Headaches, atrial fibrillation, epilepsy, anxiety and depression? While these conditions may seem unrelated they may all benefit from a potential treatment involving gargling and the vagus nerve.
The vagus nerve is a major neuronal pathway of the parasympathetic nervous system, our rest-and-digest system. Known as the “wandering nerve” because it branches all throughout the body the vagus nerve has far-reaching effects which include involvement in swallowing, speech, heart rate, respiratory control, gastric secretion and intestinal motility.
In this episode Andrew speaks to Emrys Goldsworthy, a Senior Lecturer and Musculoskeletal Therapist, about the use of vagus nerve stimulation (VNS) to improve health and wellbeing. As an expert in VNS, Emrys takes us through the research behind this therapy and shares with us some techniques for harnessing the vagus nerve.
Covered in this episode
[01:04] Introducing Emrys Goldsworthy
[02:04] Introducing today's topic - working with the vagus nerve
[02:30] Emry's background
[03:02] Exploring the nervous system more deeply
[03:47] Vagus nerve and the gut-brain axis
[05:26] Historical medical interventions with vagus nerve
[06:52] Current methods of vagus nerve stimulation
[11:44] The actions of the vagus nerve
[13:32] Vagus Nerve: anti-inflammatory activity
[15:42] Are these effects measurable?
[16:52] Comprehensive discussion of the evidence
[31:40] Is there a way to assess low vagal tone
[38:18] At home techniques for the vagus nerve
[42:16] Research portfolio in this area
[45:43] What other areas can vagal stimulation benefit?
[50:20] Any issues to be aware of with therapy?
[52:33] Home treatment devices
[54:14] The future of therapy
[56:36] Where can practitioners get training
[1:01:04] Final thanks & conclusion
Andrew: This is FX Medicine, and I'm Andrew Whitfield-Cook. Joining me on the line today is Emrys Goldsworthy, who is the director of Athletica Physical Health in Brisbane, Queensland. He completed a Bachelor's Health Degree in health science musculoskeletal therapy, which he attained at Endeavour College of Natural Health, formerly the ACNM. He's also gained a Master's Degree in sports coaching, focusing on classical ballet coaching at Griffith University. Emrys has been a lecturer since 2008, and currently holds a position of senior lecturer of the department of musculoskeletal therapy at Endeavour College of Natural Health in Brisbane.
Emrys' interest in the body began when he was a professional classical ballet and contemporary dancer. He is a graduate of the Australian Conservatoire of Ballet, which led to a career in the Royal New Zealand Ballet, performing several soloist roles and touring the world with the company. Emrys has a unique approach in the examination and treatment in physical impairments.
Today we're going to be talking about something which is greatly interesting to me, and I've got to say I am totally ignorant of, and that is working with the vagus nerve. So welcome, Emrys, to FX Medicine.
Emrys: Thanks for having me.
Andrew: Emrys, I've got to say, I feel like a dunce with this. The only vagal nerve stimulation that I'm aware of, being a nurse, is the more medical stuff with an implant and electrode. But I'm getting the gist that we're going to be talking about something completely different.
Emrys: Yeah. Yeah, indeed.
Emrys: Yeah. So originally, I was a classical ballet dancer with the Royal Museum of Ballet. I ended up retiring to come back to Australia and move on to a new career. And I did my Bachelor of Health Science in musculoskeletal therapy and graduated, moved into lecturing and clinical practice after that, in 2008.
And at the time, I was lecturing but also just sort of specialising in dance injury management and just normal clinical work, and it wasn't 'til much later that I started to get a bit more interested in the nervous system. At the time, it was just a small part of the way I was thinking, as far as injuries were concerned. And then I found… I started learning a lot more about chronic pain and neuropathic pain, which led on to thinking and talking in class about it, and learning more about neuroplasticity, and being inspired by a lot of authors in these areas. Eventually, that moved on to some interventions that were out there, neurostimulation, photobiomodulation, also known as low-level laser, and vagus nerve stimulation.
Vagus nerve stimulation was an interesting thing for me. That came about quite organically over the last few years, and I was really surprised that not many people were talking about it. You know, you'd hear a lot about the gut-brain axis, and that's what you'd hear from all my colleagues in naturopathy and clinical nutrition. Then I started hearing about the brain-gut axis, and I thought, “Oh, okay, this is interesting. Maybe I can assist some of the naturopaths with my nervous system work.”
Because everything I do, as far as nervous system work, is really not to do with… no supplementation or anything like that. It’s all physical approaches, manual approaches. And I thought, “Well, how can I assist in this?” And I read up more on it, and found that it was really relating to the way that the vagus nerve impacts on gut health and reducing gut inflammation and a range of other things.
So I thought, “Oh, okay, it's more than just stimulating the muscles of the gut. It's a bit more than that.” And when you go in-depth into this, you get shocked at how much the vagus nerve does. Way more than you learned at uni. And it gives you a bit of an idea of how important it is.
So when it's not functioning very well, that's when you start to go, “Ah, maybe we can do something about that, and maybe it'll have a big impact on… firstly, what it will mean for just gut problems.” So, that's where it started. I thought, “Okay, vagus nerve, gut problems, there's a link there, maybe we can stimulate it in some way.”
Emrys: That's right.
Andrew: But the only real medical interventions to the vagus nerve were basically dissection to stop things like nausea, or indeed, there may be some impart in vasovagal stimulation, that sort of issue.
Emrys: Yep. Yeah, so vagotomy is a real thing you read a lot about in the literature. And a lot of that stuff, for me, is important in understanding what it...when you have that, what goes wrong after and all the side effects of that, as to know whether...
Andrew: Yeah, it wasn't a...
Emrys: ...that's why sometimes stimulation is important.
Andrew: It wasn't a nice therapy in any way, shape or form.
Emrys: No. No, no. Well that's completely so far removed from what we… the research as where it is now. The other stimulation device is, of course, the implanted device for recalcitrant epilepsy. And of course, that's being utilised by a fair amount of people in the United States.
