A group of life scientists at UCLA, and their colleagues, have completed a study that reveals a possible connection between traumatic brain injury (TBI) and post traumatic stress disorder (PTSD). The study was recently published in psychiatric journal Biological Psychiatry. It was financed by the National Institutes of Health, the U.S. Department of Defense, and the UCLA Brain Injury Research Center.
The purpose of the study was to evaluate the connection between traumatic brain injury and PTSD in soldiers returning home from combat. In addition to the potential PTSD link, the study also explains a potential link between traumatic brain injury and an increased incidence of anxiety disorders. The researchers from this study recommend that veterans avoid stressful situations after their return for some time.
The study, which was conducted in a lab by the evaluation of rats, is unfortunately limited. While revealing a correlation, nonetheless the study does not at this time offer an explanation for the correlation. Whether or not the correlation could be incidental, or truly connected, is yet to be determined.
The researchers exposed the rats to both physical and emotional trauma. They kept the traumas separate. Initially, the rats experienced concussive brain trauma. Two days later, the rats were exposed to fear trauma in an environment completely separate from the concussive brain trauma. The researchers found that the rats who had suffered the earlier brain injury demonstrated increased fear than the control group who did not experience the trauma to the brain. The conclusion they came to was that the brain injury made them more susceptible to acquiring an inappropriately intense fear, as if the injury set up the brain to become excessively afraid.
The brain’s region for learning fear is the Amygdala. So to try to understand why the brain seemed to behave in this way, the researchers studied brain tissue from the rats’ Amygdalas. They found that there were an increased number of receptors for excitatory neurotransmitters that enable learning. What that implied to the researchers was that the brain injury leaves the Amygdala in a more excitable state that primes it for developing fear.
This study is potentially an important development for the care of people who have recently experienced traumatic brain injury. As a brain injury lawyer, I often see the effects of anxiety and PTSD in my clients. If, indeed, there is a linkage, and the link can be broken by sheltering brain injury sufferers from being exposed to fear trauma in the weeks following the initial injury, that could be a powerful tool in the arsenal of doctors and brain injury professionals.