WARNING: Do not read this if you are going to read half. Do not read this article if you cling to the security of the ground below you because it may crack and then you might have to make a move. [This is a collaborative article between myself and Dr. Ben House (he wrote Part 1, I wrote Part 2 for those keeping score). It gets in the weeds a bit but we are really excited about the potential touched on here!]

Forty miles per hour on a tight left turn, OK 40 kilometers per hour. Nothing between me and rocks but my skin. Up a mountain side and down through a river, twenty minutes of short breathes, tension, and focus. Then I hit the kill switch. Everywhere you look is green and the world stops. I swing my leg off the bike and exhale. This is a microcosm of life. Alternation. Not good. Not bad.

Sympathetic activation is normal.
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You are walking through a dark alley and a man flies out a back door. Your heart rate jumps immediately. Your pupils dilate. You get tense. Your respiration changes. You’re ready to fight or run. That is normal phasic sympathetic response from your vestibular system picking up a fast moving object in your peripheral vision. This has to happen immediately as we can’t have to think about getting ready. It would be too slow to survive. This activation lives in the midbrain all by its lonesome. Same thing with pain. It lights up sympathetics. Survival. Important.
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However, if you get anxiety from sudden noises, flashing lights, someone running by your house, or crowded places that means this autonomic reflexogenic sympathetic area of the midbrain may be firing too hott. You might also see tearing from a pen light or light induced headaches. Or maybe your mom freaks out when you turn the music up and just. can’t. take. it. anymore.

Conversely, if you are in your bed and you think about being in a dark alley and man flying out a back door. Your heart rate jumps immediately. Your pupils dilate. You get tense. Your respiration changes. You’re ready to fight or run. But, you’re in bed and the covers can’t cave you. That is normal phasic sympathetic response initiated by your ventromedial prefrontal cortex. Your thoughts produced an autonomic response. Real or not real?

But sympathetics aren’t all negative. Maybe you think, I have to study for this exam and you fire sympathetic centers and this allows you to focus and concentrate (epi and norepi). Then you calm down after it’s done and your lateral hypothalamus inhibits sympathetic tone. Whew, back to baseline. Chillllll.
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Or you are about to destroy some weight and your sympathetics get all fired up from multiple areas of your brain, your limbic system remembers the gym itself, the smell of it, the writing on the wall, and feels the presence of all your big bad lifting friends putting on their gear and talking smack. Your thoughts and cortex drive sympathetics further. You are pumped, excited to train, and you have been looking forward to this all day.  I might have gotten a little sympathetic shift out of you right there. This shift allows you to divert blood to the working muscles and the brain and allows you to focus and perform. Cortisol in turn amplifies your ability to use substrate, it reduces inflammation, and increases pain tolerance.

Now the key with all of these is that they are phasic and not tonic (constant). We have to inherently be able to shut the sympathetic system down when the stressor disappears and we also have to have the ability to regulate it with our thoughts and actions through our anterior cingulate (think mindfulness and meditation).
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My favorite way to think about this is to watch dogs. A squirrel runs along the railing of our deck and it is pure bedlam until the squirrel scuttles up a cedar tree onto the roof. Then in about 90 seconds they are all napping and smiling again. Dogs don’t have as big of a prefrontal cortex as humans and they are obviously much more limbic. This can get them in trouble. There is a cute female dog. Oh Hi. Very aggressive inappropriate Hi. But it also allows them to not create unneeded stress responses through their thoughts.

This stuff is complicated, but also simple.

Inflammation, oxidative stress, and hypoglycemia all activate sympathetics and feed off each other. For example, you have an anxious patient who works in a crowded office. She is going through a divorce and isn’t sleeping because she can’t slow down her thoughts and isn’t used to sleeping alone. She now has horrible sugar cravings and gets shaky throughout the day. She doesn’t feel like eating and hasn’t touched a vegetable in weeks. She also developed a persistent cough that doesn’t seem to go away. She feels bad about herself so she walks in a CrossFit gym to try to get in shape.

You see the problem?

Let’s keep going.

She loves beating herself up and starts exercising to deal with the pain. This stress further lights up her sympathetics which in turn causes more blood sugar dysregulation. BUT one of her friends told her she should try the ketogenic diet to lose some weight. She loses a couple pounds but her shakiness and sleep are worse than ever. She just can’t seem to control the sugar cravings and gets into a weird disordered eating pattern with donuts and margaritas. This all leads to insulin resistance, less resilience in the face of stress, and lowered immune function because of this excessive stress. Now she catches some kind of virus from being single and ready to mingle. This further activates an immune system that is dysregulated because she isn’t outside and doesn’t get enough vitamin D. The immune system runs off sugar and in turn exacerbates that loop. Now due to the virus and her immune system fighting a chronic infection and her lowered vagal tone, she gets a GI infection, which turns into leaky gut. Then BAM – autoimmune thyroid, depression, and things just got really real.

