Neurological Abnormalities in Schizophrenia and Obsessive-Compulsive Disorder

Myung-Sun Kim; Tae Hyon Ha; Jun Soo Kwon


Curr Opin Psychiatry. 2004;17(3) 

In This Article

Abstract and Introduction

Purpose of Review: Due to the frequent observation of the coexistence of obsessive-compulsive and schizophrenic symptoms in the same patient, there is growing interest in the pathophysiological overlap between the two disorders. In order to identify the similarities and disparities between schizophrenia and obsessive-compulsive disorder, this review summarizes the recent findings from structural/functional neuroimaging, neuropsychological and electrophysiological literature on first-episode schizophrenia and obsessive-compulsive disorder.
Recent Findings: Recent research has identified that structural, cognitive and electrophysiological abnormalities are present in schizophrenia and obsessive-compulsive disorder. In particular, brain abnormalities are present even in the early stage of schizophrenia. The deficits in the frontostriatal and frontotemporal pathways seem to be the pathophysiology of schizophrenia, and frontostriatal deficit is also involved in obsessive-compulsive disorder. Although the frontostriatal deficit is present both in schizophrenia and obsessive-compulsive disorder, schizophrenic patients show more structural abnormalities and cognitive deficits. A few studies directly comparing obsessive-compulsive disorder with schizophrenia have reported interesting findings on the pathophysiological mechanisms of the same neural circuits with functional dissociations.
Summary: Recent research has demonstrated that brain abnormalities are present in first-episode schizophrenia and obsessive-compulsive disorder. There are some pathophysiological similarities, such as deficit of the frontostriatal circuit, between schizophrenia and obsessive-compulsive disorder, but more structural abnormalities are involved in schizophrenia. Future studies, investigating the neurological abnormalities in schizo-obsessive or early-phase psychosis with obsessive-compulsive symptoms, are needed.

Although schizophrenia and obsessive-compulsive disorder (OCD) are separate psychiatric disorders, patients having comorbidity of the two disorders are frequently observed in clinical practice, which has led to the introduction of a new term 'obsessive-compulsive schizophrenia'. Recently, growing interest in the possible overlaps between schizophrenia and OCD have arisen from attempts to explain the pathophysiology of the two disorders on the basis of the functional and structural neuroimaging findings.

Much evidence has been accumulated that suggests abnormalities in brain structure and function are involved in both schizophrenia and OCD. Abnormalities in the frontotemporal and frontostriatal pathways have been considered as pathophysiologies of schizophrenia. The neurological findings in schizophrenia have been criticized for such confounding factors as medication and the chronicity of the illness. In OCD, deficit in the frontostriatal circuit has been consistently implicated as a pathophysiology.

In order to identify the similarities and disparities between schizophrenia and OCD, this review summarizes the findings of the latest studies (November 2002-present) which have investigated brain abnormalities in patients with schizophrenia and OCD. For the structural and functional abnormalities in schizophrenia, only studies that employed first-episode schizophrenia are considered to reduce the effects of confounding factors, such as medication and the chronicity of the illness. The reviewed studies have been grouped into those studying structural/functional, neuropsychological and electrophysiological (event-related potentials) abnormalities in patients with schizophrenia and OCD.


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.
Post as: