Anxiety and depression are commonly seen after traumatic brain injury, but research into the reasons why is mixed. Some have proposed that anxiety and depression are based on physical injury to the brain, with certain areas being correlated with a higher prevalence of anxiety or depression. Others have stated that unsatisfactory changes in lifestyle after injury contribute to a higher prevalence of psychiatric disorders. Still others suggest that psychiatric disorders that are diagnosed after injury were also present before injury.
A recent study confirmed that people who had anxiety or depression before injury were more likely to also have those disorders after injury. However, the association is not simple. People who did not have a psychiatric disorder before injury were less likely to have one after, but only if they did not also have a limb injury or experience distress in the acute phase of the injury. Those who did experience limb injury or acute injury distress were more likely to experience depression rather than anxiety.
Since research has shown either mixed or complicated results about the issue, the truth about psychiatric disorders after traumatic brain injury probably lies somewhere between all theories.
Gould KR, Ponsford JL, Johnston L, & Schonberger M. Predictive and associated factors of psychiatric disorders after traumatic brain injury: A prospective study. Journal of Neurotrauma. (August 2011).