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Posttraumatic Stress Disorder

  1. Mark W. Miller,
  2. Brian P. Marx,
  3. Terence M. Keane

Published Online: 30 JAN 2010

DOI: 10.1002/9780470479216.corpsy0699

Corsini Encyclopedia of Psychology

Corsini Encyclopedia of Psychology

How to Cite

Miller, M. W., Marx, B. P. and Keane, T. M. 2010. Posttraumatic Stress Disorder. Corsini Encyclopedia of Psychology. 1–3.

Author Information

  1. VA Boston Healthcare System and Boston University School of Medicine

Publication History

  1. Published Online: 30 JAN 2010


Posttraumatic stress disorder (PTSD) is a psychiatric disorder defined by symptoms reflecting disturbances in cognitive, behavioral, and physiological functioning that develop in the wake of exposure to a psychologically traumatic event. According to the DSM-IV-TR (American Psychiatric Association, 2000), the diagnosis applies to individuals who develop a requisite number of symptoms after experiencing, witnessing, or being confronted with an event that involved perceived or threatened loss of life, serious injury, or loss of physical integrity and that evoked fear, helplessness, or horror (e.g., military combat, sexual or physical assault, serious accidents, and major disasters). DSM-IV-TR organizes the symptoms of PTSD under three clusters: (1) reexperiencing (e.g., intrusive thoughts, nightmares, flashbacks, and psychophysiological reactivity to reminders of the trauma), (2) avoidance and emotional numbing (e.g., avoiding stimuli associated with the trauma and inability to experience a full range of emotions), and (3) hyperarousal (e.g., hypervigilance, exaggerated startle response, and sleep disruption). By definition, these symptoms must persist for more than 1 month after the trauma and produce clinically significant distress and/or impairment.


  • PTSD;
  • trauma;
  • diagnosis;
  • treatment