Post-concussion psychiatric disorders like depression, anxiety and irritability can be extremely disabling for those among the nearly 3.8 million people in the United States who suffer concussions every year. The mechanisms underlying these changes after concussion--also known as mild traumatic brain injury--are not sufficiently understood, and conventional MRI results in most of these patients are normal. Now, a new MRI study has found distinct injury patterns in the brains of people with concussion-related depression and anxiety.