The Wanderer
Perhaps not unlike those meandering through the streets stopping at one casino and then another, the Vagus nerve in our body has also been called the “wanderer nerve”. Our central nervous system consists of the brain and the spinal cord. Nerves that originate directly from these main structures are called either cranial nerves (arising directly off the brain & brainstem), or spinal nerves (arising from the spinal cord). We have 12 pairs of cranial nerves, the majority of which don’t leave the head and neck. One however, ventures far from the brain and makes its way down the neck and trunk, all the way to our digestive system and internal organs. This nerve is the Vagus Nerve. It is generally a parasympathetic nerve and is involved in the regulation and control of many of our organs, having effects on things like respiratory and heart rate as well as digestion. It is also very good at tattle tailing, with the majority of the fibres dedicated to reporting directly back to the brain information from our thoracic and abdominal organs, and our enteric nervous system - which is a special nervous system that resides in the gut.
As it is a 2-way street, the Vagus nerve is an important player in the link between our gut and brain (aka the gut-brain axis) and as such has been at the centre of research linking our gut health with our mood and inflammatory conditions. Much of our immune system is dependent on our microbiome (the colonization of various different bacteria inside our GI tract) and so our gut health has far reaching effects on the entire body. The Vagus nerve as well as various hormones released from the brain have direct effects on the digestive system, and now we know that via the Vagus nerve, what’s going on inside our gut can also have drastic and fairly direct effects on our brain. Currently, more and more importance is being placed on gut health for those suffering from immune or inflammatory conditions as well as those living with psychiatric conditions. We now know that this nerve that we once thought just wandered around the body, is actually not lost, but providing an intentional link between the brain and our organs.
Doing things that stimulate the parasympathetic system (the rest and digest system), as well as mindfulness based activities and experiencing positive emotions also stimulates the Vagus nerve. In addition to positive social experiences, these activities can include relaxation activities such as focused breathing, yoga, meditation and positive mindset practises (to name just a few). In fact, as reported by Breit et al. (2018), numerous studies have found that yoga based therapies including yoga breathing have a direct effect on vagal tone/vagus nerve activity and can have positive effects on cognition, autonomic regulation, mood, stress coping, and digestive functions. Because of this, vagus nerve stimulation (both medically via electrical impulses as well as activities that promote the function of the vagus nerve) have been used to help those with depression, anxiety, and PTSD. Because of the toxic and damaging effect that prolonged stress has on our body via increased inflammation, the same activities that stimulate our parasympathetic system (and therefore increase vagus nerve activities) have been suggested for those with immune regulation disorders including auto-immune and inflammatory conditions, and particularly those who suffer from inflammatory bowel diseases.
Just to complicate matters further, the “polyvagal theory” has been proposed by Dr. Porges and suggests that the Vagus nerve actually has two components to it, a freeze state (so we’ve gone past the sympathetic fight or flight response and are now “frozen”), and a social engagement side where we feel connected and safe (with ourselves as well as others and our environment). As you can imagine, the state we’d like to spend most of our time in is the social engagement connected state. It is proposed that healthy functioning of the vagus nerve is the control centre for this. This theory is a topic large enough for books in their entirety so this brief explanation doesn’t give it the justice it deserves. But now you know it exists so if you want to delve further you have something to google.
A little Vagus nerve re-set exercise for you developed by Stanley Rosenberg, - if you’re feeling a bit wound up lately. Lie on your back, interlace your fingers behind the back of your head at the base of your skull applying gentle pressure wth your palms. Next, with your hands still there, turn your head slowly to the right and then left. Then, with your head straight and your hands still in the same position, look to the right with your eyes and wait until you sigh, yawn or swallow, then move your eyes to the left and again wait for a reset sign. That’s it! If you are somewhere that you can’t lie on your back, you can also try this just leaning back in your chair, perhaps after the next time your boss or co-workers start to get “on your nerves”.
We’ve only just barely scratched the surface on this nerve, but I think it’s safe to say it is a pretty important one, so here’s to the wanderer!