Part 3 of 4: Vagus nerve stimulation; can you really ‘gag’ your way to good health?

Welcome to part 3 of a 4 part series on the vagus nerve in which I explore whether or not you can gag or splash your way to good health.
First, a little background…
During my PhD (on the vagus nerve) I noticed online health forums talking enthusiastically about the vagus.  It might be like the way you notice pregnant people when you are pregnant. Notwithstanding this some of the content of these conversations alarmed me. Today, I would like to dig into some of that content.
We talked of general lifestyle ways to improve the functioning of your vagus nerve (yoga, meditation etc.) in Part two; today we focus on the specific idea of vagus nerve stimulation.

So what does the science say?

Indeed vagus nerve stimulation is a thing.  It has several decades of (somewhat successful) use in epilepsy to reduce seizure frequency.

Also in 2005 the USA FDA approved vagus nerve stimulation for long-term treatment-resistant depression (Daban, Martinez-Aran et al. 2008).  It is also breaking ground for use in reducing arthritis symptoms (Koopman, Chavan et al. 2016).

The downside – vagus nerve stimulation involves a minor surgical procedure, somewhat comparable to getting a pacemaker put in.  A wristwatch-sized device is implanted in the chest wall. Clearly given surgery is needed (even if ‘minor’) it is not without its downsides and risks.

The good news is, some headway seems to be being made with a device that stimulates the vagus nerve without surgery via the ear (Frangos, Ellrich et al. 2015).

If you google “vagus nerve stimulation” you will see information from chronic illness bodies and association discussing these procedures.  If you google-scholar the same phrase, you will find some of the references below.

Change your search ever so slightly (oh the joys of Google*) to “How to stimulate your vagus nerve” and you get a host of anecdotal and folklore information about exercises you can do at home.  Here are some of the delights you might find:

  • Splash water on your face
  • Gag
  • Hold your breath
  • Try to poop without pooping (called a Valsalva Maneuver)
  • Hold your nose and blow like you are landing in an aeroplane (ditto).

You are also likely to read all manner of claims about what this things might achieve for you in terms of your overall health and wellbeing, or curing major chronic illnesses, even cancer.

So what does the science say about these stimulation ideas?

Not a lot.

I did find that maybe there is something in splashing really cold water on yourself.  A study by Mäkinen, Mäntysaari et al. (2008) indicates that such cold dunking might move you towards parasympathetic dominance.  Remember that is the side of the autonomic nervous system that the vagus nerve is a major part of.  I don’t see any indication as to whether this short-term shift is going to have any long-term benefits.  Maybe have a bucket of ice water on hand for your next terrifying public speaking engagement it just might calm you down while entertaining your audience.

Maybe too there is something in fasting (Mager, Wan et al. 2006) however that probably fits more in the lifestyle section of part 2.

There is also research to support the use of the Valsalva movement to stop a racing heart (Lim, Anantharaman et al. 1998).  I have first-hand experience here as I have a type of congenital heart arrhythmia and have used the Valsalva to stop it.  I have also taught myself the best and latest technigues and asked the researchers personally for more details, there wasn’t much.  It is important to note this is a narrow and specific use of the technique, one should always extrapolate with caution.

When thinking of very specific findings – there appears to be a potential link between the kind of Valsalva one is forced into when pooping on western toilets and heart attacks (Sikirov 1990).  Do go carefully, friends. 

What’s the heads up?

As to whether these ‘exercises’ you can do at home have longer-term health benefits (even if they might temporarily stimulate your vagus nerve).  I’d suggest starting with the tried and trued not rocked science approaches discussed in Part Two.  Or ask your grandmother for general health tips, she is likely to say the same things.

Or perhaps you want to do some experimenting on your own vagus nerve.  Great news – Part 4 will show you how.

Meanwhile go thoughtfully in the direction of your dreams.

Yours as ever,

The WelbeingatworkDr.

Links, References and all that Jazz

*Do remember your google searches are highly personalised.   Uncle Google knows what you have been doing (true story) and incorporates this into what he thinks you might be more interested in.  So if you get the latest celebrity pooping stories – do not blame me.

Here are the parts of this series:

  • Part One: The Wanderer – A Brief Introduction to the Vagus Nerve (our Hero).
  • 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.

Daban, C., et al. (2008). “Safety and efficacy of Vagus Nerve Stimulation in treatment-resistant depression. A systematic review.” Journal of Affective Disorders 110(1): 1-15.

Frangos, E., et al. (2015). “Non-invasive access to the vagus nerve central projections via electrical stimulation of the external ear: fMRI evidence in humans.” Brain Stimulation 8(3): 624-636.

Koopman, F. A., et al. (2016). “Vagus nerve stimulation inhibits cytokine production and attenuates disease severity in rheumatoid arthritis.” Proceedings of the National Academy of Sciences 113(29): 8284-8289.

Lim, S., et al. (1998). “Comparison of treatment of supraventricular tachycardia by Valsalva maneuver and carotid sinus massage.” Annals of emergency medicine 31(1): 30-35.

