Do babies have a sense of agency?

Babies start vocalizing in a goal directed fashion from birth, and to engage in coordinated proto-conversations with their caregivers a few months later, around 3-4-months. Roughly at the same time, they also start using their hands and limbs in a goal-directed fashion. But do babies experience a sense of agency when they perform these actions? Despite the temporal precedence of goal-directed vocal behaviors, research in this domain has mainly focused on audio-visually coordinated limb movements, which has so far led to inconclusive findings (Meyer & Hunnius, 2021; Zaadnoordijk et al., 2020). In this project, we will explore whether a sense of agency over their own vocalisations is already present in 3/4-month-old infants. To this end, we will examine whether infants display sensory attenuation and auditory compensation to genuine or altered vocal feedback during proto-conversations with their caregivers. Research involving adult participants indeed suggests that the functioning of forward models – that can be inferred from sensory attenuation and acoustic compensation - support the sense of agency (Han, Jack, Hughes, Elijah, & Whitford, 2021; Tian & Poeppel, 2015). This project could thus shed a new light on the emergence of the sense of agency during early development.