Impairment in visual and spatial perception in schizophrenia and delusional disorder.

The Judgment of Line Orientation Test, a visuospatial processing task, was administered to normal subjects, to schizophrenic patients and to patients with delusional disorder. Significantly better performance was seen in the normal subjects than in the schizophrenic and delusional patients. Delusional patients, in turn, showed better performance than the schizophrenic patients.