In a post following the videoclip last night, I raised a concern for the complex PTSD that US military people may experience post-occupation of Iraqui. Below is an explanation of PTSD - - consider this experience compounded by the horrors of this war. I believe that it will be more intense and produce long-lasting brain changes and troublesome states of mind.
(first of a series)

Post-Traumatic Stress Disorder
by I. Liberzon

When the dust settles after a traumatic event, some people experience a condition marked by intense anxiety, known today as post-traumatic stress disorder. Researchers have recently started to look at the ailment on a biological level and found evidence that it's rooted in the brain, arising from a complex interaction of several chemical and brain area changes. The findings highlight the seriousness of the condition and may lead to new treatments that could help the more than 5 million Americans estimated to have the disorder during the course of a given year.

A plane crashes. Fires erupt. Walls tumble down. You escape the chaos physically unscathed, but how's your brain?

For years, many doctors believed that people who experienced an extraordinarily traumatic or life-threatening event such as a terrorist attack, war or natural disaster should be able to tough it out and move on. Some individuals, however, found that these events stuck with them. They relived the experience through nightmares and flashbacks; had trouble sleeping; and felt detached, depressed and anxious. Today, increasing research indicates that the effects, now collectively referred to as posttraumatic stress disorder (PTSD), are not some sign of a weak personality, but the result of troubles in the brain. The findings are leading to:

An improved understanding of the mental affects of intense stress.
New ways to biologically treat PTSD.

Although the work is still in an early stage, studies indicate that PTSD links to a complex interaction between several chemicals and brain areas.

One of the chemicals involved is corticotropin-releasing factor (CRF), which plays a role in the brain's ability to manage an internal response to daily stressful situations. Many scientists believe that during a stressful event CRF puts your guard up. You may feel extra vigilant, fearful or anxious. CRF also sets off the release of other stress chemicals that arouse various body systems and prepare them to cope with a challenge. In people with PTSD, however, CRF seems to be on perpetual overdrive, possibly creating increased feelings of fear and anxiety. For example, researchers found that, compared with healthy individuals, Vietnam veterans suffering from combat- related PTSD have increased concentrations of CRF.

The vets' intense stressful experience may have inappropriately triggered this CRF boost. In earlier research, infant rats that experience the stress of being separated from their moms end up with increased CRF as adults.

Another example is norepinephrine. It's part of the internal stress response and also may strengthen emotional memory. One study shows that men with PTSD from Vietnam or Desert Storm in Iraq have increased concentrations of this chemical in their cerebrospinal fluid, which bathes the brain, compared with healthy men. The excess norepinephrine may create excess fear and anxiety as well as abnormal memory formation and the flashbacks that PTSD patients experience.

As a next step, scientists are studying ways to target these and other chemicals to prevent or treat the disorder. For example, one drug developed to treat anxiety and depression by blocking CRF activity is currently being tested in people. If successful, it may also benefit those with PTSD. Another drug thought to target the norepinephrine system appears to ward off the development of PTSD, according to a recent small study. Patients took the drug, named propranolol, after they experienced a trauma. Some three months later they had milder reactions to a mental imagery task designed to generate flashbacks as well as the fear and anxiety associated with the original event.

In addition to the chemicals, a variety of brain structures are likely to help produce the memory and emotional symptoms of PTSD. Included are the amygdala and hippocampus, which share connections and normally help maintain healthy formation of memories and emotions like fear. The amygdala in Vietnam veterans with PTSD, however, seems to get overexcited, according to studies. It produces an exaggerated response after patients hear combat sounds, reminiscent of the traumatic time that launched the PTSD. General pictures of scary faces also trigger this exaggerated amygdala response. Furthermore, researchers report some evidence that the hippocampus is smaller in those with PTSD and probably impaired.

Scientists are continuing to examine the underlying components of PTSD to determine how they interact with each other. Added insights into the exact blueprint of the disease won't stop terror but can help uncover increasingly better ways to fight its effects.

The amygdala is thought to help process the emotion of fear and aid memory formation in healthy individuals. The series of brain images below, however, suggest that this brain area in those with PTSD produces an exaggerated response and may contribute to their emotional and memory-related symptoms. Vietnam veterans with PTSD have exaggerated responses in their amygdala (marked with red arrows) after hearing combat sounds, reminiscent of the traumatic time that launched their ailment. Healthy individuals and veterens without PTSD do not have this intense amygdala response.

"Brain Activation in PTSD in Response to Trauma-related Stimuli," by Israel Liberzon et al., Biological Psychiatry, vol. 45, 821, Society of Biological Psychiatry.

Copyright © 2004 Society for Neuroscience