What happens in Vagus

17/05/2020

"What happens in Vagus"

Everywhere you look in Ireland there are those yellow, black and white ads with spiky sphere graphics representing viruses. I was having a nice relationship with the colour yellow until they authorities hijacked it. Now, I'm not so sure. I'm a visual learner, so as went into the eighth week of lockdown and crisis fatigue began to set in, I found the UK authority's messaging began winning my attention instead. They changed their slogan from 'Stay Home' to 'Stay Alert', as they gradually attempt to tiptoe back towards normality. In the manner of a thermometer, they've also unveiled a colour coded visual scale that will allow them to communicate whether the perceived safety level will permit social engagement or require a retreat back to the safety of the home.

Once the brief burst of novelty subsided, I found it didn't sit very well with me. The visual thermometer-type scale where blue is safety and red is danger seems to me to not only illustrate, but also potentially ramp up the all-too-familiar stress response that has become chronic in the modern world. I wonder in the weeks and months to come whether this blue to red spectrum will act like a light does for moths, and entice an already teetering tendency for anxiety to charge towards the heat of panic, leaving people repeatedly banging their heads against the glass of the 'worst-case-scenario'. Surely there's enough prolonged, prevalent, insidious stress in the air without lighting a neon meter to guide us?

Sorry. I only imagined the neon, and the light. Fear can play funny tricks in these are strange, strange days. Once I'd drawn a few slow breaths, it occurred to me that a useful way of understanding the UK information campaign, specifically, the move from 'Stay Home' to 'Stay Alert' is to see it as a collective expression of two elements in the Polyvagal Theory. This model explains the mechanics underlying our individual responses to challenging situations, and, as such could be a useful means of thinking through our collective reactions. In this model (developed by neuroscientist Stephen Porges), our vagus nerve enables us to switch between three possible reactions. We can engage in protective immobilization (the 'freeze' response), highly alert mobilisation (the 'fight or flight' response) or we can stay calm and engage in the connected 'social engagement' response.

The 'Stay Home' message during this lockdown stage could be read as a collective opting for the freeze response (I wrote about aspects of this in an earlier blog post). On an individual level immobilization triggers primitive fear reactions stored in the oldest part of our brain, and is characterised by (among other things), disassociation, withdrawl, depression, numbness, and defensiveness. Not surprisingly, it's a state that isn't condusive to problem solving, since thinking patterns slow to a halt.

If 'Stay Alert' is the prescription for the immediate to medium term future, it points towards a collective 'fight or flight' state. Individually this is not a pleasant place to be. Sympathetic nervous system activation involves a cascade of physical, emotional and cognitive disruptions including increased heart rate, blood pressure, hyper-vigilance, anxiety, a perception of danger, heightened sensations, rigid thinking, poor judgement, racing thoughts, and obsessive behaviours. The limbic brain, evolutionarily the second oldest part of the brain takes control and behaviour is characterised by emotional reactivity. Imagine collective fight or flight? Some turbulence would be expected. Perhaps we'd need to buckle those seat belts!

Thankfully, we have other nervous-system response options, and our most evolved one finds us less ruffled, and able to see options, solve problems and make social connections. It's described in Polyvagal Theory as 'social engagement'. Physical and emotional processes regulate, and the thinking mind can take the reins from the unconscious processes of the autonomic nervous system. The Bodymind[i] functions optimally and we gain greater access to the pre-frontal cortex (the most recently evolved part of the brain), where intuition, insight, awareness and coherence become available. The ears open and the face smiles to lubricate social communication. 'Social engagement' is the place we want to be most of the time.

Although we are each of us only one ant in a much bigger collective anthill, I find it's helpful to be aware of, to recognise and understand these various responses as they unfold individually and collectively. Understanding the agency we each have to stay calm, open, observant and learning is the key to keeping our eyes on the prize of the collective, connected, social engagement we all so keenly miss, and dearly long for at this time.

Anyway, I think it's time I formally introduced the Vagus Nerve. (I think it deserves the capital letters.) The Nobel award winning Otto Loewi discovered it in 1921.[ii] As many of my yoga clients know only too well, I talk a lot about the Vagus Nerve while I teach. Since the 'gospels according to Maria' are typically preached in the brief junctions between asana, the opportunities for biological explanation are short. In the snippets available, I tend to reach for the shorthand that this important nerve is the 'gearbox' between one's various nervous system states. The shorthand continues that keeping this 'gearbox' well maintained means you will have improved agency when it comes to self-regulation and resilience.

Since I can't expand beyond snippets in class, my interest in mental health draws me to focus on nervous system states, and in particular how they affect behaviour, emotional regulation, cognitive processing and resilience. Poly Vagal theory is a useful tool for investigating the subject when one's interest is in the nervous system, but it's important to point out that this is just the tip of the proverbial iceberg. When it comes to the Vagus Nerve, explaining anything fully might need a series of books rather than a blog post.

Here, I'll squeeze what I can into this one paragraph. This longest cranial nerve is one of the main communication channels between the body and brain and it wanders throughout upper body and torso, relaying status updates from all the major organs. Disorders of the Vagus can manifest for example, as problems with healing and also learning. Its plays a hugely important role in inflammation, (which goes hand-in-hand with pain and usually indicates of the course of disease in the body). A huge proportion of vagal fibres enervate the gut, making it the 'wiring' behind 'gut feelings'.[iii] One's vagal tone (the measure of whether or not it is functioning properly), impacts, among other things one's general health, heart rate variability, growth, immunity and glandular activity as well as glucose, blood-pressure and stress levels. I could go on, but I promised just a paragraph.

