
Post-Traumatic Stress Disorder
(PTSD), mental disorder that follows an occurrence of extreme
psychological stress, such as that encountered in war or resulting from
violence, childhood abuse, sexual abuse, or serious accident. The
stressful event is usually followed by a period of emotional numbness
and denial that can last for months or years. After that period,
symptoms such as recurring nightmares, "flashbacks, short-term
memory problems, insomnia, or heightened sensitivity to sudden noises
may begin. In some cases outbursts of violent behavior have been
observed. The usual treatment for PTSD is individual psychotherapy,
including anxiety management, or group psychotherapy with others who
have the disorder. Some anti-anxiety and antidepressant drugs are being
studied for their effectiveness.
Certain traits (a history of depression, shyness, impulsivity) appear
to heighten a person's risk of experiencing PTSD after a traumatic
event. In those who do experience it, there is growing evidence that
actual physical changes occur in the brain. The hippocampus, a structure
that lies deep in the brain and that is associated with memory, has been
found to be smaller in PTSD victims. It has been hypothesized that
excesses of cortisol, a steroid hormone released during periods of
extreme stress, may damage nerve fibers in the area or actually kill the
nerve cells. However, the role of cortisol is not completely understood;
studies of concentration camp survivors found abnormally low levels of
cortisol rather than abnormally high levels.
Post-traumatic stress disorder was referred to as "shell shock
after World War I and as "battle fatigue after World War II and was
traditionally thought of as a condition of war veterans. Studies of
Vietnam veterans and Nazi concentration camp survivors have added
greatly to the knowledge of PTSD. The National Vietnam Veterans
Readjustment Study (1988) estimated that 31% of the males and 27% of the
females who served in the Vietnam War had symptoms of PTSD. Estimates of
civilian populations put the rate of PTSD at 10% (women) and 5% (men) in
the 15 to 54 age group. Childhood sexual abuse, sexual abuse, and
assault are common causes of PTSD in both military and nonmilitary
women. In 1989 the U.S. Congress created the National Center for
Post-Traumatic Stress Disorder for the study and treatment of PTSD.