Emrys: Most of the research is done over there, and they're getting great results. There's some side effects to it…they're usual things with any implanted device, infections and the like. But a lot of the research is done on that particular device, but the emerging field is what's called transcutaneous, or non-invasive vagus nerve stimulation. So that's where I sit.
Andrew: Great. So I've got to say, like, you said when you started to learn about...you know, let's call it transcutaneous vagal nerve stimulation, when was this? And has that research evolved since when you first learned about it?
Emrys: Yes. So a few years back, one of the first things I started to do was utilise some exercises that activated some of the motor output of the vagus nerve. And that was really things like gargling, sometimes singing, because the vagus nerve is involved in vocalisation, and also in gargling and the range of all the muscles at the back of the throat. So there are some things we could do in that way, the take-home exercise.
But the whole idea of electrically stimulating it, well, we started with electrically, light electro-stimulation through the neck where the axons run. But I always knew this was a problem because of my background, I do a lot of work in neuroscience. I teach neuroscience here at Endeavour College, and that's my main area of sub-expertise.
And I knew that… it didn't make sense to me to stimulate along the axon. The electrical stimulation of the nerve starts at one end and into the other, it's not meant to occur along the axon.
Andrew: Halfway through, yeah.
Emrys: Yeah. And so I always found that the idea that they were stimulating it along it’s axon to be not based in the neuroscience of it. So I thought “We need another way.” Is there any other sort of...we call it a sort of end-organ, which is like the receptor zones, or at sensory zones that the vagus nerve accommodates?And we found articles, the outer part of the ear is vagus nerve innervated, and I thought, “Ah, interesting.”
Emrys: And then I did some research, and it turns out that the body of work, a lot, at least thousands and thousands of papers on auricular transcutaneous vagus nerve stimulation. You would never know about it, and it seems to be...and it's at pretty reputable universities across Europe and America. And this just led me on a completely different track, and I started looking into doing auricular stimulation, and played with different frequencies and different approaches to stimulation.
So we have one type, which is electrical stimulation through filiform needles. They're the ones they use in dry needling in acupuncture. So you can use them to put the needles in the ear, and electrically stimulate via them. Or you can use electro-stimulation devices like TENS machines and things.
The problem is with the ear is that it's quite a small area, and the actual vagal innervation is quite small. If you want to get more effective with it, you need to make your own device. You pretty much have to start from scratch. So, that's why we tended towards small needles, because you can really be accurate with them.
Andrew: Yes. I was looking at a device...and forgive my ignorance because I'm not an expert in this at all. But I was looking at a device that basically looked almost like a clip that you clipped onto the auricle...
Andrew: Is that right?
Emrys: Yeah. Yeah, so a lot of the research is done with clips on different parts of the ear. And one particular study was fantastic, they had the sham just on the outside part of the ear, which is the trigeminal nerve. And then on the concha in the actual group that they were testing, which is the vagus nerve, which is the inner portion. They found that the one that was done on the concha actually activated - and we'll talk about its effects - all the effects of the vagus nerve, all the antidepressant effects, and all the brain regions lit up dramatically in functional MRIs. But then the one on the outside part of the ear had no effect.
Emrys: So it's amazing how different parts of the ear, and the different effects it has on the brain. Which is quite shocking when you consider that the vagus nerve looks more like a gastrointestinal, heart, and lung kind of nerve, it seems to have a lot of brain effects as well.
Andrew: Yeah, so this is...well, I'll ask you about that next, but can I just clarify something? Am I getting this right, that the place where they stimulated was just below that sort of horizontal-ish ridge in your ear? Is that right?
Emrys: In the middle part of the ear, just close to the external auditory meatus, and so the upper and lower part of the concha, which is the centre part. I think we're going to have a look...
Andrew: Upper and lower, got you.
Emrys: Yeah, upper and lower. But there's recent research today that the most densely innervated area is the upper portion, which unfortunately in most people is the smallest area.
Andrew: Right, okay. Got you.
Emrys: It's tricky clinically, yeah.
Andrew: No, I remember looking at it, going “wow.” But anyway, so for our listeners and for me, please, apart from the obvious that we learnt in Anatomy & Physiology 101, can you take us through the actions of the vagus nerve? Because it just seems to be so much more than what I thought it was.
Emrys: Yes. So, I'll take you through some of the basics. So of course, it's the main parasympathetic nerve. And a little word of warning: when you learn about… you know, this is this unfortunate thing that people get taught is that essentially, when your vagus nerve is really active, or it's healthy and working higher than it used to be, they think that it's going to overly lower your heart rate and you're going to go into bradycardia. And you're going to have lungs that you can't breathe properly because your breath rate is so low...
Andrew: Well, it's only one of the controls...
Emrys: ...or your gastrointestinal motility will go too much. It doesn't really work that way.
Emrys: What it really does when it's active, it more modulates everything. It more brings it back to homeostasis, you could say. Because really, all it's about is the aftereffects of the sympathetic response, the fight or flight response. That parasympathetic response is all about returning it to normal, just down-regulation, rather than complete suppression.
Emrys: And I think that's very important. So you see a lot of that, a lot of people are talking about “Oh, if you stimulate the vagus nerve too much won't you get this effect, or this effect…?" And it doesn't really work that way. It's not really dangerous.
Emrys: So, some of these are, of course...it increases gut motility and contraction of smooth muscle cells in the gut lining. It's also involved in regulation of heart rhythm, so it tends to lower the heart rate but modulate heart rate. It's involved in swallowing and the gag reflex and vocalisation.
And then the big thing is about its involvement in an anti-inflammatory pathway, which has only recently being found out. But it has direct connections through three anti-inflammatory pathways throughout the body. And one being it activates the HPA axis without the stress response. So it hasn't got all the secondary stress response effects, but it does activate the HPA axis so you get an anti-inflammatory effect through cortisol through that one.
You also activate this other one through the coeliac ganglion in the gut, and that activates lymphocytes in the spleen to release acetylcholine on macrophages. And this is a really interesting interaction. So when the lymphocytes release acetylcholine onto splenic macrophages, the macrophages are inhibited from releasing pro-inflammatory cytokines, particularly TNF-alpha.
