How Does Early Brain Organization Promote Language Acquisition in Humans?

Speech processing in adults relies on precise and specialized networks, located primarily in the left hemisphere. Behavioural studies in infants indicate that a considerable amount of language learning already takes place in the first year of life in the domains of phonology, prosody, and word segmentation. Thanks to the progress of neuro-imaging, we can move beyond behavioural methods and examine how the infant’s brain processes verbal stimuli before learning. These studies reveal a structural and functional organization close to what is described in adults and suggest a strong bias for speech processing in these regions that might guide infants in the discovery of the properties of their native language, although no evidence can be provided as yet for speech specificity of such networks.