The physical and emotional reaction to trauma that later develops into PTSD in some people is really a way to survive during intense danger. The body produces chemical substances which prepare people to fight or run when they are under threat. They become very alert, but at the same time, they shut down emotionally. This is called numbing. It happens because emotions like love or sadness would only get in the way of physical survival. Many times people in the middle of danger seem extremely calm. They have disassociated from themselves, experiencing the event as if they were watching a movie of someone else experiencing what is happening around them.
Long after the traumatic event has passed, some people continue to experience the trauma response. Professionals who study and treat PTSD separate the symptoms of the disorder into three categories that include:
Things that cause a person to involuntarily re-experience the traumatic event. These include nightmares, flashbacks, and intrusive memories.
The avoidance of anything that will trigger memories of the trauma, such as sights, smells and sounds associated with the trauma and even certain feelings. Often people with PTSD withdraw from activities they used to enjoy.
Signs that the person is both emotionally and physically in a state of constant readiness in case the trauma happens again. Anger, the need to control everything in their lives and jumpiness are some of these signs.
Straight Talk about Post Traumatic Stress Disorder by Kay Marie Porterfield details the symptoms of PTSD and how they affect the lives of those who have been traumatized.