Looga, R. (2005). “The Valsalva manoeuvre—cardiovascular effects and performance technique: a critical review.” Respiratory physiology & neurobiology 147(1): 39-49.

Mager, D. E., et al. (2006). “Caloric restriction and intermittent fasting alter spectral measures of heart rate and blood pressure variability in rats.” The FASEB Journal 20(6): 631-637.

Mäkinen, T. M., et al. (2008). “Autonomic nervous function during whole-body cold exposure before and after cold acclimation.” Aviation, space, and environmental medicine 79(9): 875-882.

Sikirov, B. (1990). “Cardio-vascular events at defecation: are they unavoidable?” Medical Hypotheses 32(3): 231-233.

Photo by Noelle Otto from Pexels

Part 2 of 4: How to Improve the health of your Vagus Nerve.

Welcome to part 2 of a 4 part blog on the vagus nerve/HRV

Here are the parts:

  • Part One: The Wanderer – A Brief Introduction to the Vagus Nerve.
  • Part Two: How to improve the health of your Vagus Nerve.
  • 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.

First a reminder that Heart Rate Variability (HRV) is probably our best ‘guestimate’ of ‘vagal tone’ or the health of your vagus nerve (and wider Autonomic Nervous System) – see part one for more details.

Today we are interested in how to improve the health of your vagus nerve; our focus is on techniques that have at least some scientific support (even if it is in its infancy).

Let’s start with the bleedin’ obvious.  Exercise is good for your HRV and drinking truckloads, smoking and taking drugs is very bad.  Stress is also bad.

Singing

Singing has been linked to heart rate variability (Vickhoff et al., 2013).  You don’t even need to be good at it.  More mantra type, repetitive or rhythmic singing works better.  It might be all about the breath, which brings us nicely to a pet topic of mine – paced breathing.

Paced Breathing

How often have you been told to “just take a deep breath”.

Before you rush off and do so, it really may not be that simple.

Perhaps what you should be taking is a nice, slow gentle, paced breath.  Breathing in for around 5 seconds and out for around 5 seconds.  The very best approach would be to find your personal ‘resonant breath’.  It is likely to be somewhere around this 4-6 breath per minute.  It depends on a number of things, a key one being the size of your lungs, which clearly is difficult to measure.

Without knowing your resonant frequency (and who does right?), I would go for 5.5 seconds in and 5.5 seconds out, without holding on the in or out.  Why?  A neat study by Lin, Tai, and Fan (2014) compared a range of different breathing patterns and how they influenced HRV.  The winner? 5.5 seconds  in and 5.5 seconds out, no holding.  I have also been ‘playing’ with 3 seconds in and 6 seconds out (from some other information I fell across, I think it is working).

In order to support your paced breathing, there are some great free products on the market.  Simply search for “paced breathing” or “breath pacer” in your app store.  A favourite of mine is called “paced breathing”.  It is super easy to use and allows you to enter half seconds (which some don’t).  It also has a sound option so you can close your eyes.  Nice.

Meditation

There is increasing interest over recent decades by scientists in mindfulness meditation.  Who isn’t mindfulness getting fashionable with – right?

I used mindfulness meditation to improve HRV in my own Ph.D. based on some research on the topic.  Unfortunately, as I dove deeper, I discovered flaws in some of the research.  Then in my own research mindfulness meditation did not appear to improve HRV (cue much self pity).  I suspect that the amount you need to do to make a difference is difficult to get people to do in our over jammed lives.  However, I am leaving meditation in as even 5-10 minutes 3-5 times a week created all sorts of self-reported benefits (around stress, energy, mood etc) to my participants.

HRV Biofeedback,

Now here is something pretty cool.

The idea is – you can use direct feedback on your HRV to improve it.   There does seem to be some research to support this e.g Auditya Purwandini, Muhammad Nubli Abdul, and Nora Mat (2010).  You can ‘try this at home’ via a range of cool interactive tools from the Heart Math Institute.  I have enjoyed these products but am not prepared to state how accurate they are.  I suspect there is a benefit in them and they have published research.  However, I am always cautious where research is funded and undertaken by an organization selling the products.  As you should be eh?

Forest Bathing

In an interesting (albeit small) Japanese study, assigned 12 students to either a ‘forest bath’ (not in a tub, just being one with the forest like), or to watch an urban streetscape for 3 days.  The forest bathers ended up with better HRV as well as other physiological measures (Han et al., 2016).

Yoga

Yoga has been linked to improved HRV (Sarang & Telles, 2006; Satyapriya, Nagendra, Nagarathna, & Padmalatha, 2009).

Diet

A quick look shows me there is not a huge amount of research on Diet and HRV.  I did discover fish (specifically tuna) is linked to HRV (Mozaffarian, Stein, Prineas, & Siscovick, 2008).  I suspect diet is likely to fit into the bleedin’ obvious stuff.   Poor HRV is a risk factor in heart disease and we are all aware of the general heart disease goodies and baddies (even if some of them have changed over the years – eggs anyone?).

The End

So there we have it, some great places to start working with your vagus nerve/HRV.

