Neurophysiological preconditions of syntax acquisition.

Although the neural network for language processing in the adult brain is well specified, the neural underpinning of language acquisition is still underdetermined. Here, we define the milestones of syntax acquisition and discuss the possible neurophysiological preconditions thereof. Early language learning seems to be based on the bilateral temporal cortices. Subsequent syntax acquisition apparently primarily recruits a neural network involving the left frontal cortex and the temporal cortex connected by a ventrally located fiber system. The late developing ability to comprehend syntactically complex sentences appears to require a neural network that connects Broca's area to the left posterior temporal cortex via a dorsally located fiber pathway. Thus, acquisition of syntax requires the maturation of fiber bundles connecting the classical language-relevant brain regions.