Emrys: So, it's involved in that anti-inflammatory response. But the most amazing one, which is where I started, is its role on the gut lining.
Emrys: So it directly, via enteric interneurons and neurons, it releases acetylcholine onto gut mucosal and gut-lining macrophages, and it has the same effect. It stops it from producing TNF-alpha and interleukin-1, and as an effect, they say that, potentially, interleukin-6 as well.
Emrys: So you've got this huge anti-inflammatory effect, which has huge potential for things relating to inflammatory bowel disease, and also rheumatoid arthritis. So all these autoimmune conditions, that's where a lot of that particular cholinergic anti-inflammatory pathway, that's where they're pointing the research into those areas. But that's the next step, is really more in that area.
Andrew: I mean, I'm thinking about IBD certainly right now, with TNF-alpha and interleukin-1B, and that's really amazing. Can I ask, then, is this a measured effect? Like you can prove before and after, and...
Emrys: Well, they've got the ability to see blood levels of interleukin levels and TNF-alpha levels drop before and after, and they've done this research through the pathways and found that it actually occurs. And yes, they see the before and after changes.
It's directly reflected into a range of other conditions. You see it in IBD, but also in increased gastrointestinal...decreased inflammation in BGIT and other conditions, but then...you know, this is the next area for research. They've established those pathways.
Emrys: They know that the pathway to the macrophage and the gut lining is 100% established, it's the other two that they're trying to map out better. And so the HPA axis is definite, it's just that the minor circuitry needs to be mapped out better. And it's happening, but it’s... you should see the research. It's 2016 and next year, it's all occurring right now.
Andrew: Oh, wow.
Because depression is one that you wouldn't expect, necessarily. But they found that when they were treating people with epilepsy with the implanted device, that a lot of them who had depression as well were saying that, “Oh, a lot of my depression symptoms are decreasing.” And this was a consistent finding throughout all the research.
So they started to look into it, and they found, indeed, there are tens and tens of research articles on the antidepressant effect of vagus nerve stimulation. And it has been followed up with auricular transcutaneous, and is having the same effect.
Emrys: So you don't have to do the implanted device, you can have the auricular stimulation, and have the same effect. And so a lot of this comes down to the circuitry. So what they've found is that it activates a couple of areas in the brain stem.
So mainly, it activates a thing called the locus coeruleus, and this is our main nuclei group that has extensions throughout the brain, throughout the spinal cord as well, and it releases norepinephrine or noradrenaline. And so when you activate the vagus nerve, it activates one of its nuclei group, and then onward from that it activates the locus coeruleus.
So when you activate the locus coeruleus, you get high concentrations of norepinephrine throughout the areas of the brain, particularly the areas in the brain that are involved in depression, and lower levels of norepinephrine in depression.
So some of these are areas that you'd tend to see an increase, mainly areas of the hippocampus, and also in the frontal cortex. And so these areas, essentially, would normally see lower concentrations, and hence seeing norepinephrine reuptake inhibitors as one of the treatments. And instead of just a replacement of the neurotransmitter, it up-regulates the nerves and neurons that produce it. So it's like exercising the system that is going to decrease the depressing symptoms.
Another interesting thing is that they found that in a couple of studies, I've got some numbers, the vagus nerve stimulation increased norepinephrine levels by 69% in the hippocampus, and 70% in the prefrontal cortex, the medial prefrontal cortex.
Andrew: Oh, sorry, over what time are we talking about? Are we talking about an immediate increase, or are we talking over a treatment phase?
Emrys: An immediate increase, and progressively over treatment phase as well. It actually works an immediate change, and also, people get it while they're doing it.
Emrys: So the levels go up while they're doing it, and then after. Of course, it's that stimulation, and then you get the secondary effect after. And then over time, these neurons actually get stronger and stronger and stronger, and so the baseline levels will improve, and therefore the percentage increase will decrease.
Andrew: No, but that's really interesting. Like, this is just way out… Like, I'm just...forgive me, I'm just clicking on a couple of papers, and I don't know the significance of them, but I'm just looking here about GABAergic and cholinergic...
Emrys: Yeah, so that's the...we haven't even got to the GABA effects. I'll get to that.
Emrys: I'll just add to the noradrenaline because the picture is not complete, because we haven't talked serotonin.
Andrew: Ah, yes.
Emrys: So, the serotonin nuclei group is the raphe nuclei, and the dorsal raphe nuclei sit relatively close to locus coeruleus. And of course, the vagus nerve doesn't directly stimulate the dorsal raphe nucleus, or raphe nuclei, but it does via the locus coeruleus.
So what tends to happen is that the secondary effects are the same in that serotonin levels go up as well as norepinephrine levels go up, but it's going to because the locus coeruleus gets activated. If that didn't happen, you wouldn't get the change in serotonin. Now unfortunately though, serotonin changes occur two weeks later.
Emrys: It takes time. It takes time. So that's why adherence to treatment is so important.
Andrew: And is that only in the brain, or what about in the gut?
Emrys: Yes, it's brain only. Right, right.
Andrew: Brain only.
Emrys: Yes, well they only assessed brain, so...
Emrys: ...I don't know what's going on in the gut at the same time. But you know, we tend to simplify with neurotransmitters, we say, “Oh, this neurotransmitter does this, and this neurotransmitter does this.” The thing is, that depending on where it is in the body, it does very different things.
Emrys: We know that serotonin has an anti-nociceptive effect in the spinal cord and the brain...particularly in the spinal cord, sorry. Then in the peripheral nervous system, it actually is a pro-inflammatory. So it just depends on where we're talking about. So...yeah, it's always important to be aware of that.
Andrew: So what about its utility with things like irritable bowel syndrome, where there may be dysregulation of serotonin receptors in the gut? Because what is there, 147 and whatever else, with regards to peristalsis...
Emrys: That’s a bit beyond my knowledge.
Andrew: Okay. Because...wow, because that's really interesting.
