Association between implicit motor learning and neurological soft signs in schizophrenia

Abstract

IntroductionSchizophrenia (SZ) patients present subtle motor deficits known as Neurological Soft Signs (NSS). Those deficits encompass impairments of motor coordination, sequencing of complex motor acts and sensory integration. It has been shown that SZ patients present also deficits of higher motor functions as implicit motor learning. Growing number of studies indicate that both NSS and implicit motor learning deficits are associated with impairments of common cortico-cerebellar pathways, however relationship between these two deficits has not been evaluated yet.ObjectivesTo assess NSS and implicit motor learning in SZ patients.AimsTo evaluate associations between NSS and implicit motor learning scores in SZ patients.MethodsTwenty schizophrenia patients and 20 healthy controls were examined. Patients were under olanzapine, clozapine or quetiapine treatment. NSS were assessed with Neurological Evaluation Scale (NES). Implicit motor learning were assessed with a use of Serial Reaction Time Task.ResultsSZ patients presented statistically higher NSS scores than healthy controls (P < 0.001) and presented no signs of implicit motor learning. There was statistically significant negative correlation between implicit motor learning score and total score of neurological soft signs (r = −0.44), sequence of motor acts subscore (r = −0.54) and sensory integration subscore (r = −0.47) in SZ patients group (P < 0.05).ConclusionsThere is association between implicit motor learning deficits and neurological soft signs in SZ patients.Disclosure of interestThe authors have not supplied their declaration of competing interest.