[PTSD]

Post-traumatic stress disorder (PTSD) is a term for certain severe psychological consequences of exposure to, or confrontation with, stressful events that the person experiences as highly traumatic. Clinically, such events involve actual or threatened death, serious physical injury, or a threat to physical and/or psychological integrity, to a degree that usual psychological defenses are incapable of coping with the impact.

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PTSD is thought to be primarily an anxiety disorder (possibly closely related to panic disorder) and should not be confused with normal grief and adjustment after traumatic events.

PTSD may be triggered by an external factor or factors. Its symptoms can include the following:
nightmares
flashbacks
emotional detachment or numbing of feelings (emotional self-mortification or dissociation)
insomnia
avoidance of reminders and extreme distress when exposed to the reminders ("triggers")
loss of appetite
irritability
hypervigilance
memory loss (may appear as difficulty paying attention)
excessive startle response
clinical depression
anxiety

...PTSD has three subforms: Acute PTSD subsides after a duration of three months. If the symptoms persist, the diagnosis is changed to chronic PTSD. The third subform is referred to as delayed onset PTSD which may occur months, years, or even decades after the event.

Experiences which may induce the condition

* childhood physical, emotional or sexual abuse, including prolonged or extreme neglect; also, witnessing such abuse inflicted on another child or an adult

* experiencing an event perceived as life-threatening, such as: a serious accident; medical complications; violent physical assaults or surviving or witnessing such an event, including torture; adult experiences of sexual assault or rape; warfare; violent, life threatening, natural disasters; incarceration

For more info, read about PTSD here. God bless wikipedia lol.