Part 1 of 4: The Wanderer – A Brief Introduction to the Vagus Nerve (our Hero).
This is the first of a series of blog posts on the new rock star of the alternative healing world – the Vagus Nerve.
This post will provide a very brief overview of the physiology. There is oodles on the web if you want to dig deeper. Warning: you may get lost for several years and return more confused than when you left. I quit and poured a strong drink recently when measuring techniques starting talking about integration with chaos theory.
As this is the foundation blog for more practical (and perhaps more interesting stuff) to come – I will cover just enough to support you on the journey though the coming blogs.
WARNING there will still be scary words and crazy science ideas.
Future blogs will cover:
- Part Two: How to improve the health of your Vagus Nerve – based on scientific evidence.
- Part Three: Vagus nerve stimulation; can you really ‘gag’ your way to good health?
- Part Four: Do try this at home; monitoring your own vagus nerve health using the variability in your heart rate.
So let us meet the vagus nerve ….
The vagus nerve, also known as the tenth cranial nerve, is the longest of the cranial nerves. It connects your brain-stem to many of your major bits i.e. heart, lungs, stomach, pancreas, small intestines, gall bladder. It also connects to the muscles in your throat and neck
The word vagus means ‘wandering’ in Latin: an appropriate name, as the vagus nerve literally wanders throughout your body.
Some neat images might help make sense of this in relation to other cranial nerves etc.
This super nerve relays important messages between your brain and organs and influences everything from your blood pressure, digestion and heart rate to aspects of your speech, head movement and breathing. No wonder it’s a bit of a rock star.
WARNING ACRONYMS UP AHEAD
The vagus nerve is the major part of the Parasympathetic Nervous System (PNS). The PNS makes up one part of the Autonomic Nervous System (ANS), the other side being the Sympathetic Nervous System (SNS). The ANS manages your subconscious bodily functions (those you don’t need to think about). You might think of it as a break and accelerator … with the SNS speeding you up, increasing blood pressure, raising heart rate, slowing digestion and the PNS slowing you down by doing the opposite. Hence them being called the ‘fight and flight’ and ‘rest and digest’ (or feed and breed) respectively.
Just as with a car … the accelerator and break need to be well balanced, used appropriately for optimal driving (not to mention survival!!)…as the driver changes from fast to slow to meet the road conditions so should your body to respond to the ever changing demands of your day to day life.
Modern Stresses and the Vagus Nerve
In our modern stressful lives the ‘fight and flight’ has become the bad guy (it surely has within my body). However accelerators in cars are not bad, are they? They are just bad when the driver forgets about or can’t use the break. The problem is not that we have a ‘fight and flight’ it is that it gets stuck on for too long with detrimental (and potentially fatal) effects to our health and wellbeing. If you have had the displeasure of driving in New Zealand or Australia (especially if you are English) you will know what happens when these things are all out of balance.
Where the SNS has become the accidental villain, the opposite is true for the Vagus Nerve which has become the hero, the potential saviour, for those of us stressed out, run down and sick. But as we see, even in this quick overview, none of these guys act alone. None of them are all good or all bad. My mother argues that is true for everyone, all that wisdom must be why her vagal tone is so good.
True story; wisdom has been recently linked to vagal tone (Grossmann, Sahdra, & Ciarrochi, 2016). Well only for those people who were not all up their own …. you-know-what … (but I digress even if it is funny).
Perhaps the Vagus Nerve has become so fashionable (first in research and now on the web) because it is pretty neat and huge and crucial to your health and wellbeing, but so is our heart ….right?
The Heart of the Matter
Interestingly our hero has a fascinating and complex relationship with our heart.
A well balanced ANS (one with what is called good ‘vagal tone’) with the ‘fight and flight’ and ‘rest and digest’ playing nicely together … should result in our heart rate increasing ever so slightly as we breathe in and slowing ever so slightly as we breathe out. If you pay close attention with a good heart rate monitor you will observe this (no your fitbit won’t be responsive enough, for which they are being sued …. nice).
