From speech perception to vocabulary acquisition in infancy – BABYLANG

During the first year of life, infants become more and more sensitive to the phonological properties of their mother tongue. The present project aims (i) to understand the mechanisms of brain plasticity that underlie the emergence of phonological categories, (ii) to explore the relationship between speech perception and the ability to learn words and concepts, and (iii) to determine early biomarkers of later language development.
My research project aims to determine how the development of the encoding of speech sounds at the cortical and subcortical levels influence the emergence of conceptual representations in humans. To do so, I will evaluate the developmental dynamics of speech sound encoding and novel word learning abilities by longitudinally following full-term and moderate preterm infants during the first two years of their lives. The originality of the project is twofold. On the one hand, the analysis of cortical and subcortical responses in parallel will allow to better understand how the different structures of the auditory pathways communicate with each other in order to optimally encode the spectro-temporal characteristics of speech sounds. On the other hand, the longitudinal following of the same babies from birth until 24 months of age will provide unvaluable infornation about how such early encoding predicts language learning abilities at 2 years of age. In sum, this project will allow deciphering the hierarchy of human language learning mechanisms by bridging the gap between the early stages of speech perception in the first year of life and novel word learning later in life. Ultimately, this project will allow the definition of early predictors of subsequent linguistic deficits often observed in preterm children. The outcomes will have a major societal impact with a direct interest in basic research in cognitive neuroscience, clinical research as well as in the sciences of education.