Your Nervous System, Polyvagal Theory and Yoga.

Sep 29

You have probably heard about the calming effects that a Yoga practice can have on your nervous system, perhaps hearing phrases such as ‘fight-or-flight’ or ‘rest-and-digest’ in the context of the calming down, or even in the Yoga Shala. If you have done Yoga, ( I make no assumtions here), you’ve almost certainly experienced first-hand the flush of feel-good, calming endorphins when you practice Asana, Breath or Meditation. Today I want to unpick these processes and terms relative to the stress-calm continuum, highlight the undeniable importance of a regulated nervous system for health and longevity and of course begin to skim the surface of how these vast and nuanced subjects intersect with the practice of Yoga. There will be some juicy anatomy moments (can I get a hell yeah from my fellow nerds in the back?!) so stick with it and take this in bite-size chunks if necessary. The nervous system is complex and although I have done my best to simplify its functions, It is also worth noting I am a very keen student and not an expert. So there will be holes in my knowledge and maybe even misunderstandings. I have done my best to share what I understand and hope that this encourages you to do your own further research into this fascinating subject - there are plenty of citations below.

Shall we then?

First things first, we need to understand a little about the Nervous System, specifically the Autonomic Nervous System (ANS) to create a solid foundation before we dig deeper.

“The autonomic nervous system regulates the internal physiological processes we don’t consciously think about (e.g. respiration, cardiac regulation and reflexes). Divided into the sympathetic nervous system (‘fight or flight’) and parasympathetic nervous system (‘rest and digest’), this system maintains homeostasis within the body and does a good job of keeping us alive and functioning.” - Eugene Kwok

The ANS is essentially in charge of the automatic functions of the animal body and up until fairly recently, it was thought that we had no control over our ANS and that its functions were automatic and unreachable through intentional action. As you can probably guess by my tone, it has been proven by wellness mavericks such as Wim Hof and his band of chilly mates, that this is in fact untrue, but more on that later.

These two distinct functional types can also be referred to as Mobilization, which is fight-flight-or-freeze (but actually it is more complex than that) and Social and Safe which is rest-and-digest (again, over simplified). Us Mammals have evolved to be social creatures and have therefore developed these systems to help us engage with the world around us and connect to other creatures. Mammals, generally, need a pack, a tribe, a family to survive and thrive. This ability to engage and connect would have kept us safe in our nomadic lifestyles and actually still does today. Bundles of data, information gleaned via our senses, the things we see, hear or smell, even subtle facial changes or shifts in body language from those we are around, travel from the outside world via the Nervous System and our body responds. The endocrine system releases varying levels of stress hormones such as Cortisol or Adrenalin to respond to threat or a need for mobilisation or feel-good hormones such as Dopamine and Serotonin respond to signals of safety. Essentially our senses and our nervous system is the interface we use to understand how to react and respond to the world around us.

In 1994 Polyvagal Theory (PVT) was proposed by Dr Stephen Porges, professor of psychiatry at the University of North Carolina. Amongst some observations, PVT proposed that the above states are not absolutes, that each system has its own branches and that we operate in blends of them. For example, we have a social state called Ventral Vagal Social Engagement, which is one branch of the parasympathetic system and this is one of the most ideal states to be in as it makes us available to connection, flow, play and mating. This state evolved in mammals to allow us to co-regulate which is the neuroceptive activity of our nervous system matching the state of those around us. Whilst Ventral Vagal is referred to as part of the Parasympathetic nervous system, PVT researcher Deb Dana argues that Social Engagement can also require small amounts of Sympathetic activity; A smidge of mobilization so we can be active participants in our social lives and interactions. PVT also observes that when we feel safe we are available to the world, we see the bright side of situations and find it far easier to assume the best - essentially we are not looking for danger, but for opportunities for positive connection, joy and a sense of presence. When we are in Mobilization, the world appears more threatening and we have our eyes peeled for opportunities for danger. We literally perceive the world as a more dangerous and potentially negative space. Our ears are attuned to lower frequency sounds (like the growling of an animal), faces can look aggressive when they are not and we can be hyper-sensitive to perceiving physical pain. We react by operating from a state of defence.

To understand Polyvagal Theory further, we need some knowledge of the Vagus nerve, named such from the Latin Vagor meaning to wander. Why Polyvagal? Poly means many and vagal from the name of the nerve to which it refers. The Vagus Nerve is the tenth and longest Cranial Nerve in mammals, wandering from the brain through many vital areas of the body including the ears, heart, lungs, gut and viscera. It “is the autobahn between what scientists have referred to as the two brains — the one in your head and the other in your gastrointestinal tract.” - Emily Gersema. Electrical impulses of safety or threat travel from the body to the brain stem via the Vagus nerve, resulting in which state of calm or stress we find ourselves in. It is not unreasonable to think that the Vagus nerve may be the reason we feel ‘guts instincts’. Signals of threat or safety, mild or extreme, zip along the Vagus nerve, bypassing the thinking mind, via our internal organs. Thus we feel physical sensations in our gut or heart in reaction to literally anything that triggers us. Our younger brother jumping out on us, a smell that reminds us of a loved one, the look of someone’s face or the way another human pronounces their vowel sounds. Anything can trigger this reaction and though the intersection of trauma response and PVT is fascinating it is a tangent we will avoid for today.

