Dynamic and integrative visual processing abilities in schizophrenia

Visual perceptual functions are frequently disrupted in patients with schizophrenia. The nature and degree of the visual abnormalities experienced by patients provide important information about altered cognitive mechanisms and may serve as potential endophenotypes for classification and diagnosis of schizophrenia.

To characterize dynamic and integrative visual functions and distinguish patients with schizophrenia from healthy controls, we compared performance on six visual tasks between patients and healthy controls. The tasks included binocular rivalry (interocular dynamics), structure from motion (3D-surface dynamics), surround suppression of contrast (contextual modulation), contour integration (form integration), coherent motion (motion integration), and motion speed discrimination (motion sensitivity). The same set of tests was conducted in 61 early-stage outpatients and 69 chronic inpatients and controls, allowing us to see the effects of long-term treatment on patients' visual functions.

Compared with healthy controls, patients experienced slower switching in binocular rivalry but faster switching in structure from motion, along with impaired spatial form integration. Inpatients had reduced motion sensitivity, while outpatients had deficits in motion integration, two groups differed in susceptibility to surround contrast suppression. Multidimensional test data supported more accurate classification between patients and controls.

Patients with schizophrenia have specific patterns of visual perceptual abnormalities in dynamic and integrative information processing, with deficit in coherent motion (considered more state-linked) more apparent in early-stage outpatients and poor motion speed discrimination (linked to stable traits) seen in chronic inpatients. There is a significant advantage of using multiple independent tests to assist in the classification and diagnosis of schizophrenia.