The connection between brain injuries and depression is widely accepted, although not fully understood. Doctors have long known that some traumatic brain injuries—even concussions—can lead to severe depression and anxiety. But the connection between brain injuries and depression hasn’t been clearly defined. Now, researchers have found a clue: damaged neural signal carriers, deep inside the brain. Studying White Matter in Brain Injury Patients “White matter” —or axons—is the part of the brain cell that passes signals to another cell. White matter is not visible on a conventional MRI. That’s how many traumatic brain injuries (TBI) are diagnosed. A research team at the University of Pittsburgh Medical Center looked at brain scans of patients diagnosed with a mild TBI. Most patients had sustained