Visual ERP's will be employed for the following reasons. Auditory P3 attenuation has proven not to change with administration of typical neuroleptics in longitudinal designs (Pfefferbaum et al., 1989). Visual P3, however, may provide a more sensitive measure for detecting changes in illness severity as it is though to be related more to clinical state (Duncan, 1988). The proposed study could possibly reveal improved functioning that has gone undetected in studies employing auditory ERPs. The proposed study would be the first to assess the longitudinal effects of ziprasidone treatment on WM functioning using parametrically altered WM tasks while concurrently obtaining visual ERP's.