Transdiagnostic mapping of common and specific regional homogeneity alterations across affective and psychotic...

Major depressive disorder (MDD), bipolar disorder (BD) and schizophrenia (SZ) are generally categorized as distinct diagnoses, but shared clinical, biological and genetic features. Although rich neuroimaging evidence has revealed brain functional alterations in each of these disorders, the transdiagnostic patterns remain poorly understood. A comprehensive literature search was conducted up to March 2025 for resting-state functional MRI studies reporting regional homogeneity (ReHo) abnormalities in MDD, BD or SZ patients, as compared to healthy controls (HC). Voxel-wise meta-analyses of ReHo abnormalities were conducted separately for each disorder using the Seed-based d Mapping toolbox, followed by conjunction and contrast analyses to further identify common and disorder-specific patterns. Our meta-analysis included a total of 90 studies, encompassing 3764 patients (MDD: n = 1703; BD: n = 872; SZ: n = 1189) and 3590 HC. A transdiagnostic pattern of common ReHo increase was identified in the right inferior frontal gyrus, while disorder-specific ReHo alterations were distributed across different large-scale brain networks. Specifically, MDD-specific abnormalities were primarily involved the default mode and subcortical networks; BD-specific abnormalities were mostly identified within the default mode network; SZ patients exhibited more widespread dysfunction spanning across the frontoparietal, and somatomotor networks. These transdiagnostic findings advance the current understanding of neurofunctional mechanisms underlying overlapping and different multi-dimensional features across affective and psychotic disorders, offering novel insights into precision diagnostics and therapeutic targets for individualized psychiatry in the future.