Neuroleptic treatments and overflow movements in schizophrenia: are they independent?

Neurological soft signs (NSS) are minor neurological abnormalities that can be revealed by a clinical examination focused on sensory and motor information processing. NSS include overflow movements (OMs), which are defined as involuntary movements that may accompany the production of voluntary movements. OM is generally considered to be a characteristic feature of schizophrenia. White matter abnormalities might be involved in the pathogenesis of OMs. Dopamine receptors play a role in oligodendrocytes development. There is a direct link between antipsychotic agents that bind to dopamine receptors on oligodendrocytes and the development of oligodendrocytes and myelin formation. In this paper, we review the current knowledge of the effects of antipsychotic agents on NSS in schizophrenic patients. As a result of this critical review we hypothesize that the neuroleptic actions described in this paper could explain why antipsychotic agents have no effect on the resolution of NSS in patients with schizophrenia.