During and immediately following a traumatic event, people may manifest a pattern of dissociative and anxiety symptoms and other reactions, referred to as Acute Stress Disorder. A review of the empirical literature on psychological reactions to trauma suggest that this pattern of symptoms has often been identified across different kinds of traumatic events. It is likely to constitute a psychological adaptation to a stressful event, limiting painful thoughts and feelings associated with the event and allowing the person to function at least minimally. Continuation of these symptoms, however, may impair the person's quality of life and disrupt social and other functioning. If symptoms last beyond a month following the traumatic event, Post Traumatic Stress Disorder (PTSD) may ensue, continuing for months or even years after the precipitating event. Hence, it is important to be able to identify this pattern of reactions that may be manifested in reaction to trauma, so that appropriate intervention can be provided. Although it was not officially recognized in the 3rd edition Diagnostic and Statistical Manual (DSM-III-R), Acute Stress Disorder is included as a separate diagnosis in the DSM-IV.
