Evoked potentials distinguish between nouns and verbs.

Electrocortical correlates of the processing of nouns and verbs were recorded in 32 healthy individuals performing lexical decisions. Analyses of EEG data recorded through 29 channels revealed different topographies of cortical activity evoked by nouns and verbs. Differences were most pronounced at recording sites over the frontal lobes. The stronger motor associations elicited by verbs as measured pre-experimentally seem to be responsible for the topographical differences of event related brain potentials to verbs and nouns. In agreement with recent evidence from brain-damaged subjects, these results provide evidence that (1) nouns and verbs have distinct neural generators and that (2) these generators involve areas outside the classical language regions of the brain.