A key region of the brain thought to be involved with emotion is smaller in preschoolers who were previously diagnosed with depression than in their peers who were not depressed, according to research published in November 2014 in JAMA Psychiatry. This part of the brain, called the right anterior insula, may predict the risk of future bouts of depression, reported the research team from the Washington University School of Medicine in St. Louis.
Located on the right and left sides of the brain, the insula is believed to be involved in cognitive function, emotion, perception and self-awareness. Like the children in this study, depressed adults also have smaller insula than peers who are not depressed, research shows. Scientists hope to use MRI scans to better diagnose and treat depression, and to predict who is at risk of recurrent episodes of depression.
This study also found that children diagnosed with so-called “pathological guilt” in preschool also have smaller insula than their peers. This supports previous findings that excessive guilt may be a symptom of depression, but with a twist—related to the size of the insula.