PTSD patients most commonly have experienced horrific event such as wartime combat, being kidnapped or raped, or imprisonment in a concentration camp. The recurrence of nightmares is one of the ways that PTSD patients reexperience the event. However, the causal effect of nightmare due to these events is still unclear while these dreams are distinct from the dreams of chronic nightmare sufferers. The major difference in the content of the dreams between the two types sufferers is that the content of the traumatic nightmares are exactly similar to the actual events. Traumatic nightmare takes place mainly during REM sleep but it can also take place during stage two sleep as well. Posttraumatic nightmares are often repetitive, accurate replays of trauma, accompanied by affective, physiological, and behavioral responses. According to a study patients are likely to report having nightmares earlier in the sleep cycle and to claim that arousal and gross body movement are accompanied during nightmares. This suggests that the traumatic nightmare is a separate phenomenon, intermediate between REM-nightmare and the stage-4 night terror(if you have you have questions about sleep and its mechanism).
In case of war veterans the likelihood of developing PTSD was greater for those who were involved in combat compared to the ones that were not. There is also an age difference, the veterans with post-traumatic nightmares had a mean age of just under eighteen, at the time of their sever trauma, whereas veterans who did not develop these nightmares had a mean age of twenty-one at the time of their most severe experience.
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Other types of Nightmares