Window of Tolerance

Lesson objective:

When stress overwhelms us, there appears to be a window of tolerance. What is it and what does it entail?

In the face of chronic stress and trauma, various regions of the brain, the HPA axis, the autonomic nervous system, and most of the physical body are overwhelmed with signals and adaptations intended to help you confront stress and to help keep you alive. 

All of these well-intentioned adaptations over time leave confusing and often contradicting effects in the brain, body, and behavior.

Trauma is basically a form of reaching allostatic load, of being overwhelmed by changes to the physical body and brain. Some researchers describe allostasis as “body budgeting,” and trauma spends much of that budget in a very short time.

Basically, trauma and stress may force the body to “turn off” some of its stress response into the future, to cope with the overload of the present. Or on the other side, the brain and body may stop spending energy on certain tasks in the here and now, in response to predictions of future danger. 

Reaching allostatic load–or the brain and body being maxed out–lead to all sorts of contradictory and alternating feelings, going between highs and lows, between loving connection and numbness, between feeling present in the body and then totally disconnected from the body

Any dysfunction or maladaptation of the stress response can create problems for you. For example, too much cortisol seriously affects how you think and how you feel. Too much attention to possible threats can make every day difficult, in a world full of imagined risks. Numbness, in contrast, may make relationships difficult. Any and all of these disruptions can have negative consequences.

In the aftermath of stress and trauma the brain, body, and behavior have a harder time regulating. 

You may feel “okay” or “regulated” less often, going between high and low responses to the world around you. 

Many researchers describe this phenomenon with a concept called the window of tolerance

The window of tolerance describes the zones of arousal, meaning stimulation or feeling, that a person may experience.

The window of tolerance includes 

  • the hyperarousal zone
  • the optimal (or tolerable) arousal zone
  • And the hypoarousal zone

We will start in the middle. The middle is the optimal arousal zone, where a person feels capable of confronting stressful situations. In this zone, the body is able to respond effectively and efficiently to stress and to the outside world in general. This zone is not free of stress or discomfort entirely, but in this zone an individual can deal with stressful situations without getting overwhelmed. 

The top zone is the zone of hyperarousal, of hypervigilance, of threat sensitivity, where the brain and body are on edge, ready to act in the form of fight-or-flight responses. In this state, you may feel anxious, angry, overwhelmed, high energy, disconnected and chaotic. At this point, you know the various biological and physiological processes that lead to these states of hyperactivity and hypervigilance. 

The bottom zone is the zone of hypoarousal, of numbness, of feeling frozen, where the brain has adapted by shutting down various processes to keep you safe. You may feel lethargic, depressed, detached, and disinterested. And as with hyper- responses, you now know much of the biological and physiological processes that cause these flat or blunted responses.

As said, each person who has been through stress and trauma has a different experience. 

It is important to note that some people consistently operate with elevated or hyper- responses. Others may be consistently low, with hypo- responses in the brain, body, and behavior. Some people may rapidly and wildly fluctuate between levels, yet rarely operate in the middle, tolerable zone. Overall, while the dysregulation caused by stress and trauma looks and feels different from person to person, there is no question that it can be incredibly tiring and uncomfortable to operate outside the zone of tolerance. And as we move forward, we will focus on strategies that can help you direct your brain and body back into the middle zone, the zone of tolerance, when you feel dysregulated.