Attenuated late positivity in the visual evoked potential in aphasia induced by lesions in anterior speech area

Seven anterior aphasics, 7 nonbrain-damaged subjects and 7 normal controls were tested for their visual evoked potentials. Aphasics showed an attenuation of the long latency positivity related to interest in the stimulus. The attenuation may indicate the subject's failure to signal communicative intention. Thus the attenuated positivity may be a physiological correlate of a behavioral state (aphasia) induced by brain lesions.