to walk allows infants to travel faster and farther and explore more of their environments. In turn, walking may have a cascading effect on infants' communication and subsequent responses from caregivers. We tested for an "inflection point"--a dramatic shift in the developmental progression--in infant communication and caregiver…

Early mother-infant coordinated interactions play a critical role in infant development. The present study describes the development of the dyadic coordination of vocalization and gaze behavior between mothers and infants over the first year of life. In addition to describing developmental trajectories of behavior, the study contributes to our…

What aspects of infants' prelinguistic communication are most valuable for learning to speak, and why? We test whether early vocalizations and gestures drive the transition to word use because, in addition to indicating motoric readiness, they (a) are early instances of intentional communication and (b) elicit verbal responses from caregivers. In…

Fragmented sleep is common in infancy. Although night awakening is known to decrease with age, in some infants night awakening is more persistent and continues into older ages. However, the influence of fragmented sleep on development is poorly known. In the present study, the longitudinal relationship between fragmented sleep and psychomotor…

To understand spoken words, listeners must appropriately interpret co-occurring talker characteristics and speech sound content. This ability was tested in 6- to 14-months-olds by measuring their looking to named food and body part images. In the "new talker" condition (n = 90), pictures were named by an unfamiliar voice; in the…

Introduction: Although recent research has focused on the effects of maternal eating disorders (EDs) on children, little is known about the effect of maternal EDs on neurobiological outcomes in newborns and infants. This study is the first to investigate neurobehavioural regulation and cognitive development in newborns and infants of mothers with…

We investigated longitudinal relations among gaze following and face scanning in infancy and later language development. At 12 months, infants watched videos of a woman describing an object while their passive viewing was measured with an eye-tracker. We examined the relation between infants' face scanning behavior and their tendency to follow the…

To learn motion verbs, infants must be sensitive to the specific event features lexicalized in their language. One event feature important for the acquisition of English motion verbs is the manner of motion. This article examines when and how infants detect manners of motion across variations in the figure's path. Experiment 1 shows that 13- to…