There has been a lot of interest in certain unusual techniques e.g. blowing, gagging, bearing down (like you are a going to poop).  These will be covered in part 3 of this series.  In Part 4 you will learn how to measure your own vagal tone at home.

Thanks for dropping by,

Go well in the direction of your dreams.

Yours as ever,

The Welbeing@WorkDr

References

Auditya Purwandini, S., Muhammad Nubli Abdul, W., & Nora Mat, Z. (2010). Heart Rate Variability (HRV) biofeedback: A new training approach for operator’s performance enhancement. Journal of Industrial Engineering and Management, 3(1), 176.

Han, J.-W., Choi, H., Jeon, Y.-H., Yoon, C.-H., Woo, J.-M., & Kim, W. (2016). The Effects of Forest Therapy on Coping with Chronic Widespread Pain: Physiological and Psychological Differences between Participants in a Forest Therapy Program and a Control Group. International journal of environmental research and public health, 13(3), 255.

Krygier, J. R., Heathers, J. A., Shahrestani, S., Abbott, M., Gross, J. J., & Kemp, A. H. (2013). Mindfulness meditation, well-being, and heart rate variability: a preliminary investigation into the impact of intensive Vipassana meditation. International Journal of Psychophysiology, 89(3), 305-313.

Lin, I., Tai, L., & Fan, S. (2014). Breathing at a rate of 5.5 breaths per minute with equal inhalation-to-exhalation ratio increases heart rate variability. International Journal of Psychophysiology, 91(3), 206-211.

Mozaffarian, D., Stein, P. K., Prineas, R. J., & Siscovick, D. S. (2008). Dietary fish and ω-3 fatty acid consumption and heart rate variability in US adults. Circulation, 117(9), 1130-1137.

Sarang, P., & Telles, S. (2006). Effects of Two Yoga Based Relaxation Techniques on Heart Rate Variability (HRV). International Journal of Stress Management, 13(4), 460-475. doi: 10.1037/1072-5245.13.4.460

Satyapriya, M., Nagendra, H. R., Nagarathna, R., & Padmalatha, V. (2009). Effect of integrated yoga on stress and heart rate variability in pregnant women. International Journal of Gynecology & Obstetrics, 104(3), 218-222.

Vickhoff, B., Malmgren, H., Aström, R., Nyberg, G., Ekström, S.-R., Engwall, M., Jörnsten, R. (2013). Music structure determines heart rate variability of singers. Frontiers in psychology, 4, 334. doi: 10.3389/fpsyg.2013.00334

Part 1 of 4: The Wanderer – Aka the Vagus Nerve

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.

Fight or Flight Response

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

Vagus Nerve and Heart

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.

Social Support and Vagus Nerve

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, to following epispodes for an overview of vagal nerve stimulation, measuring at home and more.

Meanwhile go well in the direction of your dreams.

Yours, as ever,

The WellbeingatWorkDr

References

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: www.pexels.com/photo/love-heart-romantic-romance-37410/

The Vagus Nerve and Work Performance

Note
This blog originally appeared on the University of Western Australia’s Business School Blog and is a laypersons overview of what my PhD was about.

What does your heart have to do with it?

Has it ever occurred to you that how well you do at work might just be connected to the variability in your heart beat?  I am not sure about you; I always assumed you would want your heart to beat smoothly, rhythmically.  However there is an ancient Chinese saying that goes something like this “a man whose heart beats like a drum, will be dead before sundown”. In the 21st century it looks like these chaps were on to something.  It turns out we actually want a heartbeat that changes ever so slightly as we breathe in and out.
There is a lot of science and research that explains why this is the case; loosely it goes like this – you have a spectacular nerve called the vagus nerve that connects your brain to many of your major organs.  The term vagus is Latin for wanderer, as indeed this nerve wanders throughout your body.  This wanderer is the major component of your parasympathetic nervous system.  Among many important functions in your body, this nerve has control over your heart beat, working to slow it as you exhale and speed it up as you inhale.  This is a good thing – called high vagal tone.
High vagal tone indicates your vagal nerve and wider nervous system are in good shape. As you can well imagine if your nervous system is in good shape, you too are likely to be in good shape.  Healthy vagal tone (or high heart rate variability) has been linked to an amazing range of things. It is shown that people with a healthy vagal tone are likely to perform better on cognitive tasks, be happier and perceive themselves as more socially connected.
Now I am sure you are thinking – what can I do to improve my vagal tone?  The common belief amongst scientists used to be that you couldn’t improve, that you were born with a good or not so good vagal tone.  It was the luck of the draw, if you will.  However more recent research shows you can (probably) lift vagal tone via exercise, yoga, and even special breathing techniques, or lower it in similar but reverse ways, or by having vodka on your corn flakes every day.
Some of this research (way back in 2012) got my PhD supervisor Kerrie Unsworth and later me thinking … surely all this stuff (I mean cognitive performance, happiness, social stuff) is going to have an influence on work performance.  And so my PhD was born and named “The Wanderer: Vagal Tone to Worker Performance”.  ‘She’ has been recently submitted and I eagerly await the reviewers feedback, after which I will share more with you on the findings.  For now here is a four part series on HRV and how you can measure and improve it yourself.