This is a little surprising is it not? Nooo … not major corporations being sued for misrepresenting their products ….. I mean that more heart rate variability is better. Good heart rate variability (or vagal tone) has been linked to a host of mental and physical benefits (other than wisdom).
There will be more on heart rate variability in upcoming posts. For now I want to talk a little about the vagus nerves impact on our social and emotional lives.
Social Support Matters
It is argued the reach of the vagus nerve up into our throat and face has profound effects on our relationships and sense of social connection. Even freakier; it may influence micro or subconscious expressions, within our face and voice. These send powerful messages to others; if the PNS (supported by the vagus nerve) is dominant (when it should be) you are more likely to send positive messages to others.
If the vagus is not working well and you are stuck unnecessarily in the freeze or fight and flight, you may miss such opportunities. I mention freeze as it is another of those stress responses that hark back to being chased by a sabre tooth tiger …. “maybe he won’t see me if I stand very still… please god”.
So those lucky enough (or motivated enough through hard work and lifestyle) to have stronger activity in their vagus nerve are going to have more ‘in tune’ type experiences with others. This is supported in research showing young people with high vagal tone are more valued as friends (Young, 2013). Conversely Pittig, Arch, Lam, and Craske (2013) showed diminished vagal response in those with social anxiety.
The work of Kok et al. (2013) goes further still and proposes a an upward spiral (like a virtuous circle) where better vagal tone creates more positive emotions, which creates better vagal tone which creates more positive emotions. They also a proposed middle step of a ‘sense of social connectivity’. I should like to add that Kok et al’s work has been legitimately criticised for technical reasons by Heathers, Brown, Coyne, and Friedman (2015). However the theory may still hold, time will tell.
So there we have it our hero of the blog; the Vagus Nerve. I had throught about blogging under the vagus pseudonym. I changed my mind after reading in my Dummies Guide to blogging how angry readers got when a cow (with a dairy company behind it) choose to blog … everyone was all like “you are not a cow, cows can’t blog”. Now vagus nerves seem maybe a lot smarter than cows, but I daren’t suffer the abuse of being considered an imposter.
While writing I have actually been tracking my own vagal tone by a heart rate monitor attached (under my bathrobe, true story). Comparing it to that of my research participants – I am sad to say it isn’t looking good for me.
The extra bad news is that those with a low HRV to start with have a slower increase when they work on it (than those blessed with a good starting point). However to coin a phrase that used to drive me insane ‘it is what it is’ and hopefully I will be able to create some changes in my own physiology as I blog my way through introducing you to yours. Perhaps we all can.
Tune in, in the coming weeks for an overview of vagal nerve stimulation, measuring at home and more.
Meanwhile go well in the direction of your dreams.
Yours, as ever,
Grossmann, I., Sahdra, B. K., & Ciarrochi, J. (2016). A Heart and A Mind: Self-distancing Facilitates the Association Between Heart Rate Variability, and Wise Reasoning. Frontiers in Behavioral Neuroscience, 10.
Heathers, J. A., Brown, N. J., Coyne, J. C., & Friedman, H. L. (2015). The Elusory Upward Spiral A Reanalysis of Kok et al.(2013). Psychological Science, 0956797615572908.
Kok, B. E., Coffey, K. A., Cohn, M. A., Catalino, L. I., Vacharkulksemsuk, T., Algoe, S. B., . . . Fredrickson, B. L. (2013). How Positive Emotions Build Physical Health. Psychological Science, 24(7), 1123-1132. doi: 10.1177/0956797612470827
Pittig, A., Arch, J. J., Lam, C. W., & Craske, M. G. (2013). Heart rate and heart rate variability in panic, social anxiety, obsessive–compulsive, and generalized anxiety disorders at baseline and in response to relaxation and hyperventilation. International Journal of Psychophysiology, 87(1), 19-27.
Young, E. (2013). Wishful Thinking. New Scientist, 13 July.