[Synchronization between preverbal vocalizations and motor actions in early infancy. I: Pre-canonical babbling vocalizations synchronize with rhythmic body movements before the onset of canonical babbling]

The multimodality of infant's rhythmic movements as a modulator of the interaction with their caregivers

Children's rhythmic movements during the first year of life possess a meaningful predictive validity for later communicative development. However, their role within adult-child interactions is still underexplored. In this study, we examined whether children's rhythmic movements were significantly responded by adults and the role of multimodality and object use in this process. We observed 22 dyads of 9-month-olds and their parents in natural play interactions. Infants' multimodal rhythmic movements increased the probability of adult responding. Adults offered different types of responses and significantly followed the child's focus of attention. These dynamics could support communicative development by promoting joint attention frameworks.

Visible embodiment: gestures as simulated action

Spontaneous gestures that accompany speech are related to both verbal and spatial processes. We argue that gestures emerge from perceptual and motor simulations that underlie embodied language and mental imagery. We first review current thinking about embodied cognition, embodied language, and embodied mental imagery. We then provide evidence that gestures stem from spatial representations and mental images. We then propose the gestures-as-simulated-action framework to explain how gestures might arise from an embodied cognitive system. Finally, we compare this framework with other current models of gesture production, and we briefly outline predictions that derive from the framework.

Relationship between rhythmic behavior and canonical babbling in infant vocal development

The onset of canonical babbling (CB) is a landmark event in infants' vocal development for spoken language. Previous research has suggested that the onset of CB coincides with the peak period of rhythmic activities. To examine this phenomenon in detail, 28 Japanese infants (14 girls, 14 boys) were observed longitudinally from the age of 5 to 9 months. In the experimental sessions, an audible or an inaudible rattle was placed into a hand of each tested infant. Then the number of times that the infant shook the rattle was counted. In the observational sessions, infants' spontaneous rhythmic activities under natural conditions were observed. The result shows that rhythmic activities reached their peak around the onset of CB. When the infants began to babble, they shook whichever rattle was in their hand, regardless of its audibility. After this period, they shook the audible rattles more frequently than the inaudible ones. These findings suggest that, around the onset of CB, infants learn to control their motor activities based on auditory feedback.