Keynote lecture 1
Tuesday, Sep 8, 2015
MPI CBS Hörsaal
Language: a uniquely human trait
Department of Neuropsychology, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany
Language develops as the brain matures. Newborns demonstrate impressive abilities in phonological learning. By the age of 5 months infants are able to learn phonologically coded syntactic non-adjacent dependencies. Although phonologically based learning is present early, it takes a long time before structurally complex sentences can be processed. It will be shown that the maturation of certain brain structures goes together with the development of particular syntactic abilities. In adults the language-related brain regions in the frontal and temporal cortex are connected via several fiber tracts. Ventrally located fiber tracts are taken to support semantic processing. Dorsally there are two tracts: one which connects the temporal cortex to the premotor cortex (PMC) assumed to support auditory-based phonological processes and another tract which connects the temporal cortex to Broca’s area (BA 44), a region known to subserve the processing of syntactic hierarchy. Brain structural data from newborns demonstrate that the ventral connection supporting semantic processes is fully matured at birth, and thus is in place when word learning starts during the first months of life. Of the two dorsal pathways, however, only the pathway to PMC is mature at birth possibly providing the basis for phonologically based learning during early infancy. The pathway to BA 44, however, matures much later. The maturation of this pathway is directly linked to the processing of syntactically complex sentences across development. This indicates that certain milestones in language development can only be achieved once particular brain structures are fully matured.