3.5 The window of tolerance
Every individual has what is known as a ‘window of tolerance’. This means that there is a state of physical and emotional arousal that is tolerable and bearable, and when a child is within his or her window of tolerance, she or he can think, learn, love and relax. Most people can identify times when they have been outside the boundaries of their window of tolerance. At these times thinking or behaviour has become disrupted by intensified emotional and physiological arousal. Behaviours during these times are not normally chosen, and a lack of flexibility in responses is common. Either excessive rigidity or chaos are typical during these dysregulated episodes.
For traumatised children, small ‘every day’ things (like a parental request to brush their teeth, or a change of one classroom to the next) spirals them out of their window of tolerance. Traumatised children then swing into being hyper-aroused (overly aroused) or hypo-aroused (under aroused). You can expect traumatised children to be over or under aroused for most of the time and, in either state, their behaviour is out of their hands; they simply cannot control it no matter how hard they try. Their brain is not wired correctly and they do not have the ability to switch off behaviour. They are in automatic survival mode and they cannot think, reason or rationalise when feeling under threat.
overshooting the window: Hyperarousal
Many traumatised young people have difficulty finding stillness. You might have noticed their darting eyes and a tendency to fiddle with something in their hands or how easily they startle. You might even notice yourself feeling a little stirred up or ill at ease when around them. You notice this because their internal system that is primed to act to protect itself is communicating with your nervous system. These young people are likely to engage in actions such as fight or flight in the face of threat. We can expect them to move toward or away when they feel unsafe. These protective actions are deeply ingrained in the most primitive part of their brains and they have likely been used successfully in the past by the young person to help keep themselves safe.
Children who are overly-aroused are in fight/flight. They run, hit, scream, shout, bite, spit, say hurtful words, avoid, squirm and disrupt. The brain says, “I’m in danger” and their body responds. Some physical cues suggesting too much arousal and an overshooting of the window of tolerance include:
- dilated pupils (to let light in to see better)
- lack of saliva making the mouth dry
- shallow breathing
- butterflies in the stomach
- faster heart beat
- excessive sweating
- tensed muscles (readied for action)
- agitated movement
- difficulty finding stillness.
Case example – Gary
The bell sounds ending lunchtime. The teacher rushes towards her year nine class having missed lunch to handle a yard duty incident. Distracted and rushed she moves into the classroom and the students flow in b