Background: This resting-state functional magnetic resonance imaging (rs-fMRI) study investigated alterations in voxel-mirrored homotopic connectivity between schizophrenia patients and healthy controls. It further explored the associations between these neural alterations and clinical profiles. The findings aim to enhance the understanding of interhemispheric dysconnectivity in schizophrenia and may offer clues for identifying potential neurobiological substrates of the disorder.
Methods: A total of 38 schizophrenic individuals who attended the psychiatric department were recruited as the experimental group, and 35 healthy volunteers from the medical examination centre were enrolled as the control group during the same time period. Scanning of the subject's entire brain using 3.0T MRI. we finally analysed the correlation between voxel-mirrored homotopic connectivity (VMHC) values and disease severity, disease duration and cognitive function.
Results: (1) VMHC values were significantly lower in the bilateral lingual gyrus in the case group compared to the control group(p<0.05). (2)After applying rigorous False Discovery Rate (FDR) correction for multiple comparisons, the reduction in lingual gyrus VMHC remained specifically and positively correlated with poorer performance in delayed memory (p<0.05,Cohen's d = -1.09). Nominal associations with illness duration and overall symptom severity did not survive this statistical correction. (3) The VMHC values were positively correlated with the total cognitive scale score and the delayed memory factor score (p<0.05, q< 0.015).
Conclusions: This study identifies a robust reduction in interhemispheric functional connectivity within the lingual gyrus of chronic, medicated schizophrenia patients. Critically, the extent of this reduction is specifically linked to the severity of memory impairment, rather than to general symptom profiles. These findings highlight the role of aberrant homotopic connectivity in visual association cortex in the cognitive pathophysiology of schizophrenia and provide a focused neurobiological correlate for future mechanistic and longitudinal investigations.

