By analyzing certain aspects of daily brain function, doctors can potentially identify those individuals most likely to develop PTSD, anxiety disorders or depression in the aftermath of traumatic experiences, according to new research from two American universities.
A significant minority of people who live through highly traumatic events or situations will develop serious mental health issues in the aftermath of their trauma exposure. In a study published in February 2015 in the journal Neuron, researchers from Duke University and the University of North Carolina at Chapel Hill explored the possibility of using activity levels inside a brain structure called the amygdala to help predict who will develop mental health problems after living through trauma.
Trauma Exposure and Mental Health
In the context of mental health, doctors and researchers use the term trauma to identify events or situations capable of overriding the natural human ability to adjust to changing circumstances and maintain a sense of psychological/emotional well-being. Some forms of trauma have a physical component while others do not. In either case, the main factor is the emotional/psychological reaction to life-changing or life-threatening experiences. Known possible sources of trauma include physical or sexual assault, physical abuse in childhood, sexual abuse in childhood, direct or indirect exposure to combat situations, direct or indirect exposure to terrorism, exposure to a natural disaster, involvement in a major accident and exposure to serious or severe illness.
Post-traumatic stress disorder (PTSD) is perhaps the most well-known mental health condition associated with living through highly traumatic experiences. Men who live through such experiences have about an 8 percent chance of developing PTSD, while women who live through such experiences have a roughly 20 percent chance of the developing the disorder. Other mental health conditions linked to trauma exposure include major depression and other forms of depressive illness, as well as substance use disorders and several conditions classified as anxiety disorders (e.g., panic disorder, social anxiety disorder and generalized anxiety disorder). These conditions may appear in combination with PTSD or on their own. When combined with PTSD, they can have a particularly damaging impact on health and well-being.
The amygdala is the common name for a functionally identical pair of structures located in either side of the human brain. Humans rely on these two structures to perform such critical tasks as processing strong emotions, connecting emotional reactions to their appropriate context and knowing when to transition from one emotional state to another. The amygdala also helps initiate key survival-oriented reactions, such as eating food when you’re hungry and deciding whether to face dangerous situations or escape to safety.
Can Doctors Predict Trauma Reactions?
In the study published in Neuron, the Duke University and University of North Carolina researchers used data gathered from several hundred young adults enrolled in college to determine if the activity level inside the brain’s amygdala can help doctors predict who will develop PTSD, anxiety, depression or other mental health issues in the aftermath of exposure to emotional trauma. Most of the participants had not gone through the extreme types of trauma exposure usually linked to the development of mental health problems. Instead, they had experienced more common forms of trauma, such as the death of a loved one or loss of a job.
In the first phase of the study, the researchers exposed the participants to threatening images designed to provoke an increase of activity inside the amygdala. Over the next several years, they asked all of the participants to complete a questionnaire and online survey four times annually. The questionnaire was designed to detect symptoms of anxiety and depression, while the survey asked each participant to detail his or her recent exposure to emotionally traumatic circumstances, as well as his or her reaction to this exposure. Some of the participants stayed involved in the project for four full years.
After analyzing all of the collected data, the researchers concluded that the participants who exhibited the highest levels of amygdala activity in the initial phase of the study had a tendency to experience relatively severe symptoms of anxiety and depression in the aftermath of later traumatic or stressful experiences. In line with this finding, they also concluded that it may be possible to use tests of amygdala activity to help identify those individuals who have the highest chances of developing damaging trauma reactions in future years.