Evolution leaves us with two versions of it - the older (dorsal) branch that runs to the stomach, liver, gall-bladder, spleen etc., (below the diaphragm) and the newer (ventral) branch that regulates heart, lungs, pharynx, face etc. (above the diaphragm). In my very simplified understanding, these two branches of the nerve give us access to two sets of 'positive/negative' possibilities.[iv] On the 'positive' side, the older (dorsal) side allows for rest, digest, restore and reproduction responses, while on the 'negative' side it triggers the freeze reaction. The newer (ventral) branch is involved in the 'negative' fight or flight reaction, while on the 'positive' side, social engagement behaviours emerge.

Our Autonomic Nervous System (ANS) has two primary divisions, the Sympathetic (SNS) and Parasympathetic (PNS). The older vagal branch is associated with the PNS and the newer vagal branch is associated with the SNS. As you breathe in, the heart speeds up and the sympathetic side activates just a little, while breaths out slow down the heart and activate the parasympathetic side just a little. Imbalances accrue over time and can become entrenched. For example fast breathing that has high in-breath lengths, and low out-breath ratios can lead to anxiety patterns and panicky feelings. This brings me back to my 'gearbox 'analogy. If vagal tone is poor it is difficult to shift gear away from an uncomfortable setting and choose another option. (I will signpost some yoga practices that can help with vagal maintenance at the end.)

A well-functioning Vagus Nerve helps you to manage the delicate balance between the sympathetic and parasympathetic nervous systems. Porges talks about an optimal 'Window of Tolerance' emerging once this balance is achieved, where the 'positive' aspects of both systems blossom into a beautiful homeostasis. Feelings of safety and calm allow both the restorative 'rest and digest' and the 'socially engagement' response to happen. Let's call this place 'OM'.

Porges' theory (1994) is a relatively 'new kid on the block' but its created huge impact in the scientific community for its ability to help explain complex problems like PTSD and Autism, where, for example, disassociating dorsal vagal responses can take over and disallow access to social engagement and homeostasis. Like so many things that emerge as breakthroughs in Western thought and modern science however, the Eastern ancients had a handle on the concept eons earlier. The theory is something akin to Yoga philosophy's 'Gunas' long ago described in the ancient Bhagavad Gita and the Yoga Sutras of Patanjali. I won't be able to do justice to this nuanced, sophisticated and ancient theory here, and a dedicated post would be needed to even attempt it, but I might hazard a sketch from the broadest of strokes. (Comprehensive article here.)

'Rajas' describes a state of activated energy, motivation and creativity that can also bring turbulence and pain. This could be lined up with the ventral branch of the Vagus, and its associated sympathetic nervous system. The 'nutshell' version of 'Tamas' involves the qualities of stillness, stability and restraint but also inertia and indifference, which bears some resemblance to the dorsal vagal characteristics and the parasympathetic response. What Porges calls the 'Window of Tolerance' (the place I playfully called 'OM' earlier), where the perfect balance between the older and newer vagal responses is found, seems to resemble the yogic idea of 'Sattva'. This describes a quality of pleasure, peace and clarity, where lucidity and inspiration can emerge.

Both Buddhist and Yogic traditions were long ago aware of the opportunity to find balance moment by moment, through the breath. Both traditions also have a long history of chanting, and it turns out that the Vagus Nerve has a special relationship with the vocal chords. The nerve is most exposed in the neck, so the rustle in the throat caused by the Ujjayi breath and asana that open or constrict the neck such as Fish Pose and Shoulder Stand are means to stimulate and tone the Vagus, as are Bridge Pose and Legs up the Wall. Twisting poses access the torso and also exploit the nerve's abundant visceral innervation. Newer modalities are also emerging that are harnessing the power of the Vagus Nerve to bring healing. Here, I must mention Craniosacral Therapy and in particular the easy-to-learn release techniques taught by Stanley Rosenberg that I often feature in my yoga classes. (See his book, 'Accessing the Healing Power of the Vagus Nerve').

In a future post I hope to continue building on the story of the amazing Vagus Nerve, in particular, looking at ways that good vagal tone can help access the Window of Tolerance/ Sattva /'OM' type states discussed above. I feel this place bears abundant resemblance to the positive psychology 'Flow' state proposed by Mihaly Csikszentmihalyi, where optimal states allow a platform for positive risk-taking behaviours to emerge, as well as a high level of productivity, creativity and innovation.

In the meantime, let me prompt you to make better friends with your Vagus Nerve by combining the two most simple ways of activating its 'positive aspects', these being to merely take some long, slow, diaphragmatic breaths and let your face lift towards a smile!

(Be sure to explore the practices and information on the links below.)

Bridge Pose (Setu Bandha Sarvangasana ) (Benefits of the pose explained by Kathleen Bryant, of yogabasics.com)
Chanting explained by Sadhguru.
Rosenberg's Basic Technique

[i] I'm tipping the terminology hat here to the wonderful Candace Pert. See for example this brilliant scientist's book 'Molecules of Emotion'

[ii] A neurotransmitter secreted by the vagus nerve was also identified at the time and called 'Vagusstoff'. Today it's called acetylcholine and its understood as being essential for regulating life-and-death type things like breathing and inflammation, as well as day-to-day things like learning and memory.

[iii] A Swiss study done involving snipping the branch of the vagus nerve that enervates the gut, using poor, unfortunate lab rats, proves that not having access to their gut feedback and it visceral intuitions left them locked in learned fear responses, long after the environment was made safe.

[iv] This simple reading is low on nuance but it's important to point out that 'positive/negative' assignment has a bias towards feelings of comfort. Panic, for example, gets you mobilized and away from an attacking bear, which is very positive. I'm using shorthand and calling it 'negative' purely because it doesn't feel nice.