Growing scientific interest in vagus nerve stimulation | Hacker News Reader

Growing scientific interest in vagus nerve stimulation

theguardian.com

274 pointsacallaghan148 comments

One of my children has severe epilepsy and has a Vagus Nerve Stimulation device implanted - Sentiva 1000

https://www.livanova.com/epilepsy-vnstherapy/en-gb/hcp/produ...

It has really helped although obviously it took surgery and then also nine months of slowly tweaking the settings.

Before the VNS they could (for example) not go on a trampoline for more than a few minutes without having a seizure, but now they're fine all day. They did still have seizures at night after the VNS but we tackled those with a different treatment.

The Sentiva 1000 sends regular soft pulses (for one minute every 3.5 minutes) and can also react to heart rate rising suddenly (which might mean a seizure) by automatically increasing its pulses. During a seizure if we want to manually activate the device we swipe over its location with a strong magnet and that activates it to send stronger pulses for a minute or so.

Batteries last about eight years. A few times a year we go to check the battery, the nurses have an ipad and a wand-type thing that they hold over the implants location, it uses some sort of low power NFC to read data and diagnostics from the implant. When we do need to change the battery that will be an operation. But less complicated than the initial operation (and even that was in-and-out in one day)

All pretty amazing.

This is so awesome - thanks for sharing this - my daughter also has epilepsy, but it is fortunately controlled by medication.

It seems that stimulating the vagus nerve resets something to default in the brainstem when a cascade event is about to occur - probably shuts down the errant signals from propagating to the entire brain ???.

Do you know which lobe in her brain it happens ??? (my daughter has left temporal lobe)

My child has Dravet syndrome so its quite major seizure activity and many different seizure types (tc, absence, focal, myoclonic). I think slightly more left lobe than right but its been a while since we had a full EEG. VNS is known to help with Dravet in enough cases that they were prepared to try the VNS.

The VNS can help stop seizures but also there's a sortof long-term effect from just having it firing every few minutes all the time, seems to re-train the brain in some way. I'm not sure if they really know how it works, just that it seems to help.

Another non-medication treatment that was very good for us was the ketogenic diet. Like, hardcore proper ketogenic diet, 4:1 ratio, prescribed and monitored by an NHS dietician. Every meal measured out by the gram. Its hard work but it did work very well. Its been properly researched - https://pubmed.ncbi.nlm.nih.gov/16146451/ https://pubmed.ncbi.nlm.nih.gov/25524846/ - for Dravet syndrome at least, keto is as effective as the best AEDs with fewer side effects.

Wow, I had no idea that the science around the vagus nerve had progressed so far that we actually have implants that can be used in humans. Amazing. I'm so happy it helps your child.

I was really skeptical that any of these nerve stimulation devices would work over a decade ago when the hype first started growing around them (among biotech investors, not the public). It just sounded way too good to be true but since then there have been a number of devices treating migraines and seizures that were previously intractable.

Really happy to be proven wrong!

> Can you provide more info about nerve stimulation devices treating migraines ?

https://www.gammacore.com/about/how-gammacore-works/

Note that vagus nerve implants were approved by FDA in 1997

Thanks for sharing. I'm considering VNS but frankly I'm terrified of complications and recovery time.

Operation was in-and-out of hospital in one day. Then had a big cellophane-like bandage on neck and shoulder area that had to be kept clean and air-tight for 2 weeks. It was a good bandage though, just had to patch it up occasionally with new layers of cellophane-stuff. Main possible complication would be infection (worse case is that device then has to be removed) or some people have side effect where it feels like their throat is ticked and they cough when device activates. We didn't have any problems.

Then once its all healed they turn the device using nfc wand thing and then slowly increase the power bit by bit over several months. There are various timing and frequency settings that can be experimented with.

This is really interesting!

I have struggled with an issue during meditation for several years now. I get to a certain point and it feels like my body/mind is going to relax, but instead I get this intense rising feeling up into the back of my throat, followed by an itching sensation that causes me to cough, and break out of the moment. Extremely frustrating!!

I wonder what is going on with my vagus nerve.

Here's a silly question: does your child feel the nerve stimulation when it happens?

Thats a good question not a silly one. They don't have the communication skills to tell me but they dont seem to be aware of it. Apparently some people experience it as a tingling sensation in throat or neck.

i wonder why the battery cant be charged wirelessly

Interesting idea. Current battery in the device (I looked it up) is:

Chemistry: Lithium carbon monofluoride

Voltage: 3.3 V, open circuit

Rated capacity: 1 Amp-hour

Self-discharge rate: <1% per year

Its a tiny non-rechargeable battery presumably carefully picked for safety and very slow usage over several years.

