Effects of visual remediation on contour integration performance in schizophrenia spectrum disorders

BACKGROUND: Impairments in visual processing, including difficulties in perceptual organization, are well documented in schizophrenia and related serious mental illnesses. These impairments are thought to contribute to reductions in higher-order cognition and functioning. The present study examined whether a visual remediation intervention targeting low- and mid-level visual processing improves perceptual organization in this population. METHODS: Participants with schizophrenia or schizoaffective disorder were randomized to visual remediation (VR) or an active control (AC) condition. The VR intervention targeted contrast sensitivity and contour integration, and perceptual organization was assessed using the Jittered Orientation Visual Integration (JOVI) task. Primary analyses focused on participants who completed the task at baseline, mid-treatment, and post-treatment (N = 50; VR: n = 26; AC: n = 24). Linear mixed-effects models examined JOVI performance as a function of treatment condition, timepoint, and task difficulty (jitter), with planned contrasts testing differential change over time. RESULTS: A significant treatment condition × timepoint interaction indicated that changes in performance differed between groups. Planned difference-in-differences contrasts showed that the VR group exhibited greater improvement from baseline to mid-treatment (estimate = 5.03, p < .001) and from baseline to post-treatment (estimate = 4.30, p = .005) relative to AC. CONCLUSIONS: VR targeting low- and mid-level visual processes improved perceptual organization performance relative to an AC condition in participants with a schizophrenia spectrum disorder. These effects emerged early in training and persisted to the post-treatment assessment, supporting the effectiveness of interventions targeting visual processes for improving perceptual organization in this population.