Let’s get back to Polyvagal Theory and the importance of the third, and yet to be mentioned, state of the ANS.

“According to polyvagal theory, shifts in the autonomic nervous system produces three elementary states: rest-and-digest (social and safe), fight-or-flight (mobilisation) or shutdown (immobilisation).”

Shutdown is ultimately Playing Possum and is the oldest evolutionary branch of the ANS, evolving around 500 million years ago. Shutdown can happen as a response to immediate danger, think of a limp mouse held in a cat's jowls or someone fainting. It can also occur as a cap when our system becomes overwhelmed by fight-or-flight. Basic terms? Burnout.

Most adults have been so busy, so “on-the-go”, so constantly Mobilized that at some point burn out strikes. Modern humans tend to spend a huge amount of time in a state of mobilisation, stress hormones coursing through our systems as we navigate the modern world. We simply did not evolve to manage the amount of stress we contend with. As a result, we get worse and worse at regulating ourselves and end up suffering, mentally, physically and emotionally. If you have been burnt out, you know how little you are able to do, how it can affect not only your physical body and energy levels but also how you perceive the world. When we do not feel safe, everything becomes threatening and when in shutdown, we feel unable to deal with the perceived threat at hand and this translates to how we interact with our fellow humans and ourselves. So why does this shutdown happen as a response to hyper-mobilization?

Our nervous system caps this over-stress as a protection mechanism because high levels of continuous stress are incredibly harmful to our health. If we spend very little time within rest-and-digest how can our body function at its optimum? The simple answer is that it cannot. If we are constantly firing adrenaline through our bloodstream, how can we rest? With huge difficulty or in-effectively, as we cannot heal or engage basic immune function due to being in the wrong state. Being in a state of hyper-mobilization also makes us unavailable to our social state, meaning we cannot connect fully with our loved ones either. We can see that for mammals, over-mobilization is a detrimental place to be and that is without even beginning to highlight the links between cardiovascular conditions, cancers, hypertension and stress.

This is where Yoga enters centre-stage. As we know, Yoga as a system for living champions the practice of Pranayama (breathwork) and meditation. Both of these have been linked to resilience and longevity. A recent study at the Chopra Centre even discovered that a regular meditation practice essentially (and I’m hugely oversimplifying this for the word count) makes your DNA younger by lengthening telomeres. Navy Seals even use Pranayama to prepare for high-stress situations and to manage the aftermath of experiencing them. Yoga practitioners such as Max Strom stress the importance of getting our breath in check, alongside stats from the Stamford Research Institute that predicted depression and anxiety to be the number one ailment in the US by 2020s and as we know, Yoga Pranayama helps with both stress management and reduction.

Breath is an incredible tool for regulation, ancient Yogis knew this as do modern practitioners and now scientific findings support breathing techniques as being triggers for both states of Sympathetic and Parasympathetic Systems. We know that when we are stressed, for example, we breathe faster, or even hyperventilate. Our inhales speed up our heartbeat which stimulates our Sympathetic Nervous system. We get muscular, adrenaline released by the endocrine system and before you know it, we’re firing on all cylinders. In contrast, when we sleep our breathing slows right down, our exhales extend and the Parasympathetic Nervous System engages. Our breath not only signifies what state we are in, it triggers it too.

One example of breathwork that up-regulates the system, is a practice very similar to the Ancient Tibetan Tummo. It has become incredibly popular in recent years due to its use in the Wim Hof Method. This Pranayama is pretty simple, the participant lies down and then increases the pace of inhales and exhales. If you have ever followed along to one of Wim’s videos, his Scandi-God like voice instructs the inhale with a verbose “Fully in!” followed by a calmer, “Let it go.” These large gulps of air and easy exhales, tip the scales of o2 and Co2 in the bloodstream and voluntarily stimulate the Sympathetic Nervous System. This is what is called up-regulation in Polyvagal theory, assuming the participant is in a state of Parasympathesis before partaking in the exercise. You might think that this cannot be a good thing, stimulating an already over-used state, and whilst we have no long term modern studies on the Wim Hof method or Tummo, it does seem to be an incredible resource to create heat in the body (Wim is known as the Ice Man due to feats like running a barefoot half marathon above the Arctic Circle) whilst also hacking the ANS to fight off illness. Read the study if you do not believe me, it is pretty exceptional stuff.