Emrys: Well, think about it like this, and this is, unfortunately, a little bit broad, but it's a good starting point. If we consider that the maintenance of the tissues of the gut lining are maintained by the vagus nerve. If we also consider that the gut's afference, all the sensory input receptors as for inflammation, how much pressure there is, all the different receptors in the actual gut, or through the majority of the gut, the first portions of the gut go through the vagus nerve.
Then you have the amount of activity as far as peristalsis is concerned. So a lot of it, from a neurogenic perspective, neurological perspective is mediated by the vagus nerve. If you don't have enough activity in the vagus nerve, you could surmise that a lot of those neurotransmitter problems, is sort of a secondary effect. You could say that, but there's not enough research to back that up yet because it's not been looked at, from my understanding.
Andrew: Got you.
Emrys: I wish it had because I would love to answer that and go, "Yes! We have that. We have that."
Andrew: Talk about piquing my interest because my mind's going every which way. I'm talking about…like what about chronic regional pain syndrome, what about hyperhidrosis? There's so many, so many areas that...
Emrys: So listen, I've got a few things that...just to pique some interest, just to confuse you even more...and a lot of this we don't know why, but...
Okay, so over, I think it's over a treatment course, I can't remember the months. A lot of them are done in a month, and it's very important to remember that depending on what…it’s globus, the device that's implanted.
Emrys: Now, again, it's been shown that time after time that transcutaneous can work just as well, if not better because of the less side effects.
Andrew: Side effect, yeah.
Emrys: It's shown to decrease cluster headaches, severity and frequency. And that was in 2016, in Cephalalgia, the publication.
Emrys: It also decreases interleukin-17 alpha, a pro-inflammatory cytokine, seen after myocardial ischemia. And so there's a whole heart effect we haven't even gone into. Vagus nerve also… Vagus nerve stimulation also has an effect on autism...
Emrys: ...that's shown to, at this point only modest, but definite behavioural improvements.
Andrew: Modest is better than nothing.
Emrys: Well, indeed. It's also, when you utilise vagus nerve stimulation in combination with rehabilitation exercises, it actually...
So if you have a group that has been doing rehabilitation for, say, a limb, or whatever it is, it doesn't matter what it is. And then you have a group that's having VNS done at the same time…I believe this study was using auricular, and one of them actually used a take-home device, so we'll go into the use of take-home devices, and doing the same rehabilitation exercises.
The group that did the VNS as well as the… compared to the no-VNS group, they had a far greater representation of the area being moved in the brain post-rehab. So that means that the motor cortices had a more clear and bigger representation of the region being rehabilitated.
Emrys: So what you tend to see is, you see these changes in the brain and the motor cortex with chronic pain and the like. And when you see that there's a change in the representation of that area, it becomes more specified, more specific to that...
What you tend to see, for example, if you've got chronic hand pain, and you've got one finger involved, well, you see a merging of multiple fingers in that region of the brain. So it tends to become more broad, the symptoms associated with the motor areas. So that issue means that we can modulate the amount of neuroplasticity and upregulate that, and increase it by doing vagus nerve stimulation with the rehabilitation.
Emrys: Which you'd never think you'd do that, right?
Emrys: And that goes back to other studies that show massive increases in brain-derived neurotrophic factor after vagus nerve stimulation.
Emrys: So that fits because you've got the stimulant there.
Andrew: Yeah, yeah. Yeah. I've got to say, like...are you aware of the Swinburne University neuro-psycho imaging department with Andrew Scholey, Professor Andrew Scholey?
Emrys: I'm not, sorry. Well, being from Brisbane, I probably know half…
Andrew: Well, really, really interesting stuff they're doing down there. But boy, it'd be great to introduce you to them. Wow.
Emrys: Oh, yeah. I've been looking into some research options for this because… and it's just where do you go? I mean, for me, I've been in chronic pain and neuropathic pain, and I see a lot of opportunity there, and there's a lot of research being done. I haven't discussed that yet because a lot of it's still in process.
But, so we've got locus coeruleus and a range of raphe nuclei being activated, well, these are parts of the descending pain inhibition system, which is dysfunctional in chronic pain.
So, people are talking about changes in migraine. Migraine is one of the other hugely effective...a few hugely important areas to consider with vagus nerve stimulation because they had changes. One of the studies showed with non-invasive vagus nerve stimulation that a group of migraineurs, migraine sufferers, 71% of them had a decrease in their symptoms one hour after treatment. And two hours after treatment, 50% of them had no pain at all.
Emrys: And we're talking about people who have extreme amounts of pain in this study.
Andrew: Yeah, debilitating.
Emrys: Debilitating is right. And so more research needs to be done because we need to see it over bigger groups, so that we can get a better idea.
Andrew: For sure.
Emrys: But I mean, these are fantastic results. And they're a huge result. They're not just small improvements, they're huge. So I mean, you can imagine...I mean, I'm not saying people need to change what they're doing right now. I just think what if...this could be an adjunct for a lot of different conditions.
Andrew: Well look, even orthodox neurologists aren't really happy with the treatment for migraineurs.
Andrew: I've spoken to one who just said, look… He actually looked at judicious adjunct supplementation because his migraineurs just weren't getting the results that they were happy with from the existing medications.
Emrys: Hmm...no, that's right.
Andrew: So I mean, anything that you could give them...these people are...it's not just a headache. These people are debilitated. I've seen one that looked like a stroke.
Emrys: Well, you get...and sometimes you get a lot of other neurological symptoms as well. And there's a range of theories I work by, but yet to be really explored and researched with the way neurons decline over time and poor use. I mean, one of the main things that I've considered is: why does the vagus nerve become so problematic?
And it's not that people have got dramatic, like, diseases of their vagus nerve. I don't believe that, necessarily. I just think that with the amount of stress people are under these days, and the amount of sympathetic tone and low heart rate variability a lot of people end up having, this basically will, by default, inhibit the vagus nerve. And that's not very good as far as maintaining the hardware of a neuron.
So when nerves don't get fired off regularly, they actually decline. They don't necessarily die, but they decline, so then they become less effective at firing. So you can imagine when… Okay, you're chronically stressed, and you inhibit your vagus nerve pathways because they just don't get used very often, okay? They don't get used enough, let's just say.
