All organism tend to be in a state of equilibrium (homeostasis). When something threatening disturbs the homeostasis human brain sends out all kinds of alarms and we become hyper aroused (Hyperarousal is characterized by heart racing, sweating, changes in attention and sensory awareness (we look for specific clues, get easily startled, etc.), and we feel fear or anger) in order to preserve ourselves (fight of flight actions). In most cases, we recover shortly after the event and we go back to homeostasis. 

However, after prolonged and/or repetitive exposure to traumatic events (Traumatic events have the quality of danger as they include threatened death and/or serious injury) a balanced condition may not be re-established and the organism stays in the prolonged state of “red alarm” (allostasis) even though the crisis has long ended. 


In this state of alarm, re-experiencing, avoidance and hyperarousal symptoms are dynamically interrelated in an attempt to seek stability in functioning following a change in the balanced baseline.

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What does that mean for you and the person you care for?

For example, a reminder of a traumatic stressor, e.g. seeing news footage on sexual abuse, will activate the memories on the trauma (re-experiencing), which in turn will activate the physiological response of fight or flight, such as changes in heart rate and affect (hyperarousal, heightened sense of threat). The unpleasantness of the feelings leads to conscious effort not to think about this trauma or to other coping strategies such as  alcohol abuse (avoidance).

Persons with PTSD in the survival mode are constantly on the guard, troubled by memories and physical reactions which they cannot control. They have problems sleeping, easily become irritated, and often feel better when they are isolated from the world.