All this just by hacking something that we thought until recently we had no control over. Kind of unbelievable, a little spooky and definitely very cool.

Before I wrap this up, it is important to note that no one state is better than the other, they are simply appropriate or not depending on the context we are in. “The goal is not to always inhabit Ventral Vagal (social and safe)” - Deb Dana. The goal is to have a healthy and functioning nervous system that keeps us thriving and alive. By viewing the nervous system as a function of the body which keeps us alive, befriending it rather than guilting ourselves for its reactions to the world around us we can begin to understand our states, what triggers them to change and what we need to do to regulate them when poorly matched to our surroundings. Whether that is up-regulating up from shutdown, or taking us down from over-mobilization, generally the goal is to harmonize the Nervous System and bring us back to an appropriate state, which in the modern world is often an open, joyful state of Social Engagement - unless of course, you need to run from imminent danger or that forever dreamt of boxing-match with Mike Tyson is finally a reality!

Below I have shared some of my favourite ways to both up and down-regulate the nervous system, from Pranayama practice to woodland walks to listening to your favourite podcast - there is something for everyone.

1. Exhale slowly.

In Yoga, often we put all our attention on the inhale, however recent studies by Stephen Porges observe that a natural inhale followed by a longer slower exhale signals feelings of safety and encourages a Parasympathetic response. Participants even recorded perceiving the faces they saw during the exercise, as becoming more friendly and amicable, a sign of being in the social and safe state of what Dr Porges has coined Ventral Vagal Social Engagement.

2. Listen to an Audiobook or Podcast.

Humans are inherently social and the sound of well-intentioned voices signals safety to our nervous systems. So by listening to audio narrated by a voice that is calm and melodic, we can regulate the system away from Shutdown responses as well as high Mobilisation ie stress! A perfect option for those of us who need recharging with social engagement but sometimes lack the energy for a two way conversation.

3. Have a cuddle.

“When you cuddle with someone you care about, your body releases a hormone called oxytocin that calms you and makes you more likely to deal better with stress.” (Gabriela Pichardo, MD ) No one around? Having a snuggle with a pet you love can have a similar effect or skip to practice number five!

4. Practice intuitive movement.

When we move our bodies in a way that is led by our own needs and desires, we engage intentionally in autonomy. This empowers us and our systems to understand that we are in control of ourselves and therefore safe to lean into our emotions and the present moment.

5. Self massage and Vagus Nerve stimulation.

Giving yourself gentle and loving touch to areas such as the arms, face and hands can help you to feel more embodied in moments when the mind begins to race. Embodiment is when we are in our bodies, experiencing the emotions sensationally rather than getting lost in our heads which can result in disassociating from our body. Massaging specific areas of the body where there is a high concentration of Vagal Nerve branches can also be a useful way to regulate your ANS. The belly, lungs, ears, face and neck are all options. Be sure to take your time, give attention to just one or two areas at a time to down-regulate your system.

6. Get into Nature.

Always a goodie! Nature is generally a reliable source of Nervous System Regulation. The colour green has actually been proven to create calm in the body by being the least strenuous colour for our eyes and brains to perceive. Being in nature without the distractions of technology is also a wonderful way to let the brain calm. Less busy stuff clogging up your thoughts is a sure-fire way to down-regulate. Couple being in the Great Outdoors with some slow, steady exhales and a nervous system you feel fab around and you’re on for a winner.

7. Cold Water Therapy.

Getting into cold water can be especially effective if you are feeling a little flat or unable to motivate yourself. This experiencing of inertia is the Dorsal Vagal Shutdown mentioned above with a hint of activity in the Parasympathetic Nervous system. Getting into cold water essentially shocks the system out of this state. Stress hormones are released in response which, in this case, is a good thing because that adrenal response mobilizes the system and leaves you feeling invigorated. Be sure to wet your face, armpits and neck for the best effects. Added bonus? Go for a dunk in the sea or a lake with people you feel safe and inspired by. You will be more likely to feel supported and build up all-important resilience!

Resources

Web pages

https://www.rhythmofregulation.com/ - Deb Dana’s Website

https://www.stephenporges.com/ - Stephen Porges’ Website

https://news.usc.edu/144479/vagus-nerve-research-gut-instinct-may-have-been-gps-of-early-humans/

https://www.futuremindslab.com/blog/2019/5/2/mastering-the-mind-and-body-conscious-control-of-the-autonomic-nervous-system

https://themovementparadigm.com/how-to-map-your-own-nervous-sytem-the-polyvagal-theory/

https://www.wimhofmethod.com/iceman-wim-hof

https://adaa.org/understanding-anxiety/facts-statistics

https://choprafoundation.org/articles/the-new-old-age-just-got-better/

https://www.nature.com/articles/s41598-020-61241-6

https://rana.medium.com/the-polyvagal-theory-f68fb621ed82