Motoric neurological soft signs and psychopathological symptoms in schizophrenic psychoses

Motoric neurological soft signs (NSS) were investigated by means of the Brief Motor Scale (BMS) in 82 inpatients with DSM-III-R schizophrenic psychoses. To address potential fluctuations of psychopathological symptoms and extrapyramidal side effects, patients were examined in the subacute state, twice at an interval of 14 days on the average. NSS were significantly correlated with severity of illness, lower social functioning, and negative symptoms. Modest, but significant correlations were found between NSS and extrapyramidal side effects as assessed on the Simpson-Angus Scale. Neither the neuroleptic dose prescribed to the patient, nor scores for tardive dyskinesia and akathisia were significantly correlated with NSS. Moreover, NSS scores did not significantly differ between patients receiving clozapine and conventional neuroleptics. Patients in whom psychopathological symptoms remained stable or improved over the clinical course showed a significant reduction of NSS scores. This finding did not apply to those patients in whom psychopathological symptoms deteriorated. Our findings demonstrate that NSS in schizophrenic psychoses are relatively independent of neuroleptic side effects, but they are associated with the severity and persistence of psychopathological symptoms and with poor social functioning.