Emrys: Okay, and then you have some gut inflammation, and your vagus nerve senses that. But because it's not really strong in its firing pattern, and its frequency of firing is lower than it should be, it ends up being a bit lagging behind on its anti-inflammatory response to that.
So what you'll see is that the vagus nerve works kind of like a negative feedback loop with gut inflammation. If the inflammation goes up, the vagus nerve senses that through afferent, and through an efferent output through the cholinergic anti-inflammatory pathway we already mentioned, and blocks the release of the cytokines, the pro-inflammatory cytokines.
So you're seeing this modulation of the inflammation levels so it doesn't get out of control. But what you see is it does get out of control in a lot of people. And that could be one of the reasons why. It's very difficult to ascertain where it's starting, where… is it that they've got low vagal tone, or they've just got too much sympathetic tone? It's probably a bit of both.
Emrys: Yep. So you've got to get heart rate variability checks.
Emrys: Because generally speaking, that's the gold standard for vagal tone, okay? And I know that's a heart-related test, but if you see whether your heart rate...
Andrew: Vaso-vagal syncope, yeah.
Emrys: Yeah. So if your heart rate variability is lower, that's sort of indicative of high sympathetic and low vagal tone.
Emrys: So higher sympathetic, and low vagal tone. So you want higher heart rate variability. And so in our clinic, you can use a software called HeartMath, that's a useful one, but we do other tests as well.
You can do other tests that give you a broader picture. So, you can look at bowel sounds. As a clinician, you can look at bowel sounds and see whether they have the loudness, the tone, the regularity there. If it's disorganised, if the sounds are maybe under 30 per minute or less, that might indicate...or discoordination of them, that might indicate some vagal nerve problems.
Breath rate, it's difficult with respiratory rate because there's a lot of factors with respiratory rate. I wouldn't use that as a primary test. Another one is gag reflex, and you hear in the literature that a lot of people don't tend to have much of a gag reflex. So when you touch the soft palate at the back of the throat, it elicits the gag reflex. Now, I do wonder whether that is because there's a lot of people with low vagal tone, or...you know, that may not be the best test alone. Another one is the ability to elicit the uvula. So when your doctor says, "Ahhh..."
Andrew: Ah, yeah...
Emrys: ...and they depress their tongue, and... So the ability of the uvula to elevate is vagus nerve mediated, so that might be a test that I use in conjunction with others. And to me, it's all about everything together.
Emrys: And if it all starts to show a theme, I start to say, “Okay, you've got...your vagus nerve is less active than ideal."
Another one I didn't mention is vocal cord exams. So I've had a few patients in the past, and they weren't coming to see me for vocal problems, but they said… it's a bit anecdotal, I know, but all their problems started around a similar time.
And some of them as opera singers, they stopped being able to sing. Mainly because they couldn't go from low to high notes. They found that it was difficult, and they didn't know why. No one could figure out why, and there was no problem with their vocal cords that they could see on the scans and at the examination. And then it turned out that they've actually got low vagal tone.
And so that actually fits that it could have been the fact that the vagus nerve somehow was inhibited, and it affected their vocal production, their vocalisation. And so a lot of them, their symptoms, their secondary symptoms which is what they'd come to see me for, maybe it's an inflammatory problem, a depression, for example. They's come to see me for maybe that, but they'd all started around the same time.
So it's that “never well since” principle, and it may well have started with the vagus nerve. I can't prove it, but it seems to me that...I've seen it multiple times, and it all seems to come about when their vocal cords change.
Andrew: So can I ask with regard to that, and the reason is because there's a...she wasn't a patient, it was a friend of a friend, so somebody who just had something horrible…a horrible life experience happened to her, and from that moment on, she could only speak in a whisper.
Emrys: Ah, yes.
Andrew: Now, back then in my nursing days, I had no idea, I did my “psychosomatic.” I'm wondering, I don't know, obviously, this is an old, past-tense example, but I just wonder if...do you find any correlation with stressful events with these sort of singers?
Emrys: Yep, yep. Yep.
Andrew: Really? Oh, wow.
Emrys: Yeah. And so my presumption is, like I said before, you have a stressful event, and you have this exaggerated sympathetic response.
Andrew: Yeah, yeah.
Emrys: You know, it's not well controlled by...maybe you already had a bit of a lower level, low activity in your vagus nerve, who knows, but the ability to regulate that stress response maybe wasn't there. For whatever reason it was, it inhibited your vagus nerve and your parasympathetic nervous system as a whole.
And that happens on a chemical level, that's not just because it's not activating. It happens on a chemical level because the norepinephrine gets released on presynaptic cells, so they actually inhibit the presynaptic cells of synapses. And so over time, if you keep inhibiting it, it's just going to down-regulate it. So it finds it much harder to activate. And so it would make sense that in extreme cases, some people actually go to the point where their vocal cords don't work as well, because the vagus nerve outflow is so reduced.
Emrys: Yeah, I could definitely presume that.
Andrew: When you were talking about the bowel sounds, and borborygmus is part of that, but...or it's more of a pathognomonical sound. But something that interested me, or tweaked my interest in that was, do you find a great confusion if you just looked at bowel sounds with something like small intestinal bacterial overgrowth, SIBO? Do you differentiate there, or is there a link, or...?
Emrys: Yeah, so I wouldn't...because like I said, unfortunately, these tests are never really good by themselves. I would never use them by themselves. So any abnormality I see there, what I tend to do is I think more functionally, okay?
Because I'm not really...I don't work on SIBO directly. I mean I do, but I don't. The way I see it is I'm going...my main role...because I work a lot with Ananda Mahony, you've talked to her previously...and so we'll tend to work on these together.
So my role in that whole picture is not to treat, necessarily, the SIBO directly, I'll treat it by improving the hardware. Again, my role is to update the hardware, and update the software so that the hardware works better.
Andrew: Yeah, yeah.
Emrys: So it's all about improving the neural connection there so that everything that occurs there will happen more efficiently, and so whatever intervention that the naturopath or the clinical nutritionist might have, it could work better.
