AUDITORY INFORMATION-PROCESSING IN SCHIZOPHRENIA

Early N1P2 and late N2P3 responses generated in an auditory oddball pa radigm are topographically compared in three psychiatric patient group s. In schizophrenia N-1 and N-2 amplitude is comparable with dementia and significantly decreased with respect to affective disorder. In con trast, P-3 amplitude does not allow discriminating schizophrenia from affective disorder but is significantly diminished in dementia. The la te N2P3 response shows a topographic effect along the fronto-occipital axis. Schizophrenia is characterized by an iCNV and N-2 maximum over the frontal planes and a compound P-3 lacking distinct frontal and par ietal components. The findings are discussed in reference to literatur e data and current hypotheses/theories concerning information processi ng. Our findings favour an important dysfunction of automatic processi ng including early selection in schizophrenia.