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Day # 103: Introduction to Post-Traumatic Stress Disorder (PTSD)

We are continuing our current theme of trauma and stressor related disorders. Within this theme we will now shift our focus to covering PTSD in more depth. Today we will discuss an introduction, definitions, and the diagnostic criteria in more detail.

Today's Content Level: Beginner; Intermediate


Overview 1, 2

  • The psychological response following exposure to a traumatic/stressful event can be variable and may include a normal stress response or a wide range of psychological symptoms.

  • Post-traumatic stress disorder (PTSD) is the development of characteristic symptoms following one or more traumatic events.

  • The essential features of PTSD are the traumatic exposure and the development of co-occurring symptom clusters to include re-experiencing, avoidance, negative alterations in thoughts/mood, and increased arousal. See diagnostic criteria below.

  • PTSD can be an emotionally devastating condition as individuals "re-live" distressing aspects of the traumatic event and often organize their lives in an attempt to avoid and minimize the persistent effects of the trauma. They are unable to distance themselves emotionally from their traumatic experiences. It feels ever-present and powerful in their lives.

What Is Trauma, Anyway? 3

  • Many of our patients have experienced adverse events, but it is important to understand what meets the criteria of exposure to a "trauma" according to "criterion A" in the DSM-5.

  • Trauma = exposure to actual or threatened death, serious injury, or sexual violence.

  • The exposure must occur in one of the following ways

    • Direct experience

    • Witnessing the event(s) in person

    • Learning that the event(s) occurred to a loved one (must be violent or accidental)

    • Experiencing repeated or extreme exposure to aversive details of the traumatic event(s) (does not apply to exposure through pictures or electronic media unless the exposure is work-related)

  • Examples include physical assault, severe motor vehicle accidents, rape / sexual violence, combat, being kidnapped, taken hostage or incarceration as a prisoner of war, terrorist attack, torture, natural or human-made disasters, and first responders collecting human remains.

History 4

  • Traumatic syndromes resembling PTSD have been described and debated throughout history. This is an interesting topic and deserves an entire article, but here are some highlights.

  • PTSD is a relatively new terminology, but many scholars argue that there is ample evidence that this syndrome was seen and described millennia ago. Recently discovered mesopotamian texts more than 3,000 years old reveal that combat-related PTSD may be as ancient as combat itself.

  • In a fascinating book titled "Achilles in Vietnam", the author examines the psychological devastation of war by comparing the soldiers of Homer’s Iliad with Vietnam veterans suffering from PTSD.

  • In the American Civil War some soldiers were described as "trembling, staring into the middle distance and jumping at any loud noise". WW1 survivors were labeled with "shell shock" and "war neurosis". "Shell shock" was a term that suggested traumatic brain injury as the cause of symptoms, whereas "war neurosis" suggested a psychological origin. They were described as having a "thousand yard stare". In WW2 the term "combat fatigue" or "combat stress reaction" was used by the US army. Other terms later presented included Kardiner's description of "traumatic neuroses" and Horowitz's "stress response syndrome".

  • DSM: Traumatic stress disorders were not included in the first two versions of the DSM despite the clinical observations during the world wars. The introduction of PTSD first occurred in DSM-III (1980) after observations of the psychopathology seen in the Vietnam War.


  • Exposure to actual or threatened death, serious injury, or sexual violence. Exposure may occur through direct experience or witnessing the trauma (see "what is trauma" above for details).

  • Timing: Trauma occurred at any time in the past. Symptoms last > 1 month. Contrast this with acute stress disorder (trauma occurs < 1 month ago and symptoms last > 3 days and < 1 month).

  • Intrusive symptoms (≥1): recurrent and intrusive re-experiencing of the event. Can occur via memories, nightmares, or "flashbacks" (dissociative reactions). May include intense psychological distress or physiological reactions to cues relating to the trauma.

  • Avoidance behaviors (≥1): active and persistent avoidance of reminders of the trauma which can include internal (memories/thoughts/feelings) and external (people/places/conversations/activities/situations) reminders.

  • Mood/Cognitive alterations (≥2): negative alterations of mood or cognitions can include amnesia, negative beliefs about self/others/world, distorted sense of self-blame, persistent negative emotions (guilt, fear, anger, etc.), anhedonia, feelings of detachment or isolation, and inability to experience positive emotions.

  • Arousal/Reactivity alterations (≥2): increased arousal/reactivity manifested in a number of possible ways such as irritability/anger, reckless behavior, hypervigilance, exaggerated startle response, difficulty concentrating, or insomnia.

  • Specifiers

    • With dissociative symptoms. Depersonalization = feeling of being detached from your mental process or body. Derealization = feeling of unreality of surroundings. Make sure this is not due to substance use or another medical condition.

    • With delayed expression. If the full diagnostic criteria are not met until >6 months after the event.


    • Traumatic event

    • Re-experience

    • Avoidance

    • Unable to function

    • Month or more of symptoms

    • Arousal increased

  • The above criteria applies to adults and children > 6 years old. For children ≤ 6 years old the symptoms are very similar with some nuanced differences. Re-experiencing may not be reported in the form of distressing visual flashbacks but can be seen in re-enactment of trauma in play, drawings, or nightmares. Certain types of avoidance may not be seen due to insufficient abilities with abstract cognition or verbal expression. See the DSM-5 for complete differences.


Thanks for reading. I hope you found it helpful. I believe that a daily dose of learning goes a long way! Next up will be a discussion about the epidemiology, pathogenesis, and course/prognosis for PTSD.

Resources for this post include Pocket Psychiatry, Kaplan and Sadock's comprehensive psychiatry, DSMV, and First Aid For the Psychiatry Clerkship as well as the articles referenced in the post.

Bullet Psych is an Amazon Associate and we receive a small commission if you use our links.

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