Stereopsis deficits in patients with schizophrenia in a Han Chinese population

Although cognitive and sensory deficits have been identified as a core feature of schizophrenia, only a small portion of visual sensorium has been explored. To date, studies on visual system of three-dimensional percepts based on two-dimensional information still are limited. This study is the first to examine the integrity of stereopsis of schizophrenia in a Han Chinese population, and to further investigate the correlation of stereopsis with clinical symptoms. 100 patients with schizophrenia and 80 healthy controls were recruited. We assessed stereoacuity using the Titmus Stereopsis Test and clinical symptoms using Chinese versions of the Scales for the Assessment of Positive and Negative Symptoms (SAPS and SANS). There was a significant difference in log seconds of arc between two groups (p < 0.0001). The percentage of patients with correct stereopsis detection was significantly reduced at 400, 200, 140, 100, 80, 60, 50, and 40 seconds of arc than healthy controls (all, p < 0.01). Log seconds of arc in patients was not correlated with total scores and subscores of SAPS and SANS (all, p > 0.05). Our findings support that patients with schizophrenia have a marked deficit of stereopsis in a Han Chinese population. However, clinical symptoms do not influence stereopsis of schizophrenia.