Association between implicit motor learning and neurological soft signs in schizophrenia

Abstract

Introduction

Schizophrenia (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.

Objectives

To assess NSS and implicit motor learning in SZ patients.

Aims

To evaluate associations between NSS and implicit motor learning scores in SZ patients.

Methods

Twenty 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.

Results

SZ 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).

Conclusions

There is association between implicit motor learning deficits and neurological soft signs in SZ patients.

Disclosure of interest

The authors have not supplied their declaration of competing interest.