PTSD is associated with three core symptom clusters, re-experiencing, avoidance and numbing, and hyperarousal. It also presents a complex set of other symptoms, including insomnia, depression, anxiety, substance abuse, and problems in interpersonal relationships.
Hallmark is persistently re-experiencing the traumatic event in one or more of the following ways:

1. Recurrent and intrusive distressing recollections of the event, including images, thoughts, or perceptions.

In young children, repetitive play may occur in which themes or aspects of the trauma are expressed.

2. Recurrent distressing dreams and nightmares of the event.

Children may have frightening dreams without recognizable content.

3. Acting or feeling as if the traumatic event were recurring (includes a sense of reliving the experience, illusions, hallucinations, and dissociative flashback episodes, including those that occur on awakening or when intoxicated).

Young children may reenact the trauma.

4. Intense psychological distress at exposure to internal or external cues that symbolize or resemble an aspect of the traumatic event.



5. Physiological reactivity on exposure to internal or external cues that symbolize or resemble an aspect of the traumatic event.