Emrys: Because it does, it relies upon the vagus nerve actually working. If it doesn't work, well, it may not be as effective, and that may be why some people don't respond. I mean, I presume that. I don't know that for sure, but it could be a reason.
Andrew: Can you take our listeners through some of those?
Emrys: Yes. All right, so what I tend to give my patients, and these are pretty easy to do. One is...singing is an interesting one. A lot of people don't like singing. And I always explore why you don't like singing.
Andrew: I love singing. My family hates me singing...
Emrys: Yeah. Well, that's the tricky thing to singing. And it's only in particular places you can do it, of course. So, singing is a good one. You can join singing groups. It sounds strange, I know that, but you know, the fact that I put needles in someone's ear and I'm affecting their gastrointestinal tract is very strange. But this whole vagus nerve stimulation is very novel.
And so one of them is singing, particularly if you can do high to low tones, not just monotone-type singing or anything like that. Get in there. I think in part I prefer more classical singing, if possible. If not, just maybe more of a training, as far as doing a range of levels of tones and so on.
Emrys: And I think it's also good to do it in groups because you actually get in a bit of social interaction. A lot of people I deal with in chronic pain, they don't really have social connection sometimes, and sometimes it's their social problems that are causing part of their problem.
And so getting them into singing groups is actually a strange but really novel way of actually getting them out there, meeting new people, enjoying it, but also doing something else, actually stimulating their vagus nerve.
Andrew: Absolutely. Yeah.
Emrys: Another one that's really easy to do is gargling. And a lot of people say, "Oh, I can't gargle." And I say, "Well, we're going to have to try." And eventually people do. And not being able to gargle is another sign of it, of a low vagal tone.
It's not in the literature because it's such a difficult thing to measure. So that's why heart rate variability is the gold standard, so we always go back to that. But gargling is a really good way… and what I tend to say to people, if you can gargle as long as possible, and then spit it out.
Because most people can only gargle for a minute or two, and then that's it. And do that multiple times a day. And again, it's kind of tricky if you're at work, how are you going to do that when you've got to go to the bathroom and start gargling. But that's what they've got to do.
Andrew: You could do it at the pub, but it's not really congenial.
Emrys: Especially if you're doing it with the booze, yeah.
Andrew: With a beer.
Emrys: That's right. And then swallow.
Emrys: Yeah, so the other one is the gag reflex. Now I mean, I don't do this for everyone, but eliciting the gag reflex with a steel spoon or some sort of tongue depressor, if they have it available. It's not for everyone. A lot of people get really irritated by it, and it's not something that can be easily elicited in some people, so it's something... We start with the gargling, and move to that maybe.
But it's quite...that can be very effective. It can be very effective from as far as a motor exercise, as far as an intervention.
Emrys: Another one that I do, which you don't read about very often but I think it's worth doing as an adjunct to the other ones, is just getting a little cotton tip and just lightly tickling...it sounds, again, another odd one, tickling just the outside of your ear canal. Not pushing it inside, but just outside of it. You know, a lot of people talk about, "Oh, I really like poking it in my ear," and I go, Oh, that's..." it's odd. We always used to think that's quite odd. Maybe that's because of the vagus nerve, is my presumption.
Emrys: Another thing I didn't mention is it actually increases dopamine levels in the brain because it activates the ventral tegmental area on functional MRIs, so dopamine levels go up as well. So, maybe that's another little...
Andrew: So that's why they like it.
Emrys: ...you know, they're getting a little dopamine relief. Maybe that's why...
Andrew: Can we put up a diagram of this intervention up on the FX Medicine website? Have you got a diagram?
Emrys: Yeah, I can do that.
Andrew: Okay, great.
Emrys: Yeah, I can put that together and put it up for you.
Emrys: Oh, look, it's immense. It is, it's immense.
Emrys: If you go into ResearchGate, it's over 5,000.
Andrew: Oh, my God.
Andrew: So I was going to go into that, what kinds of research and evidence exists? I mean, I've just found three, and I'm going I...I've never looked for this. No way I've ever stumbled across this.
Emrys: So like I've already mentioned, you've got a lot in various different publications, Brain Stimulation, I mentioned Cephalgia, and Neurostimulation journals, they're all getting on board with this. The research that I've indicated, all of the stats that I'm talking about come from research, come from...a lot of them are using heart rate variability as one of their ways of assessing the vagal tone as well. The research in that is pretty gold standard for me.
Then research into migraines is getting up there. Depression has pretty much...besides epilepsy, depression has the best research. And so if you go in and look at the numerous papers available, I can make sure your listeners...I can upload as many papers as you need.
Andrew: Yeah, beautiful.
Emrys: There's so many. And some of them even look at, as I said, like concentration changes of norepinephrine and serotonin and dopamine. But some also look at brain changes. So they look at the neuroplasticity effects, and which are hippocampal in most part, and some of them even look at how many… what the firing pattern of neurons, before and after.
So you'll see things like locus coeruleus neurons start spiking in their action potentials, and they'll go into burst firing, and that's needed for huge amounts of norepinephrine release. And I don't want people to think...you know, norepinephrine and noradrenaline, we'll call it “release” is not a negative when it comes to depression. It's in low levels, generally, in depression, so...
Andrew: It's low levels, yeah.
Emrys: Yeah. And it's not something that people need to worry about as far as the sympathetic response. That's like I said, sometimes norepinephrine is used in a positive light, not just to do with stress. It's also used for focus, it's used for, us to orientate our attention to something. And you see that with people with lower norepinephrine, they've just got this sort of… they're distracted, they're unable to focus, they've got brain fatigue, sometimes you could say that, brain fog. And that's in part due to the lower norepinephrine levels.
It can also be just the neural connectivity, and that's...it depends how you want to talk about it. If you want to talk about it on a neurochemical level or a neurocircuitry level, and they're a whole different group of scientists who are doing the research on either. So the more they talk to each other, the better those two bits of research groups are going to get together, the better our understanding, I find.
Andrew: You just perhaps cleared up something in my brain about the difference between SSRIs and SNRIs, the serotonin and noradrenaline reuptake inhibitors, which obviously keep the noradrenaline there because their reuptake is inhibited.
