Table 1.

Inclusion criteria and exclusion criteria for patients with OCD and controls

Patients with OCD

Inclusion criteria

OCD was diagnosed by two psychiatrists according to the criteria of

DSM-IV

Age ranged from 18 to 50 years

Right handedness

Han Chinese

With the educational level of primary school or higher

First-episode without any anti-OCD drugs or psychotropic drugs

Exclusion criteria

Had a history of serious physical disease, alcohol dependence or drug abuse

Had a history of nervous system disease, such as brain tumor, epilepsy, etc.

Had a history of other mental disorders

With mental retardation

With schizophrenia, affective disorder, and other psychiatric disorders

First degree relatives having mental disorders and/or nervous system disease

Had a contraindication for magnetic resonance inspection

Pregnant or lactating women

Controls

Inclusion criteria

Without OCD and other mental disorders

Age ranged from 18 to 50 years

Right handedness

Han Chinese

With the educational level of primary school or higher

Exclusion criteria

Had a history of serious physical disease, alcohol dependence or drug abuse

Had a history of nervous system disease, such as brain tumor, epilepsy, etc.

Had a history of other mental disorders

First degree relatives having mental disorders and/or nervous system disease

Had a contraindication for magnetic resonance inspection

Pregnant or lactating women

Abbreviations: DSM-IV, Diagnostic and Statistical Manual of Mental Disorders, fourth edition; OCD, obsessive-compulsive disorder.