In a study analyzing whole-brain images from nearly 16,000 people, researchers at the Stanford University School of Medicine identified a common pattern across a spectrum of psychiatric disorders that are widely perceived to be quite distinct. The meta-analysis of 193 peer-reviewed papers, published Feb. 4 in JAMA Psychiatry, reports a loss of gray matter in three brain structures that, although physically separate, participate in a network associated with high-level functions, including planning and decision-making. The findings call into question a longstanding tendency to distinguish psychiatric disorders chiefly by their symptoms rather than their underlying brain pathology. To address that question, he and his colleagues pooled data from 193 separate studies containing, in all, magnetic-resonance images of the brains of 7,381 patients falling into six diagnostic categories: schizophrenia, bipolar disorder, major depression, addiction, obsessive-compulsive disorder and a cluster of related anxiety disorders. Comparing the images with those from 8,511 healthy control subjects, the research team identified three separate brain structures, several centimeters apart from one another, with a diminished volume of gray matter, the brain tissue that serves to process information. These structures -- the left and right anterior insula and the dorsal anterior cingulate -- are known to be parts of a larger network in the brain whose component parts tend to fire in synchrony. This network is associated with higher-level executive functions such as concentrating in the face of distractions, multitasking or task-switching, planning and decision-making, and inhibition of counterproductive impulses. Gray matter loss in the three brain structures was similar across patients with different psychiatric conditions, the researchers found.