Language network

The language network is the predominantly left-lateralised perisylvian system that supports the production and comprehension of spoken and written language. Its classical anterior hub is Broca’s area in the inferior frontal gyrus, and its posterior hub is Wernicke’s area in the posterior superior temporal region, with the angular and supramarginal gyri contributing to lexical and phonological processing.

These hubs are linked by long association tracts, principally the arcuate fasciculus and the superior longitudinal fasciculus, whose disruption produces conduction aphasia. The uncinate fasciculus contributes to the anterior temporal semantic system.

Lesion studies anchor the clinical taxonomy of the aphasias: anterior lesions tend to impair fluent production while sparing comprehension, and posterior lesions tend to impair comprehension while leaving fluent but error-prone output.