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Post-traumatic Stress Disorder (PTSD) (cont.)

What Are PTSD Causes?

When you are afraid, your body activates the "fight or flight" response, a response common to other animals as well as our evolutionary ancestors. With this response, the brain activates the sympathetic nervous system, including the release of adrenaline (epinephrine) in the body, which is responsible for increasing blood pressure, heart rate, and increasing glucose to muscles, readying the body for a physical response (fight or flight). However, once the immediate danger (which may or may not have actually existed) is gone, the body begins a process of shutting down the stress response, and this process involves the release of another hormone known as cortisol.

If your body does not generate enough cortisol to shut down the flight or stress reaction, you may continue to feel the stress effects of the adrenaline. Trauma victims who develop post-traumatic stress disorder often have higher levels of other stimulating hormones (catecholamines) under normal conditions in which the threat of trauma is not present as well as lower levels of cortisol. This combination of higher than normal arousal levels and lower than normal levels of the calming hormones of the changes creates the conditions for PTSD.

After a month in this heightened state with stress hormones elevated and cortisol levels lowered, you may develop further physical changes, such as heightened hearing. This cascade of physical changes, one triggering another, suggests that early intervention may be the key to heading off the effects of post-traumatic stress disorder. Not everyone exposed to a trauma has an abnormal reaction, and some who initially experience symptoms find that they resolve in a relatively short period of time. The presence of PTSD symptoms lasting one month or less after a trauma is known as acute stress disorder. Another area of research is to understand why some people are able to recover, while others develop the long-term difficulties of PTSD.

Specific brain regions are also associated with PTSD and the physical responses in the rest of the body. The amygdala is a deep brain region that is highly sensitive to detecting possible threats based on input from our senses. When activated, it alerts the body to danger and activates hormonal systems. The hippocampus is the structure associated with memory formation. Abnormal memory consolidation may also be associated with a risk for PTSD. Some studies showed that a reduction of hippocampus volumes are related to PTSD.

Medically Reviewed by a Doctor on 9/11/2017
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Posttraumatic Stress Disorder »

The formal diagnosis of posttraumatic stress disorder (PTSD)was not introduced into the Diagnostic and Statistical Manual of Mental Disorders until its third publication in 1980.

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