ABSTRACT
Post-traumatic stress disorder (PTSD) develops after a person sees, is involved in or hears of an extreme, sudden, unexpected and unavoidable traumatic stressor. The events causing both “acute stress disorder” and PTSD are overwhelming enough to affect almost anyone. The prevalence of PTSD varies according to the exposure to traumatic events of the population studied. The subjective meaning of the trauma to the individual is another important factor that can influence the development or severity of PTSD. Measures of biological variables in clinical populations have supported the hypotheses that the noradrenergic and endogenous opioid systems, as well as the hypothalamic-pituitary-adrenal axis, are hyperactive in some individuals with PTSD. The principal clinical features of PTSD are a painful re-experiencing of the event, a pattern of avoidance and emotional numbing, and fairly constant hyper-arousal. PTSD occurs in children and adolescents, but most studies of the disorder have focused on adults.
