This is the first of a series of blog posts on the new rock star of the holistic health world – the vagus nerve. It just so happens that the vagus nerve (and work performance) was the topic of my Ph.D. hence I would like to equip you with information you can trust (before someone suggests you can cure your cancer by gagging or splashing cold water on your face to stimulate your vagus nerve, because yes this is out there).
This post will provide a brief overview of the physiology. As this is the foundation blog for more practical (and perhaps more interesting) things to come – I will cover just enough to support you on the journey through the coming blogs.
Future blogs will cover:
- Part 2: How to improve the health of your Vagus Nerve – based on scientific evidence.
- Part 3: Vagus nerve stimulation; can you really ‘gag’ your way to good health?
- Part 4: Do try this at home; monitoring your own vagus nerve health using the variability in your heart rate.
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, gallbladder. 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. 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 the ANS as a brake and an 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 brake 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. However accelerators in cars are not bad, are they? They are just bad when the driver forgets about or can’t use the brake. 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.
Where the SNS has become the accidental villain, the opposite is true for the vagus nerve which has become the hero, the 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.
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 the vagus nerve 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.
Good heart rate variability (or vagal tone) has been linked to a host of mental and physical benefits. 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 saber 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 a diminished vagal response in those with social anxiety.
The work of Kok et al. (2013) goes further still and proposes 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. I will say 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.
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.
Cover photo source: http://www.pexels.com/photo/love-heart-romantic-romance-37410/