
Post-traumatic Stress Disorder (PTSD)
Someone asked me to give more information about PTSD, so I thought I would do a couple posts about it. After depression and substance abuse, PTSD is one of the most prevalent mental disorders. An estimate of 70% of people in the US are exposed to a traumatic event in their lifetime (car accident, combat, physical/sexual assault), but only about 14-24% of these people will develop PTSD. It has slightly higher prevalence for women (10-14%) than men (5-6%), but is much higher in soldiers than civilians. For instance, 30% of Vietnam veterans had PTSD and almost half of prisoners of war developed PTSD in their lifetimes.
It is important to note that PTSD cannot be diagnosed until 30 days after a traumatic event, since some of the symptoms are “normal” to be seen immediately following the event. It is their persistence that creates a problem.
The criteria for diagnosis of PTSD are:
Criterion A - Exposure to a traumatic stressor.
Criterion B - Re-experiencing symptoms.
Criterion C - Avoidance and numbing symptoms.
Criterion D - Symptoms of increased arousal (i.e. hyper-vigilance).
Criterion E - Duration of at least one month.
Criterion F - Significant distress or impairment of functioning.
In the image above taken from the NIMH site, you can see the VMPFC and amygdala are highlighted. That is because the amygdala creates a fear response and the VMPFC is able to extinct a fear response. In PTSD, it is thought that this system is somehow hindered and the individual is unable to extinct the fear response.