Emrys: That's right.
Andrew: Yeah. So, that's really interesting to me. So...
Emrys: They are effective, but they have got problems as well.
Andrew: Oh, yeah.
Emrys: Like, a lot of people aren’t... yeah.
Andrew: Absolutely. So you've mentioned depression, you've mentioned migraine, cluster headaches, even autism, and certainly neuropathic pain. What other conditions might be helped by transcutaneous vagal stimulation?
Emrys: Okay, so there's been some research done on changes in heart rhythm, so people who have got atrial fibrillation have demonstrated resolution of the atrial fibrillation after vagus nerve stimulation. And that's also reflected in their heart rate variability levels as well, that coincides there.
I've been treating a lot of people with atrial fibrillation, and in most of the cases I've asked… and a lot of them are idiopathic, they don't really know why, or there's just maybe the doctor's said “Keep on these blood thinners,” or whatever the actual intervention they've got, but they're not...they've still got it, right?
And you know, it's only on a clinical anecdotal level, but everyone's having success. Everyone’s like...or they're...they don't get any spikes, it's well regulated, and it stays that way. I find that people... I had one girl, it was a very interesting case, every time she went to bed, her heart would race. She was a friend of mine, it was really early in my use of vagus nerve, and I said “All right, well let's try to stimulate it and see what happens.”
So we did it, and it improved the first time. The second time we did it, which was about a week later...and she'd been experiencing this for weeks and we didn't know why, and the doctors didn't know either. And we did it again, and it completely diminished to it didn't exist anymore.
Emrys: And a few weeks later, it slowly crept back, we did another session, and it hasn't come back since. That was months ago now. And that's one example of where you don't really know why it's there, they can't really find a reason. I mean, I'm sure if you look deeper, you go to other specialists and you'll find a reason why it's happening.
But just a little, novel treatment like that can have a huge effect on heart rhythm. And not in a negative way like people may presume. Like, there's a lot of talk out there about some vagal nerve stimulators having a negative effect on heart rhythm. But there's not credible evidence of that, and it's not consistent. And it's certainly, if it is occurring, it will happen with the implanted device.
Andrew: Yeah. Yeah.
Emrys: And that's partly because it's the lack of control over the stimulation. And it depends on the device you have as well.
Emrys: So, psoriasis is not really obvious in the literature, but the links between gut inflammation and psoriasis are there. I've been treating a range of patients with psoriasis in conjunction with Ananda, and we're getting fantastic results. I mean, I don't only use vagus nerve stimulation, that's something… I haven't even talked about the other therapies I do with photobiomodulation and intracranial low-level laser.
But using a low-level laser in conjunction with vagus nerve stimulation is far more effective than one alone. So it's important that with skin conditions, for me, I don't just use vagus nerve stimulation. But you can, and you'll still get an effect. It's just that if you can do a skin intervention, direct skin intervention with the low-intensity laser, and an anti-inflammatory effect on the body, it's the effect overall. Because you're working from the inside out, and the outside in.
Andrew: Yeah. But the vagal nerve stimulation with the low-light laser, that's not...
Emrys: No, that's not for the vagus nerve.
Andrew: Oh, right. Forgive me. Yeah, I was just thinking...
Emrys: So you can use that directly on the lesions on the skin right for the psoriasis, and we also use it for depression. So, low-level laser is used on areas of the brain that are less active in depression. The difficulty with low-level laser on the head is that you've got to get through the cranium. And it does work, it gets through, but you've got to put a large amount of energy in to get a small amount of energy onto the cortex.
Emrys: And that's showing really promising results in the research. It's not quite at its fullest yet, in as far as how vagus nerve is, but I've found it incredibly effective. So I use the both of them together because I may as well. I may as well be more effective overall.
Emrys: Yeah. So, there's a lot of conjecture in the literature about it. So we don't know the exact number. We think it's somewhere between two and four joules on the cortex, or 60 joules being applied. There's a lot of lasers being used out there that their quality isn't quite up to the level that we'd want them to be, and so we don't know whether they're accurate as far as how many joules they're using. So the parameters are a bit vague, but there is definite change as far as the analysis of depression symptoms.
The issue is also, the interesting things we see with vagus nerve stimulation and its difficulties are getting patients to understand the importance of it, and understanding “Why am I working on the ear to affect these other areas?” It's conceptually very difficult. And to teach someone in five minutes how their nervous system works, and how an afferent in the ear can be an efferent in the gut, you can't really… it's very difficult for people to get that, and how the ear's treatment is going to affect their depression symptoms. I've worked pretty hard on getting the wording right with them, and in most part, 99% of the time, people are right on board.
Emrys: Because people want another option, you know? And it's a novel way. It's a very non-invasive… it's not going to make them feel like they're doing something that's dangerous, that could be potentially harmful or anything because it's so innocuous, a couple of needles in the ear.
The hard thing is getting the right dose. You can't be in every day getting vagus nerve stimulation. Well you can, but it's not really affordable.
Andrew: Yeah. No, no, it's not practical.
Emrys: So for me, generally speaking, a couple of times a week is good. And then once you get stable, once a week. Then it's like anything, every few weeks, and then to the point where your vagus nerve is very active and you can maintain it with the gargling and things like that.
Andrew: Yeah. And you know, I get that... We covered the issues with the clip that I mentioned before. But could it get to a stage where people, because of affordability or preference for home treatment, that they become trained enough to be able to use that clip device?
Emrys: Yes. So in America, there's patents pending...not patents pending, rather there are certain products that are about to be released that are take-home devices. Some of them are medically prescribed, some of them are not. Some of them report...one's called Nerveana, and it actually is this little earbud that you can play music and at the same time get electrical stimulation.
Emrys: And it actually is...they say that it gives you the feeling of nirvana, you know, so it actually gives you this sort of euphoric sensation. And that's been approved for sale.
Emrys: That's one stimulator, but that's a very marketed one, it's not very medical.
Andrew: Yeah. Yeah.
Emrys: In Europe and in America there's also handheld devices that are placed on the neck, some are also placed on the ear. The ones on the ear are tricky just because of the shape of the ear, the handheld ones are easier. And a lot of the research is done with those.
