Disorders of Mood After Traumatic Brain Injury.

Traumatic brain injury (TBI) of any severity can result in broad and persisting biopsychosocial sequelae. Post-TBI sequelae impact, to varying degrees, a person's ability to function at home and work, leading to added emotional distress. It is in the context of these biological, interpersonal, and social disruptions that mood disorders can arise. Mood disorders after TBI occur at a greater frequency than in the general population, with estimates approaching 25% to 50% for major depression, 15% to 30% for dysthymia, and 9% for mania. Post-TBI depression and mania appear to embrace a symptom presentation that is similar to non-TBI depression and mania, and the symptoms can be discerned from other neurobehavioral symptoms. TBI-related brain damage consistently involves regions of the brain that are increasingly recognized as important in the regulation of mood, including the frontal cortex, basal ganglia, and temporal lobes. However, there is insufficient information to postulate a specific neuroanatomic model for post-TBI depression and mania. It is the variable nature of TBI-related brain injury, occurring in the context of other relevant factors that limit the ability to make accurate models to predict who will develop a post-TBI mood disorder.