Understanding the Window of Tolerance: Why You Shut Down or Blow Up

The “window of tolerance,” developed by Dr. Dan Siegel, describes the range of arousal within which the nervous system can effectively function. When you’re inside your window, you can think clearly, feel your emotions, and respond flexibly. When stress or trauma push you outside that window, you may move into hyperarousal (fight/flight) or hypoarousal (freeze/shutdown). 

Hyperarousal feels like anxiety, agitation, or anger—the nervous system is on high alert, scanning for danger. Hypoarousal feels like emotional numbness, exhaustion, or disconnection—a kind of collapse. Both are protective, adaptive responses rooted in survival.

For individuals with trauma histories or chronic stress, the window of tolerance can become narrow. Everyday stressors may quickly trigger reactivity or shutdown. Therapy helps by identifying triggers and teaching self-regulation skills to expand that window over time. 

Grounding techniques, deep breathing, and body-based practices help regulate arousal in the moment. Over time, developing interoceptive awareness—understanding what your body feels like when calm versus dysregulated—helps individuals catch signs early.   

Understanding your window of tolerance builds emotional intelligence and self-compassion. Rather than judging yourself for “overreacting” or “numbing out,” you begin to see these as signals that your nervous system needs support. Learning to return to your window fosters resilience, stability, and deeper connection with others.