Dr. Marjorie Campbell, section chief for prevention and early intervention at the Defense Health Agency's Psychological Health Center of Excellence , says traumatic brain injuries and the psychological effects of experiencing a traumatic event can go hand in hand, but they don't have to.

Campbell, a clinical psychologist at the Silver Spring, Maryland-based PHCoE, has studied the overlap between psychological health and TBI extensively, including being embedded at Naval Hospital Camp Pendleton's Concussion Care Clinic in California. The key, she explained, is figuring out which adverse outcomes can be attributed to TBIs, which can be attributed to conditions like post-traumatic stress disorder, and where there is potential overlap.

"There are three severity levels of TBIs - mild, moderate, and severe," Campbell said. "Over 82% of TBIs in the military are actually considered mild and are better known as concussions."

The severity of a TBI is based on factors including length of loss of consciousness and post-event amnesia, with concussions being at the low end of severity.

Although technically true, referring to concussions as TBIs carries with it an expectation that there is no chance of recovery, which is usually not the case, she explained.

"Within three weeks or so, 90% of individuals sustaining concussions will recover," Campbell said. "Only about 10% go on to develop post-concussion syndrome."

Campbell specializes in studying that 10%.

"When they don't recover, we want to know why," Campbell said. "What's in that group that's continuing to have post-concussive symptoms versus those that get better? I strongly believe it's the psychological health component."

She explained that the possibility likely rests in how that individual sustained the injury. A fall or a sports injury obviously does not carry with it the amount of psychological trauma that an automobile accident or an improvised explosive device explosion during combat does.

"It seems to be that element of trauma that might explain who goes on to develop longer-lasting symptoms," Campbell said.

Symptoms like headaches, sensitivity to light and sound, malaise, fatigue, irritability, depression, anxiety, and dizziness can be associated with a TBI, but are not TBI-specific.

These symptoms are, however, more prevalent in people who have suffered both a concussion and psychological trauma at the same time, Campbell noted.

"What people don’t realize is that there isn’t a strict division between the consequences of experiencing a traumatic brain injury, that seem physically concrete and therefore compelling, and an emotional trauma, which is invisible and might seem 'airy-fairy'," Campbell said.

Watching the World Trade Center fall, being in a motor vehicle accident or experiencing an intense firefight while in combat have the potential to change the brain "without being hit on the head," Campbell explained.

"Trauma alone can change the brain, but when you have the double whammy of a traumatic event and a concussion, determining to which degree psychological aspects versus brain aspects affect them can be difficult to figure out." Campbell said. "We try and do that, and what research has found is that it's the psychological health component that causes these lingering symptoms."

The tendency, she said, is to separate the two, and this does a disservice to everyone, especially the patient.

"The psychological component is probably the bigger burden in terms of outcomes. If you compare someone with post-traumatic stress disorder, or PTSD, and someone with PTSD and a concussion, the person with PTSD and a concussion generally does worse," Campbell said. "But it's counterproductive to over-focus on the concussion when they should have recovered from the acute effects within the first month. If they're not recovering, there's a different reason than the concussion."

Campbell also said that the study of psychological health is integral to the study of TBI and understanding what TBI is.

Her advice to anyone who experiences the short-term impacts of a concussion, whether that be the individual or those around them, is that the symptoms should go away. If they don't, that may be an indicator of another issue.

"The main thing to know is that a bump on the head can distress you and can cause some mild symptoms that should resolve themselves relatively quickly," Campbell said. "In the event that you've had a traumatic event, then you're already compounding the concussion with psychological trauma. If symptoms last longer than four weeks or get worse, the psychological part of it needs to be tended to."

Individuals with lasting symptoms may not necessarily have PTSD, she said, but they're probably experiencing post-concussive symptoms. The bottom line is that a person suffering from the combination of a concussion and a traumatic event usually fares worse.

"People need to know that these two things are related, and they should have someone to talk to," Campbell said.

Looking beyond Campbell's studies, the Psychological Health Center of Excellence is uniquely positioned to collaborate across the Department of Defense, Department of Veterans Affairs, and other agencies to provide leadership and expertise, inform policy and drive improvements in psychological health outcomes.

PHCoE initiatives, such as the Real Warriors Campaign and the inTransition program, address concussions and TBIs in their efforts to help ensure that active-duty and reserve service members, veterans, and retirees have access to both short- and long-term mental health care. PHCoE also collaborates with the Traumatic Brain Injury Center of Excellence to study the overlap of psychological health and TBI conditions.