How Mental Illness Affects Your 'Window of Tolerance' (and Why That Matters)

Have you ever experienced a period of extreme sadness or emptiness after having a panic attack? Have you ever been so worked up about something you eventually crashed and didn’t feel like yourself for days or weeks afterward? It’s no secret trauma has a lasting effect on our mental and physical health. Not only can prolonged stress increase the risk of high blood pressure and stroke, it also puts us in a position to develop post-traumatic stress disorder (PTSD), anxiety and mood disorders, as well as other compulsive behaviors — all of which pose serious dangers that can have chronic, long-lasting effects on the body and the psyche that are in ways harder to manage than the prompting event. But what about the foggy stuff that happens to us in between? The stuff that we experience inside our heads that we can’t justify or explain the significance of.

Sometimes, profound stress makes us completely zone out for a while. A lot of people describe this spacey, zombie-like episode as having “brain fog,” which is a perfectly accurate depiction of the sensation because you feel as if your thoughts have been slowed down by a dense cloud. Maybe you have also heard or used the expression, “being down and out” to explain how you’re feeling. As it turns out, being down and out has a scientific and metaphysical explanation.

You see, every human being has an emotional, mental and physical stimulation threshold. This is the level of pain, irritation, anxiety, stress, etc. your body and mind can safely withstand without disrupting your natural emotional state. Life is a series of ups and downs; we experience painful and trying events as well as joyous, life-affirming ones. How we react to the upsetting stuff determines the size of that threshold.

Dr. Dan Siegel describes this as your window of tolerance.

There are endless variables that contribute to the size of your window of tolerance. Some people are bonded to radical acceptance, barely getting overwhelmed or discouraged by the trials and tribulations of their daily lives. Therefore, their threshold is quite wide. Those with a narrow threshold may experience more breakdowns, outbursts of rage and emotional malfunction because they unwittingly allow unpleasant interactions and challenging memories to steep within their subconscious until they become unmanageable. It is at this time when they are pushed out of that frame of things they can tolerate. 

No two people can be held to the same standard of self-regularity because each person has a different threshold of tolerance. As you may have learned about mental health diagnoses, siblings can grow up in the same household experiencing the same events as one another, but assimilate them completely differently.  Hormones, temperament, personality, exposure and experience are all elements that affect our coping skills. Sometimes our ability to manage stress differs because of temporary circumstances in our lives that are out of our control while other factors are more concrete and harder to change within ourselves.

When you leave your window of tolerance, a number of things can happen. Think about a time in your life when you’ve become overwhelmed by a situation. Did you take a step back until you could reapproach with a clear mind? Did you feel like you had no choice but to retreat to your safe place and close up for a while? Did the distress make you angry and want to yell at everyone involved? Maybe you’ve done all three at some point. The main concern with being overwhelmed is you’re feeling too much all at once and your nervous system becomes overloaded with stimuli. Your brain then reacts by putting you in “fight-or-flight” mode, or it shuts down altogether or both — one after the other. These “modes” or states of mind are called hyperarousal and hypoarousal, and they kick in when you’ve breached your stimulation threshold and left your window of tolerance.

I first heard the set of terms in my therapist’s office, and I have to admit I was a little embarrassed when my doctor started referring to me as being “aroused;” I thought she was way out of bounds. There’s a mood irregularity I haven’t been able to easily describe or label since my journey with borderline personality disorder (BPD), PTSD and major depressive disorder began when I was only a child. All I knew was, from time to time, my emotions would become so strong it would take me out for a couple days. I would say to myself, “Well, you felt too much again and now you’re going to pay for it.”

Her description of what I was experiencing followed a story I had shared with her about how a run-in with an especially tense and anxious situation led me to be indescribably irritable, exhausted and downright nasty for weeks after the incident took place. This happens to me all the time. For years I described myself as being an overly sensitive and emotional person who had consistent, unjustifiable mood swings that came out of nowhere. I couldn’t understand why I was so moody all the time for what seemed like no reason at all. People loved to label me as “angry.” I can’t count the number of times I’ve been told, “all I want to do is fight,” which deep down wasn’t true at all, but the behavior fit the bill. I couldn’t stop myself from lashing out at the people closest to me. This is a prevailing symptom among people with BPD, but it can actually happen to any and all people once they’ve left their window of tolerance.

