How Post-traumatic Stress Disorder Works

Thirteen years after he returned home to Las Vegas, Nev., from fighting in Iraq, Adam Kelley, a specialist in the U.S. Army, took his own life. While fighting in the Persian Gulf during the first Iraq War, he watched as one of his friends died. He saw the killing of countless soldiers on both sides. He killed others with the mortar rounds he fired. He was under heavy fire for days at a time. After he returned home, he relived the terrifying events through nightmares and flashbacks. Ultimately, although he was treated with medications, he was unable to shake his demons. Kelley shot himself [source: Las Vegas Review Journal].

What Kelley endured for 13 years is what researchers now refer to as post-traumatic stress disorder (PTSD).

Previously called shell shock, it was first described by a doctor during the Civil War and was first noticed on a massive scale during World War I. The first diagnosis of the modern view of PTSD came in 1980. Research into this anxiety disorder began intensely after Congress requested a study of how Vietnam veterans were adjusting back to civilian life in 1983. The National Vietnam Veterans' Readjustment Study turned up a wealth of statistics and provided rare insight on a large scale into the nature of PTSD.

But there's still much to learn. For instance, there's no comprehensive data on the number of PTSD sufferers who, like Adam Kelley, commit suicide. And there's debate over how many soldiers fighting in the second Iraq War are vulnerable to developing the disorder later on. Also, many health-care professionals are still exploring the best type of counseling and medication to most effectively treat PTSD.

But the findings from the Vietnam study helped to advance human understanding of the effects of PTSD by leaps and bounds. We now know, for example, that the part of the brain that stores memories of fearful incidents can be directly related to the development of the disorder. We also now know that some people are more prone to develop PTSD after experiencing a trauma than others. And the duration, intensity and danger of a traumatic experience are known to be directly related to the development of PTSD.

It's also clear to researchers that PTSD can also develop in people who have never set foot on a battlefield. The disorder can be found in civilians, men, women and children. It can also result from a number of different traumatic experiences -- not just one.

It's this expanded understanding of PTSD that will eventually allow psychologists to properly treat the disorder and also help clinicians to create drugs that not only alleviate the symptoms of the disorder, but also the mental processes behind them. The military is even exploring the possibility of developing an "inoculation" against PTSD (more on that later).

But in many ways the disorder is still a mysterious one, and its sufferers are often misunderstood. In this article, we'll examine this disorder and the effects it has on the lives of people who suffer from it.­