“…In this reaction, the brain is engaging in what seems to be an exaggerated form of pattern recognition, a common form of learning in which similar patterns of stimuli call forth a similar neuroendocrine (and, thus, behavioral) response. 4,5 Symptoms can be grouped into 3 main behavioral clusters: (1) reexperiencing through intrusive thoughts, dreams, and "flashback" recollections; (2) avoidance of reminders and numbing of responsiveness, including social withdrawal, restricted range of affect, and constriction of play; and (3) physiological hyperarousal in the form of hypervigilance and exaggerated startle response, attention and concentration problems, and sleep disturbance. When disordered stress responses persist long after the trauma, the condition is termed PTSD.…”