TOPOGRAPHIC ABNORMALITIES OF P3 IN SCHIZOTYPAL PERSONALITY-DISORDER

Schizotypy, a schizophrenia spectrum disorder, is of interest because schizotypes share traits with schizophrenics, albeit milder, without p otential confounds such as chronic neuroleptic treatment and/or hospit alization. Thus, schizotypy may be particularly useful in exploring bi ological correlates of an underlying schizophrenic predisposition, The P3 event-related potential, which is aberrant in schizophrenia, was m easured in II male, right-handed, DSM-III-R-defined schizotypes and II matched controls while subjects covertly counted 1.5 kHz target tones (15%) in trains of I kHz standard tones, Like schizophrenics, schizot ypes displayed an asymmetrical P3, with smaller amplitudes over the le ft temporal lobe. Unlike schizophrenics, schizotypes were not signific antly smaller in P3 amplitude over the sagittal midline of the head al though there was a trend towards reduced amplitudes at central and pos terior midline sires, Asymmetry of P3 amplitude, with left-sided defic it, may be associated with the schizophrenia diathesis, but overall P3 reductions may be more associated with chronic effects.