1. The reproducibility of grey matter volume differences in psychiatric disorders

COEX 

Voxel-based morphometry (VBM) [1] has been used extensively to study anatomical differences between people with psychiatric illness and healthy controls. However, the results of these studies have often been difficult to replicate [2]–[6], which may be driven in part by the well-known clinical heterogeneity within psychiatric disorders. Despite this heterogeneity, a fundamental assumption in psychiatric neuroimaging is that each disorder is associated with some core neural phenotype that should be replicable and consistent across different samples and study locations. If such a consistent phenotype cannot be identified, there may be questionable value in ongoing attempts to examine group differences in small, individual studies. Here, we investigated the degree to which five psychiatric disorders––Autism Spectrum Disorder (ASD), Bipolar Disorder (BD), Mood Disorder (MDD), Schizoaffective (SCA), and Schizophrenia (SCZ)––show consistent neuroanatomical phenotypes by examining correlations between disorder- and site-specific maps of grey matter volume alterations.