The Window of Tolerance
Thinking about distress and dysregulation, and why 'anxiety' doesn't describe everyone's experience.
I've been hearing a lot of discussion about anxiety lately—people sharing their experiences of chronic anxiety and discussing strategies for managing intense anxiety episodes. It’s so valuable to have these conversations openly! However, my own experiences of distress, and those of many others I support, don't always align with this anxiety narrative. In trying to articulate my experiences and make sense of where they fit in, I remembered a concept I came across a few years ago but hadn't explored deeply: the window of tolerance.1
Let me begin with a recent personal experience to illustrate: I facilitate a monthly neurodivergent support group through a local organisation. On the morning of these meetings, I often feel a bit anxious as I think about what I need to organise, who might attend and how I might manage any issues that arise. My heart rate increases, my stomach flutters, and I feel restless. Facilitating this group well is important to me, so my sympathetic nervous system kicks in, flooding my body with stress hormones to keep me alert and focused, ready to tackle whatever comes.
However, last week looked a bit different. The morning of my workshop was unusually hectic, with various logistical challenges as I juggled taking my child to a junior triathlon before the support group meeting. Despite the joy of watching her compete, the sensory intensity of the event added to my stress. On arriving at the support group venue, I encountered further obstacles—my booked room was unavailable due to ongoing construction, and administrative staff were tied up elsewhere. This series of stressors pushed me beyond my usual coping threshold, triggering a cascade of overwhelming thoughts and emotions.
This is where the window of tolerance (aka the “optimal arousal zone”) comes in - we all have a range of stress or emotional activation within which we can function well, engaging socially and problem-solving to the best of our abilities. It’s really healthy and normal to fluctuate within this window throughout each day, with our sympathetic nervous system energising us when needed and our parasympathetic nervous system bringing us back to a calm state. The range we can tolerate depends on a lot of things, but it’s worth being aware that people with trauma histories2 and those with neurodivergent traits often have a narrower window of tolerance and larger fluctuations within it.3 So, extra relevant with the people I’m mostly supporting in my work.
When stressors push us beyond the upper boundary of our window of tolerance, whether through one significant event or an accumulation of stress, we experience hyperarousal. This is the tense, hyper-vigilant, reactive kind of state where all our sympathetic nervous system is in overdrive, preparing us for ‘fight or flight’. So, y’know, super helpful if we’re encountering a genuine threat to safety that we need to react to! While our body is set to act fast, it also hinders our ability to think in creative, nuanced ways and engage socially - so it’s not so beneficial in the situations we typically associate with stress and anxiety.
But for some of us, in response to high levels of stress, our bodies instead enter hypoarousal, where the parasympathetic nervous system takes over to protect us from that overwhelm… bringing us right down below our window of tolerance and effectively shutting us down. This ‘freeze or flop’ survival response might be experienced as low mood, energy, and motivation, often accompanied by feelings of hopelessness or a dissociation from the present situation.
I’ve heard people talk about generalised anxiety disorder and depression as two sides of the same coin, and this concept illustrates it well - anxiety as a chronic hyperarousal state, and depression as the responsive, chronic, hypoarousal state.
For me, hypoarousal tends to dominate under stress, as it did on that particular day last week. In that moment of peak stress, my mood plummeted, and I struggled to hold back tears. My thoughts rapidly turned towards hopelessness - How can I support neurodivergent people if it’s too hard for me, as a neurodivergent person myself, to navigate these systems? Is anyone even going to come anyway? Shall I just give up and go home?
In that moment, with my thoughts spiralling and my emotions overwhelming me, I wasn't equipped at all to problem-solve. My brain felt like it had hit a wall, rendering me incapable of finding a solution to the room booking dilemma. To prevent a public meltdown, I hastily retreated to a nearby park, where I employed every coping mechanism I knew. Grounding exercises, calming distractions—I worked through them all until I regained my composure and returned to my window of tolerance, ready to navigate the change in plan. By the time the group session began, I was organised, settled and back on track.
To be able to put words to this type of dysregulation not only helps me understand my own experiences under stress and history of depression, but also makes sense of the variety of responses to stress. Rather than compartmentalising "having anxiety" or "having depression", perhaps we’d do better to recognise the nuanced ways our bodies and minds react to stressors. By understanding our own windows of tolerance and learning to recognise where our current emotional state is at, we can better develop effective coping mechanisms and regulation strategies to suit our own needs and support others in doing the same.
Do you ever find yourself outside your window of tolerance? How would you describe your mental, emotional and physiological state during those times? What strategies help you return to your window of tolerance?
The concept of the window of tolerance was coined by clinical professor of psychiatry Dan Siegel in his 1999 book The Developing Mind.
Clinically (and in Siegel’s work) this concept is mostly used when working with people who have experienced trauma and the importance of keeping the client within their window and feeling psychologically safe for effective trauma therapy.
The wonderful Dr. Neff of Neurodivergent Insights wrote a piece about the window of tolerance in relation to autism and ADHD.