What Causes PTSD?

By Harold Cohen, Ph.D.

Explanations of PTSD focus primarily on the way that the mind is affected by traumatic experiences. Theorists speculate upon facing overwhelming trauma, the mind is unable to process information and feelings in a normal way. It is as if the thoughts and feelings at the time of the traumatic event take on a life of their own, later intruding into consciousness and causing distress.

Pre-traumatic psychological factors (for example, low self-esteem) may make this process worse (for example, low self-esteem may be reinforced by a brutal rape). Post-traumatic reactions by others (for example, a raped woman who is viewed by family as “dirty”) and by the self (for example, physical discomfort caused by memories of the rape) may also play a role in influencing whether such symptoms persist. It is hypothesized that only after successful reprocessing of the traumatic event(s) do PTSD symptoms decrease.

In addition, powerful new techniques for studying the brain, its structures and its chemicals are providing scientists with information on the how both brain and mind are important in the development of PTSD. Recent brain imaging studies place emphasis on two brain structures: the amygdala and hippocampus. The amygdala is involved with how we learn about fear, and there is some evidence that this structure is hyperactive in people with PTSD (this can be conceptualized as a “false alarm”). The hippocampus plays an important role in the formation of memory, and there is some evidence that in people with PTSD there is a loss of volume in this structure, perhaps accounting for some of the memory deficits and other symptoms in PTSD.

Other research has focused on the neurochemicals that may be involved in PTSD. For example, there is evidence that a hormonal system known as the hypothalamic-pituitary-adrenal (HPA) axis becomes disrupted in people with PTSD. This system is involved in normal stress reactions, and its disruption in people with PTSD can again be conceptualized as a kind of “false alarm”. Some scientists have suggested that dysfunction of the HPA system results in hippocampal damage in people with PTSD. Medication presumably acts to reverse neurochemical dysfunction in PTSD; it is as if these agents switch off the “false alarms” of which this condition is comprised.

Ultimately, it may even be possible to predict the development of PTSD based on the early psychological and neurochemical changes in people who have been exposed to a traumatic event. Continued research also offers the promise of new treatments for PTSD in the future.

 

APA Reference
Cohen, H. (2006). What Causes PTSD?. Psych Central. Retrieved on July 26, 2014, from http://psychcentral.com/lib/what-causes-ptsd/000162
Scientifically Reviewed
    Last reviewed: By John M. Grohol, Psy.D. on 30 Jan 2013
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