To fix this we have to be able to see the loops.

These loops are bigger than PRI, bigger than acupuncture, bigger than adaptogens, bigger than any version of the paleo diet, and bigger than your favorite SIBO protocol. Fixing this person involves a comprehensive neurometabolic and immune/autonomic modulating approach.

I took it out a little further but here is as a picture from the Functional Neurology Seminars, which are absolutely amazing and put on by Drs. Brock and Kharrazian. These men will change the world and already have.

​The reach and integration of these concepts is very fun and academic. We have the opportunity to integrate many fields such as: exercise science, physical therapy, nutrigenomics, functional neurology, and functional medicine. But we also have to understand that this human is in a pretty vicious loop and to break this cycle is going to take effort on the part of both the patient and perhaps even multiple practitioners, but none of this works if Suzy Q doesn’t master the fundamental principles of health…and take a deep look at why she hates herself right now.

You thought we were done?

Thoughts on Sympathetics and the Neuromotor System

If Suzy Q is tonically upregulated she will likely be unable to move well into rotation. We tend to sagittalize with chronic stressors as we derive much immediate power from our extensor musculature. However, this reduces the ability to rotate our joints without compensation, which is problematic if you are not in mortal danger and want to, ya know, function like a human.

If sympathetics are fired up then we can’t inhibit tone due to direct innervation of musculature via sympathetic input (Radovanovic et al) and inability to exhale. So many overly sympathetic creatures are unable to exhale fully and pause. Without this capacity, every rapid apical inhale digs us deeper into a sympathetic hole. If you can’t exhale then the vagus nerve is inhibited, digestion and peristalsis are slowed and bowel movements become irregular and you can initiate the slew of consequences Dr. House mentioned above.

Oftentimes we will see plenty of abdominal tension and guarding here, more evidence of a threatened system. Without the vagus nerve, inflammation can become chronic as the feedback loops of the dorsal vagal complex (primary relay station for sensory information from the body to the brain and back) are disrupted and our internal awareness lessens. We become more externally reactive and internally careless. This is probably the start of a lot of intestinal disorders.

If vagal tone is low, it makes it harder for us to pay attention and connect with people as we are in fight/flight/freeze mode. Memory suffers and it’s more difficult to learn and consolidate new skills. All of which are stressful – so stress here is causing more stress. This is a bummer. Our HRV goes down and when variability is lessened our systems are more rigid. Heck, we are even worse at making good decisions and reasoning thru problems (Grossmann et al).

From a mechanical perspective, without the ability to fully exhale can you truly flex the spine? If I’m extending with every inhale and maintaining a hyperinflated state, the neurological state is kept sympathetic. Take a few rapid breaths in with a crummy exhale and see if your own heart rate doesn’t rise. With air still in the chest it becomes difficult to flex around those balloons called lungs and without flexion it is more difficult to allow for adaptive movement thru the extremities. The perceived inability to adapt to the environment only serves to rigidify the system.

So you can see the positive feedback loops in play here.

The ability to shift, or adjust, is critical in building resiliency. A person who is unable to shift is one who is trying to climb the mountain with a single gear. You may get to the top but it’s going to take a lot of energy and resources in so doing. In order for us to change behavior and allow for positive adaptation to occur we must create an environment without compulsion and allow for behavioral options. Someone who is stuck in an upregulated, sympathetic state only digs deeper into that the more they strive to dig out of it – it’s like quick sand. As providers, we need to see where the system is open to change and provide someone another option, a choice.

​This can, and should, be provided by multiple practitioners.
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Psychology, physical therapy and S&C, nutrigenomics, dentistry, optometry all could play a role here in helping to shift Suzy Q back to a regulated autonomic state.  

Negative thoughts and self-image could be driving excessive muscular tension (psychology).

Poor spatial awareness and breathing patterns could be preventing synchronous, coordinated movement.

Maybe she has an SNP that is hindering her ability to clear epi/norepi so she is naturally predisposed to being unable to turn off sympathetic tone as easily.

If she has a malocclusion that is locking up her head (dentistry) or an altered visual system on which she overly relies, perhaps an optometrist could help.

​The point here is that stress is systemic and multifactorial and to combat an emergent problem such as this we need to address all contributing facets. The relative contributions of each are idiosyncratic but the rules governing autonomics are not.

If we aren’t physically fit, maybe our environments are perceived as more threatening than they really are so we become more rigid and tense in an effort to protect us from too much movement that could be dangerous. It’s a perceived mismatch between us (our self-image) and our environmental demands. The bigger the gap between what we need to do and what we think we need to do, the more tension and threat we will perceive.

Real or not real?

Very Real.

– Seth

​Dr. Ben House is a fantastic functional medicine practitioner and exceptional writer and thinker. Reading his work on his website, FunctionalMedicineCostaRica.com, will open your mind to the interconnectedness of all things.