Neuropsychological dysfunction in schizophrenia. Relation to associative thought disorder.
Recent evidence suggests that cerebral atrophy with cognitive deficits is associated with negative schizophrenic symptoms, including poverty of speech and speech content. This report investigates the relationship between specific measures of neuropsychological dysfunction and four major indices of associative thought disorder in schizophrenia, to ascertain whether neuropsychologically impaired schizophrenics show more associative disturbance than neuropsychologically intact schizophrenics. Twenty neuropsychologically intact and 12 impaired schizophrenics, rigorously diagnosed by the Research Diagnostic Criteria, were administered the Luria-Nebraska Neuropsychological Battery. These two groups of schizophrenics were compared on a continuous word-association test, which included two nonverbal and two verbal measures of associative disturbance. The neuropsychologically impaired schizophrenics had slower reaction times (p less than .05), but did not differ from the neuropsychologically intact schizophrenics on the verbal measures. Results indicated a stronger relationship between neuropsychological functions and the nonverbal dimensions (p less than .02), than with the verbal measures. This challenges the assumption that a left hemisphere abnormality in schizophrenia is particularly associated with cognitive disturbance, and suggests that neuropsychologically impaired schizophrenics may show greater potential for negative schizophrenic symptoms.
D000328:Adult; D001244:Association; D004292:Dominance, Cerebral; D005260:Female; D006801:Humans; D008182:Luria-Nebraska Neuropsychological Battery; D008297:Male; D009483:Neuropsychological Tests; D011930:Reaction Time; D012559:Schizophrenia / Q000175:diagnosis*; D012565:Schizophrenic Psychology; D014936:Word Association Tests