Short Summary/Abstract:

The Enhancing Neuroimaging Genetics through Meta-Analysis (ENIGMA) consortium has successfully identified structural brain abnormalities in individuals at Clinical High Risk for Psychosis (CHR) and Schizophrenia (SCZ) using the FreeSurfer pipeline. However, FreeSurfer's parcellation-based approach may miss subtle, spatially distributed differences in brain morphology. This study aims to complement prior ENIGMA findings by applying voxel-based morphometry (VBM), a technique that examines gray and white matter differences on a voxel-by-voxel basis, to identify alterations that FreeSurfer potentially does not capture. Using structural MRI data from the Psy-ShareD project, we will investigate voxel-wise differences in gray and white matter volume between clinical individuals (i.e., individuals with CHR and SCZ and additionally first-episode psychosis, FEP) and healthy controls (HC). Additionally, we will explore associations between gray or white matter volume and clinical symptoms scales (PANSS and CAARMS), antipsychotic use, and IQ. Data will be analyzed using the ENIGMA VBM tool, with a voxel-wise meta-analysis framework (primary plan) and a mega-analysis framework (secondary plan). This study will provide a more detailed characterization of structural brain alterations in these clinical populations and may help identify neuroanatomical markers predictive of psychosis onset.