Have you ever been in a situation that triggered such an intense emotional response that you felt like you were completely taken over, losing all control?  It almost felt like you were having an out-of-body experience, dissociating from yourself and your surroundings? Maybe you experience extreme rage, lashing out, and yelling, or you may feel completely numb and unable to react.
When stress triggers reactions like irritability, panic, rage, or conversely, a sense of numbness, disconnection, or freezing, you may have stepped outside your “window of tolerance.” This window is where you operate at your best and can even thrive. Mental Health Professionals believe that understanding and managing your emotions is key for overall emotional well-being and improving your mental health.
What is the Window of Tolerance?
The Window of Tolerance was developed by Dr. Dan Siegel. It refers to your emotional experience and the optimal range of emotional and physiological arousal within you that can effectively cope with stressors. In this zone, you can experience and process emotions without becoming overwhelmed or shutting down. If your arousal falls outside the window, you experience intense emotions and may enter either a Hyper-aroused state (fight or flight response) or a Hypo-aroused state (freeze or dissociation). 
What happens when you exceed your Window of Tolerance?
When the amygdala (the survival part of the brain) is activated, it will put you in a state of fight/flight(hyperarousal) or freeze (hypoarousal). Safety is your priority in this state, and emotional regulation takes a back seat as the prefrontal cortex (reasoning

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