Neurological soft signs in first-episode psychosis: a systematic review

Abstract

Background: Neurological soft signs (NSS) are minor neurological signs indicating non-specific cerebral dysfunction. Their presence has been documented extensively in schizophrenia but not during the first psychotic episode.

Aims: To review studies that have specifically investigated NSS at the time of the first psychotic episode.

Method: A review of studies investigating neurological function in first-episode psychosis, using a clinical examination.

Results: Patients with first-episode psychosis show an excess of NSS, particularly in the areas of motor coordination and sequencing, sensory integration and in developmental reflexes. Furthermore, NSS may be associated with a specific laterality pattern.

Conclusions: More studies on first-onset schizophrenia are needed, evaluating both sensory and motor neurological domains (scoring separately for the two sides of the body), integrating this knowledge with neuroimaging findings and clarifying the role of NSS as markers of cognitive dysfunction.