"Window of Tolerance" a term coined by Dr. Dan Siegel is commonly used to understand brain/body reactions to events. Our personal 'window' is unique to us and is set by they way we have learned to manage our emotions. We have operate within it and manage life's ups and downs.
Outside of this is when we can cope less well, you find you move upwards (on the diagram) or downwards. It's useful to remember the triggers you experience that moves you outiside of your own window.
Hyperarousal is characterised by anxiety, panic, fear, hypervigilence, emotional flooding etc. This keeps our system stuck and effects our ability to relax. It can often make it difficult to sleep, eat and manage our emotions.
Hypoarousal is characterised by exhaustion, depression, flat affect, numbness, disconnection, dissociation etc. We may want to sleep all the time, it asloimpacts our appetite and digestion and may make us feel emotionally deadened.
Once we have recognised what might cause us to move into hyperarousal or hypoarousal we can learn to manage those events or reduce exposure to them. There are also ways to help you widen your window or move back into your comfort zone.
Activities to try:
Breathe using your stomach muscles
Sip a drink
Do some light exercise
Listen to soothing music
Eat comforting food, like soup or hot chocolate