Abnormalities of sentence production in schizophrenia

Abstract

premorbid schizophrenics, and 14 acutely ill psychotic nonschizophrenics. Patterns of reaction time across conditions revealed a perceptual organization dysfunction in 71% of inpatient poor premorbid schizophrenics and 40% of outpatient poor premorbid schizophrenics. This performance pattern was not observed in any good premorbid schizophrenics or psychotic nonschizophrenics. Examination of accuracy rates indicated that all schizophrenic groups demonstrated mild impairments in PO. These data suggest that: !) the sensory register of schizophrenics is performing an adequate segregation of the stimulus field, although to a lesser extent than is the case among psychotic nonschizophrenics; 2) salient configural properties of stimuli do not drive response execution processes for poor premorbid schizophrenics, whereas good premorbid schizophrenics and other psychotic patients are efficient in their use of these cues; 3) poor premorbid schizophrenics' impairment in utilizing relevant cues in response organization is present among remitted patients, but is more prevalent in acutely ill patients. These data support the view that a perceptual organization dysfunction is specific to poor premorbid schizophrenic patients, and that it is most pronounced during acute psychotic episodes. Moreover, the inadequacy of response organization in the context of only mildly impaired target detection is consistent with a frontal lobe origin of this deficit.