Neurological soft signs (NSS) refer to the subtle dysfunctions of motor coordination, sequencing of complex motor acts and sensory integration. NSS are linked with schizophrenia and bipolar disorder, contributing to common biological background of those diseases. Growing number of studies present that both disorders share various functional and structural cerebellar dysfunctions, however schizophrenia and bipolar disorder have not been compared yet in terms of cerebellar motor dysfunctions.

To assess neurological and cerebellar soft signs in schizophrenia and bipolar disorder

To evaluate whether both disorders share similar rate of neurological and cerebellar soft signs

29 patients with schizophrenia, 30 bipolar disorder patients and 24 healthy controls were examined. Patients were under olanzapine, clozapine or quetiapine treatment. In case of BD patients mood stabilizer has been permitted. NSS were assessed with Neurological Evaluation Scale (NES). Cerebellar soft signs were evaluated by International Co-operative Ataxia Rating Scale (ICARS).

Schizophrenia and bipolar disorder patients did not differ significantly in NES and ICARS total scores nor in any of their subscales. Both schizophrenia and bipolar disorder patients presented statistically higher total NES and ICARS scores than healthy controls (p<0.001).

Both schizophrenia and bipolar disorder patients reveal similar motor dysfunctions in terms of neurological and cerebellar soft signs.