Thesis Jérémie JOSSE

Language is a privileged communicational medium in humans and a key tool for social interaction. To properly adapt to their social world, infants need to learn the words of their native language(s). Interestingly, this learning is far from linear. Infant only start to memorize their first words at around 6-8 months of age. At 12 months, they know the meaning of 10-50 words and start producing some of them. During their second year, this word learning ability improves drastically, leading to a vocabulary of 300-550 words at 24 months of age. While this abrupt improvement or “vocabulary burst” has been widely reported in the literature, the mechanisms underlying this phenomenon remain unclear, and its age of apparition subject to a great inter-individual variability, even in typically-developing (TD) populations. The novelty of this PhD proposal is to posit that developing an attentional control system that optimizes the audiovisual processing of talking faces is a crucial mechanism by which infants learn the words of their native language in live situations. We posit that it triggers their vocabulary burst and boosts infants’ language learning. We argue that this question is fundamental to improve our understanding of the interindividual variability of typical and atypical language development trajectories. We will explore this question combining experimental and modelling approaches, a necessary but still infrequent practice to pinpoint the specific (a)typical mechanisms involved in (a)typical language learning trajectories.

Supervisors :
Olivier PASCALIS olivier.pascalisuniv-grenoble-alpes.fr (olivier[dot]pascalis[at]univ-grenoble-alpes[dot]fr)
Mathilde FORT mathilde.frtgmail.com (mathilde[dot]frt[at]gmail[dot]com) (Co-encadrant)

Mots-clés : word learning,infancy,attention,face,