The problem I was having with my unsteady disposition was due to the degree of emotional trauma I had experienced that had dwindled my tolerance away until it was next to nothing by the time I reached adolescence. I was a walking exposed nerve. You don’t have to be depressed or diagnosed with a mental illness to have emotions that don’t necessarily match the situation. It took me years to recognize this pattern, I’m talking decades.

Understanding hyperarousal and hypoarousal. 

Hyperarousal is when your emotions go up, up, up to an unmanageable level of stimulation. Think of yourself as a pot of water on the stove; when the heat goes up, the water starts to become agitated. When the threshold of your tolerance has been exceeded, you may lose your sense of serenity and stillness and begin to boil and spill over. The characteristics of hyperarousal are similar to those having an anxiety or panic attack. You may experience an increase of sensitivity to your surroundings (hypervigilance), a spike in irritability or hostility, trouble sleeping or concentrating and an inability to settle down or level back out. You may relate to this stage when you’re feeling out of control of yourself. At times, the intensity and rapid onset of these overwhelming emotions feels unjustified and irrational. The more you try to suppress them and they don’t subside, the angrier, more afraid and out of control you feel. It is in this stage people are more likely to engage in reckless, impulsive behaviors or give into their addictions.

Eventually, that pot of boiling water is going to boil and steam away until nothing is left inside. This is hypoarousal. It happens when you dip down to the dark layers beneath your window of tolerance. It can follow a traumatic event or, more often, after a stint in hyperarousal. If our bodies experience overstimulation for too long, the natural order of things is to crash and burn. It’s in this stage where the disassociation and numbness set in. Extreme fatigue and lethargy, a feeling of being dead inside or feeling nothing at all, depression and being spaced-out are all things you can experience when you’ve entered hypoarousal. Your memory can also be affected. You may find yourself struggling to recall facts or memories as well as forgetting events that happened to you during hyperarousal or hypoarousal once you leave this state. 

There are overlapping symptoms in either of these emotional states. Some people may feel rage in hypoarousal or be zoned out in hyperarousal. The commonality in both aroused states is your emotions have taken over, you have very little control and you’re undoubtedly uncomfortable. Lack of concentration, for example, is a component that becomes compromised during either hypoarousal or hyperarousal. You may not be able to focus enough to complete a task, read a book or even a just a passage of literature, sit down to watch a 30-minute episode of your favorite show or even write about your experience in a journal.

In my own experience, I feel as if my natural state is hypoarousal. I’m a master of a convincing autopilot mode. Though I don’t always feel depressed, I find it nearly impossible to stay mindful (in the present moment). There are times when I arrive somewhere and have no recollection of how I got there at all. I can very rarely find the words to properly communicate what I’m trying to say. I sort of just float through each passing day until the rare occasion arises when I feel completely in control of myself and my environment. Spacey is my forte. I also can’t think for myself, which is probably the most frustrating side effect of all. Making simple decisions like which socks to put on, what I want to eat for lunch or whether I should pick up the phone when it rings or not is a mentally impossible and daunting task, it’s as if there’s a physical barrier inside my brain restricting any and all cognitive skills from getting to my frontal cortex. I need someone to literally tell me what to do, as well as how to feel and react to things. The entire premise of past experiences and lessons learned, common sense and other factors that influence decision-making seemingly lose their value until I return to a balanced frame of mind. I become an empty vessel, lost at sea, looking to passersby with child’s eyes in hopes someone will take responsibility for me until I get home.

It can take weeks to return back to a balanced state after becoming stuck in hyperarousal or hypoarousal. Remember the pot on the stove? It takes a while for that boiling water to cool back down again. You also can’t expect the pot to magically replenish itself with a comforting level of lukewarm water after it becomes bone-dry. The emotional whiplash caused by these mood shifts is devastatingly draining. This is a difficult roller coaster to be on. The idea is to broaden your window of tolerance so you can manage more situations and experience fewer crises. If we cannot take the reins and steer our emotions when we’re in distress, we can work toward coping more effectively when things do go wrong or upset us. Do this by practicing radical acceptance of the things that go on around you. You can also get help from a counselor or health care provider who will teach you the skills you need to remain in balance when challenging situations arise.

There is surprisingly little information online about the window of tolerance (even on The Mighty!). I hope I’ve helped shed some light on this topic and provided you with a level of clarity or relief for your concerns.

 For more information, check out this article on NICABM.