Recently, I’ve been talking with more of my clients about the idea of a window of tolerance. What is a window of tolerance you ask? When we’re in our window of tolerance, it does not mean we’re not experiencing stress, anxiety, fear or any difficult emotion. It means that we are able to tolerate those difficult emotions through soothing ourselves, remaining open and connected to ourselves and others. When we are outside of this window, we may react involuntarily from a flight, fight, freeze or fawn response.

Our sympathetic nervous system (SNS) determines how we respond to fear and threats. Our SNS reactions are largely involuntary, and are shaped by our past experiences. When our SNS is threatened, it may take us outside of our window of tolerance, or our ability to cope in a way that is in line with how we’d like to cope ideally – we become dysregulated, if you will.

Let me give a personal example. I have a mostly lifelong phobia of snakes. I believe this phobia started on a kindergarten field trip, when a snake was taken out to show our class and it was slithering on the floor in my direction, backing me into a corner before someone moved it away from me. It’s one of my earliest memories. Now, in that moment, I don’t know if the snake was poisonous or if it could’ve harmed me. I was on a class field trip and the snake was supervised by professional handlers. Most likely, I was not in any danger – the adults in the room were not going to let it harm me. However, my little five-year-old body did not know or understand that, and therefore interpreted that I was in danger. And this interpretation was protective! My body signaled to me that it was potentially in danger and I should do something about it. My SNS was working appropriately based on my five-year-old brain’s level of development and understanding.

Even though my SNS alerted me appropriately in that moment, throughout the remainder of my childhood and adolescence, I could not tolerate any interaction with pictures of snakes, animated snakes, or rubber snakes (ask my sisters about the time they thought it’d be funny to put a fake snake in my bedroom). My heart rate would immediately sky rocket, I would scream and run away from the rubber snake. My SNS had been shaped on that field trip to fear any and all snakes and to see even visual representations of them as threats. As a result, whenever I came across any resemblance of a snake, I went into fight or flight mode.

When I was a sophomore in high school, I was forced into a exposure “therapy” for my phobia – my biology teacher kept a snake in a cage in his classroom. I sat as far away from that cage as I possibly could. However, through that daily exposure, I believe my phobia lessened to the degree that I experience it today. I didn’t employ any specific technique to get through that year of biology. I allowed my discomfort and I chose to sit far away, but ultimately, I was able to tolerate sitting through that class, knowing the source of my fear was in the back corner, but that I could co-exist with it. My sixteen-year-old brain was able to integrate information that my five-year-old brain could not – the snake was in a cage, it was not dangerous, and my teacher knew how to handle it so that it was low risk to keep a snake in the classroom. I wouldn’t say my phobia disappeared completely after that year – I stayed in my seat and refused to touch it or get close when my teacher took it out of its cage (and to this day, almost thirty years later, I still have never entered the snake house at the zoo). But I focused on my classwork, made decisions regarding how I’d cope when the snake come out, and was able to complete the class.

When our SNS becomes active, our parasympathetic nervous system (PNS) comes in handy. The PNS regulates relaxation, rest, and digestion. We can tune into our PNS when our SNS becomes active by connecting with our bodies, whether that’s through deep breathing, meditation, going for a walk, etc. We can evaluate where the threat is – is it something physical, like a real snake on a trail? Or is it something mental or emotional, like a picture of a snake in a book that is causing my heart to race? I can activate by PNS by grounding in the present moment, focusing on my breath, or putting a finger on my pulse to feel it beating. I will probably still want to turn the page or walk by the snake quickly, and it’s fine that I do, I don’t need to look at the snake intently to make the feeling go away. But I’m showing my brain that I can tolerate the discomfort, the surprise, the fear that comes when I unintentionally stumble across a picture of a snake or even a snake out in nature.

I’ve used a concrete phobia as an example in this blog post, but in a lot of cases, the same reaction can be triggered in everyday situations, whether that’s in our place of work or our relationships. If you find yourself feeling challenged to cope with stressors that you feel are having an outsized effect on your mental health or everyday life, I’d encourage you to seek support from a therapist, who can help you develop your own PNS tools of regulation. If you’d like more information regarding how I address this with my clients, feel free to reach out.