Commentary: Gray Matter Structural Alterations in Social Anxiety Disorder: A Voxel-Based Meta-Analysis.

Abstract

Social anxiety disorder (SAD), an impairing and often chronic psychiatric disorder (1), has a lifetime prevalence between 6 and 13% (2–5) and is prevailing worldwide (6). At present, treatment for SAD is often suboptimal (7–10). Insight in the neurobiological changes underlying the socially-anxious brain is of utmost importance to improve preventive and therapeutic interventions.Until now, several studies have examined alterations in brain structure associated with SAD, by using magnetic resonance imaging (MRI). This method enables investigating changes in gray matter (GM) (11). Results of MRI studies on GM characteristics related to SAD show, however, little consistency and have small effect sizes (12–14).Recently, Wang et al. (15) described a voxel-based meta-analysis on GM volume (GMV) differences between SAD-patients and healthy participants. Such a meta-analytic review is very welcome in order to quantitatively summarize the results of previously published studies and to further increase our understanding of SAD-related GMV alterations. Unfortunately, the paper did not live up to its promise. Wang et al. state that SAD is associated with increased cortical and decreased subcortical GMVs, but these conclusions cannot be deduced from their data. Here, we want to point out several shortcomings that seriously affect this work.