Nervous System

Looking through the ‘Window of Tolerance’

Solidify your understanding of the window of tolerance and the impact that trauma can have on it. What happens when we are pushed outside that window?
Written by Poppy S.

What is the window of tolerance?

When someone talks about the ‘Window of Tolerance’ they are referring to the optimal zone of arousal in the nervous system, or the balanced spot between hyperarousal and hypoarousal. When we are in our own window of tolerance, we are able to act rationally and regulate our emotions. This concept has been developed by Dr Daniel Siegel and has strong foundations in neuroscience.

Why does the window of tolerance differ from person to person?

The window of tolerance is not necessarily fixed, and it differs in size from person to person. There are a number of things which can influence the window of tolerance and the ways in which we react if pushed beyond our boundary. For example, temperament, history of trauma, social context, physiological state, and state of mind.

Narrow window of tolerance meaning

In clients who have experienced trauma, the window of tolerance is narrower. This can result in them being primed towards detecting threats and having difficulty regulating their emotions. A stressor or trauma trigger can create what may seem like an overreaction from the outside but in reality they have been pushed past the boundary of their window of tolerance.

The window of tolerance is affected in trauma survivors because when trauma is experienced, the nervous system goes into a protective, survival state. This alters a person’s sense of safety and as a result, can narrow their window of tolerance. In cases of complex childhood trauma, the window shrinks over time due to impaired functioning of the body and mind. In cases of complex adult trauma the window narrows as a result of increased emotional dysregulation.

Experiencing things that we consider to be hurtful, anxiety inducing, anger causing or painful can drive us to the edge of the window. People with a wider window of tolerance may be able to stay within their window and feel comfortable despite experiencing high degrees of emotional intensity.

What happens when we ‘open’ or go outside our window of tolerance?

The body’s response to going outside the window of tolerance can be explained by looking at the function of the autonomic nervous system (ANS). The window of tolerance has an upper and a lower boundary so people can be pushed out of their window in two directions.

The impact of hyperarousal

If pushed above the upper boundary we enter a state of hyperarousal, otherwise known as the fight or flight response. This means we have excessive activity in the ANS and an increase in energy consuming processes. This often makes people feel anxious, jittery and unable to control angry outbursts. It is accompanied by physical symptoms such as tightened muscles. In post-traumatic stress disorder (PTSD) people experience flashbacks and nightmares when they are in a state of hyperarousal.

The impact of hypoarousal

If pushed below the lower boundary of our window, we enter into a state of hypoarousal or “collapse”. There is a decrease in physiological processes such as heart rate and respiration rate, it can lead to feelings of depression, dissociation, and numbness. When clients with PTSD are in a state of hypoarousal they can suffer from memory issues and feelings of depersonalisation.

Can the window of tolerance be widened?

Having a narrow window of tolerance can hinder therapeutic progress for a client. However, as the window of tolerance isn’t fixed, it is possible to widen it. A client must first be guided to recognise their window of tolerance and associated symptoms. They can then be taught techniques for re-regulation of their ANS.

There are a number of different therapeutic approaches a clinician can take depending on whether their client is in a state of hyperarousal or hypoarousal.

When working with a client who is in a hyperaroused state you may consider going at a slow, gentle pace. It may also be beneficial to work with techniques focused on as breathing, meditation or anger management.

Alternatively, when working with hypoarousal you are trying to increase the energy in the room. As a clinician, you can be mindful of your volume of speech, your tone and your physicality to raise this energy. To guide a client out of a dissociative state you can use techniques such as describing something in the room to anchor them or cognitive scaling to help them to better understand their levels of arousal.

Discover more:

If you would like to learn more about the window of tolerance in context watch Daniel Siegel’s video course 

Written by Poppy S.
October 4, 2023
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