Emrys: Yeah, so that'll eventually get to Australia. I'm trying to acquire some of them. It's just too difficult at the moment.
Emrys: But eventually, you will be able to do it from home. Which is ideal because most of these stimulators are not too intensive, so you can get a good response if you do it for a long period of time. It's like going to the gym, you can go once and not really get much of an effect, but if you go over the course of months, you get a big effect.
Andrew: Yeah, that's right. Yeah.
Emrys: And that's how you have to look at it. Yeah.
Emrys: That was me at the start, when I first started looking into it. Yeah.
Andrew: Well, I've got to say, you must have been sitting there blinking a bit. That's...
Emrys: I know, it's too good to be true. I thought it was too good to be true. I really did. But the paper upon paper upon paper...and I've been talking to a lot of the researchers, and they're really excited. It's like they're really...it's like, we've got something here. This is, like, the future of medicine, and with a lot of areas.
Emrys: And it's just we have to refine it and perfect it.
Emrys: A lot of them are nearly really there. Like with depression, and it's like with transcranial magnetic stimulation, a lot of people have heard of it, and a lot of people don't get it. But it's really effective. That's another therapy for depression.
There's a lot of things out there that are not drug therapies that are really effective. And I think that the more of these we have, the more options there are for patients, and then as far as, they don't just have to fall into drug therapy alone.
Andrew: Yeah. Well look, I think, particularly with something like recalcitrant depression, which is a real issue, even if this was an adjunct...you know? I mean, obviously, severe depression should be medically managed, and particularly if they've got suicidal ideation, but…
Andrew: …even if this was an adjunct for these people, then perfect.
Emrys: Yes, exactly. And then there are some anxiolytic effects as well, but the research is new in that area.
Emrys: I mean, I've got a few patients who have anxiety as well, and they always report... I mean, I'm not saying it's an anxiolytic, I'm just saying that they always report a decrease in their anxiety.
Emrys: So that's seen clinically, and I'm not trying to treat that. I'm normally treating another condition.
Andrew: Yeah. But well, what's...
Emrys: Normally you'll see a lot of anxiety with chronic pain and stuff like that.
Andrew: Yeah. For sure.
Emrys: So I might be treating, like, fibromyalgia or any number of different chronic pain conditions, and yeah, they'll start talking about the symptoms they have that are changing.
So I think fibromyalgia's an interesting one because of a lot of them having gut problems, anxiety, depression, and the chronic pain. I think it's not been researched properly with vagus nerve stimulation, but it's a really...it's an exciting area that could bloom into something really cool. Really cool, yeah.
Emrys: Yes. So at the moment, I'm doing trainings in Brisbane for my methodology. I'm not pretending to do anything that's in the papers, that they're using these different types of stimulators, it's using very simple means.
But I do a range of examination, testing, and history, and retesting procedures. Also understanding how to manually work on the vagus nerve, having talked about some of the manual work you can do on it with your hands to manipulate the nerve.
But the electrical stimulation, I've been doing some training, and I'm looking to do some training in Melbourne for clinicians. At the moment because I'm a musculoskeletal therapist and myotherapist, I've really been targeting those groups of people. But the hard thing is because you're using needles, and all your musculoskeletal and myotherapists are trained in needles, needle work, so dry needling, they're covered with that. So it's not a problem. But when it comes to things like naturopathy and nutrition, they aren't covered for that kind of work.
Andrew: No, no. No, that's right.
Emrys: So it's either that you have to have that certain qualification that allows you to be able to do it, do the training and further, or... And what I tend to do is the first day I'll do it on all that stuff you can do that's not interventional. Or it's exercises and understanding it better, and how you can work with it without getting into using the skills that I'm talking about.
Then the next day is about that. And so I find that, you know, I've had naturopaths come in and learn about it on the first day, and musculoskeletal therapists, and then the musculoskeletal therapists will stay for the second. And you know, you can...if you find someone who's been doing it, get in a referral program with them, and work with these conditions together. I think it's better that you don't just do this by itself. I always think working teams is better.
Athletic and physical health is a multi-modal approach to most conditions, so we have the naturopath and myself, Ananada and myself working on most things together. So, we find that more effective. And I know that a lot of people don't have that luxury, but I can highly recommend that you do that. I can give you some information about potential upcoming dates...
Andrew: Yes, please.
Emrys: Yep, we'll look at that.
Andrew: Yes, please. So, how soon are we looking at, can I ask?
Emrys: Hopefully by the end of the year, or the beginning of next year.
Andrew: Right. Okay.
Emrys: Yeah, and I'm looking potentially Adelaide, but Sydney and Melbourne. It just depends on the interest. So at the moment, if some of your listeners are interested in coming for the first part, if they’re naturopathic or nutrition or whatever, that would well suit them and they can get a lot out of it.
And the next day if someone's already got...even if people have got acupuncture as their background, because they've got training with needles and electrostimulations all the time, they can get in on this as well. So...yeah.
Andrew: Yeah. So, what's the website again, where they can look at further information and the dates of available times?
Emrys: And just look up the tab for training. Yeah.
Andrew: Great. So, we'll put that website up on the FX Medicine website...
Andrew: ...so that practitioners can access that. And yeah, look forward to seeing what the further revelations of researchare in this area... This is really exciting. This is really quite unique.
Emrys: Yeah. Well, we'll post up a fair amount of them, and then people can have a look through and make their own judgment on them, and so on. But it's extremely exciting, and it's interesting how many different conditions have been affected by vagus nerve being activated. And it might indicate a big part of a lot of chronic conditions, and why we need to add this in as another therapy in the treatment and management of a lot of chronic problems.
Andrew: Absolutely awesome. Emrys, thank you so much for joining us at FX Medicine today. This is really quite mind-blowing to me. I'm quite stunned. I look forward to seeing what revelations there are in the future. I really, really look forward to hearing from you again.
Emrys: Great. Thanks, Andrew.
Andrew: This is FX Medicine, and I'm Andrew Whitfield-Cook.
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