The clinical correlates of neurological soft signs in chronic schizophrenia.

Among 16 chronic schizophrenic in-patients, all had at least one neurological soft sign (NSS), and 6 (40%) had definite neurodysfunction. NSS and TD scores were highly intercorrelated, and NSS were significantly correlated with neuroleptic drug exposure. NSS correlated positively with both positive and negative symptoms and cognitive impairment but not with cerebral ventricular size on CT. Patients with neurodysfunction had more positive and negative psychopathology, cognitive impairment and TD than those without. Cerebral ventricular sizes and family histories of schizophrenia were similar in both NSS groups. The presence of NSS may be a simple but important way of identifying a subgroup of schizophrenics with neurodevelopmental predisposing abnormalities, and vulnerability to TD.