The Window of Tolerance - A (Very Basic) Introduction to Polyvagal Theory
Sienna Chu, MHC
The more we’ve come to learn about trauma, both big T and little t, the more we’ve been able to learn about the relationship between mind and body and how both work together in supporting our survival and growth. Science has helped us better understand the specific physiological responses that take place in our bodies when we experience (or perceive) threat and by attuning ourselves to these embodied responses, we can better understand our experience in real time and respond more consciously.
Each of us has a specific threshold for stress and trauma. Stephen Porges, PhD and founder of Polyvagal Theory, describes this threshold as our Window of Tolerance. The wider your window, the greater tolerance you have for stressful events and demanding situations. The narrower your window, the lower tolerance you have for stressful situations and hardship. The width of your window is not fixed, though, and it’s been shown that persistent stress and trauma shrink your window, while safe connection and healing widen your window of tolerance (if you’re a visual learner, check out the image at the end of the article).
When we are within our window of tolerance, we are still susceptible to feelings of stress and discomfort, but our ability to respond is not compromised. We are still within our “comfort zone” for dealing with things. When we are outside of our window of tolerance, however, the part of our brain that we rely on for complex thinking/functioning (i.e. emotional regulation, impulse control, and decision making) goes offline. We default to our mammalian brain, so to speak, and our sympathetic nervous system is activated; here enters Fight or Flight. These are hyperarousal responses, meaning they’re action-oriented and drive us to either gain control through asserting or by escaping. These responses are high energy and require a lot of our bodies. We also have a hypoarousal response that’s driven by the parasympathetic nervous system - meet, Freeze. This response is when we feel overwhelmed by the stress at hand and our bodies shut down, we feel numb, and become frozen in time. It’s believed that this is one of our very first evolutionary adaptations, to become frozen in the presence of true threat, and in Polyvagal Theory it’s attributed to what we now know as the Dorsal Vagus (immobilization).
Our parasympathetic nervous system plays a bigger role in our survival than just freeze, and is also responsible for the cool down effect after you’ve had an episode of fight or flight, and helps bring our bodies down after being wound up. It’s our relaxing system. It is home to what Polyvagal Theory calls the Ventral Vagus - the center for connection or the “smart vagus”. It’s the Ventral Vagus that sets humans apart. We are beings wired for connection, evolved for connection, and it’s through this nerve network that we are able to socially engage and feel safe. When we feel or become isolated and disconnected, we become more susceptible to threat and harm. After all, it’s through community and tribes that humans have learned to survive this world.
So, to review, when the dorsal vagus (immobilization) is activated, the ventral vagus goes offline. When our sympathetic nervous system (mobilization) is activated, the ventral vagus also goes offline. And when the ventral vagus goes offline, our ability to feel safe and connected goes out the window (pun intended).
It’s important to note that the turning on and off of these different response pathways operates outside of the conscious mind; it’s involuntary. What makes this even trickier is that it isn’t just real life threat that drives us into one of our survival modes, but it’s the perception of threat too, which actually may be more related to past memories than current reality. This is what we call a trigger. This is monumental when considering what happens during interpersonal conflict. Relational trauma is one of the most common types of trauma in our modern day world, so it’s no wonder we have quite a few triggers built up from past relationships. This becomes problematic when we consider that the Ventral Vagus, our social connection center, goes offline during times of stress and being triggered. Have you ever found yourself in an unproductive argument with your partner where neither of you can get through to one another? It’s likely more than just stubbornness or ego, but that both parties are without the faculties to find safe connection with one another. Both feel threatened and are on high alert to maintain self-protection.
The good news is that it only takes one person to shift the course of the interaction thanks to co-regulation, the ability to self-regulate through the self-regulation of another person. We feed off of each other’s energy, and it turns out we feed off each other’s calm too. Things like tone of voice, facial expression, body language, spatial proximity, and touch, are all cues we use to assess how we should be responding. So the same way an argument can escalate from one person simply sharpening their tone, it can also de-escalate through softening of tone or facial expression. (Does “it’s not what you said it’s how you said it” sound familiar?) When we have a more regulated system, we search for those safety cues to pull us out of a threat response and help us redirect the conversation in a more productive and loving way. The more familiar and connected we become to our cues of safety, for ourselves and for our partners, we can shift our center for social connection back online more quickly and effortlessly.
Our bodies carry our lived experiences within us each day, interwoven into the neural networks of our nervous system. When we learn to tune into what our bodies are telling us, we can meet our experience with more self-compassion and conscious awareness. Next article, we’ll take a look at how we can build stronger mind-body connections, enhance co-regulation abilities, and widen the window of tolerance.