I suppose the main barrier to wireless charging of implant batteries would be heat - wireless charging generates heat. And when something goes wrong with wireless charging it can generate a lot of heat. So I guess its risky? But then surgery to change a battery is also a significant risk.

Also I guess someone would have to go through the long process with the FDA of getting it all approved, whereas (at a guess) people designing implants try and use already-proven components and techniques where they can to make approval more likely.

Could also just be a battery lifetime issue? 8 years is a long time. If they made it rechargeable, they might still need to replace it every 8 years anyway just for safety.

Heat would be an issue but if you do it a little bit at a time might be ok.

I've read that removing gluten from diets is apparently a way to reduce or stop seizures. Did you try this? Any information to share?

For me, the amazing thing about the Vagus nerve is that you can stimulate it with your breathing. And since the Vagus nerve affects the autonomic nervous system (involuntary, not consciously controlled) while breathing choices are conscious, this is one of the few ways that humans can directly impact important aspects of their psychology and physiology, like how calm they feel. Mindfulness + breath choices + vagus nerve => altered state. And that's why traditions including yoga and buddhism empathize breathing. Couple great books that touch on this are:

Breath: The New Science of a Lost Art https://www.amazon.com/Breath-New-Science-Lost-Art/dp/073521...

and

Altered Traits: Science Reveals How Meditation Changes Your Brain https://www.amazon.com/Altered-Traits-Science-Reveals-Medita...

A modern classic would be Holotropic Breathwork, developed by Stanislav Grof after the LSD based therapies he had been developing in the 1970s were made illegal. Yes, it sounds like hippie silliness. But it does have notable effects.

https://en.wikipedia.org/wiki/Stanislav_Grof

https://www.amazon.com/Holotropic-Breathwork-Self-Exploratio...

This might go beyond how you feel and into direct biological impacts. I don’t listen to the Huberman Lab podcast much these days but I did listen to the episode with David Linden, which I found quite interesting. [1] At one point, they are discussing the mind/body axis and the latest scientific developments in exploring how mental states can affect the body. There is a fascinating although very untested - but, testable - hypothesis that meditation may be able to slow the growth of cancerous tumours. The mechanism here is via nerve endings that reach the tumour and their effect on immune responses at the site.

Linden was emphatic about how science requires a mechanism of action, and that when people refer to this potential effect against cancer as due to “alignment of chakras” or whatever, it is “bullshit” to use his word.

I get where he’s coming from, but on the flip side, the benefits of meditative practice were arrived at long before science took any note of them. In fact for many years, the scientific perspective on it was that it was entirely bullshit. Meanwhile the people who were (admittedly incorrectly) talking about chakras were delivering real benefits to their followers. As such it seems to me that more respect is warranted, and perhaps even more caution. What do you think?

1 https://hubermanlab.com/dr-david-linden-life-death-and-the-n...

Well put.

I think these eastern concepts (e.g. meditation concepts such as chakras, "organs" in traditional chinese medicine) are not meant as objective truths, but rather as useful mental models. Different mental models used in the same culture often contradict one another, which only makes sense if you don't see them as ultimate truth.

Chakras are real so as Kundalini [0]. However, these aren't physical in nature, rather, they are on subtle body of consciousness. Now, that's not possible to prove scientifically yet, but with your dedicated regular practice, you can experience them yourself as this guy on HN did [1] which inspired me to start my own exploration (back in 2014) and have intense experiences which remains with me.

0: https://www.amazon.in/Kundalini-untold-story-Om-Swami/dp/818... 1: https://news.ycombinator.com/item?id=6910041

Haven't listened, but I think I understand where Linden was coming from, even if it's unnecessarily harsh. The idea that "you can breathe this way and get this effect" can be true and can come from folk wisdom, but they ascribe wrong reasoning to it which makes it mysticism. The reasoning is what's "bullshit". It's like saying "I tie my shoes tight every morning to honor the shoe gods or else they'll untie my laces." Well actually, you're right to tie your laces tight, but only because that's how laces work on a physical level.

The chakras thing, or any other mystical model, is only a low-resolution model. It's useful to point you to a correct belief, but we have to be careful not to get too invested in wrong reasoning. Or else you end up with a system of beliefs which may be mostly wrong - ie, "If my X chakra does this for me, I am sure my Y chakra does that for me," - when what you may be looking for is a completely different phenomenon.

> The chakras thing, or any other mystical model, is only a low-resolution model.

More importantly, they served their purpose continuing knowledge as both a practice and oral tradition such that they have survived millennia. This in spite of libraries burning down and the limited access to/absence of text, etc. I think in this lens, it's not right to condescend, or be confounded or annoyed that the mechanism still works today. Further to that, I think in absence of this instinct in the scientific community to condescend, the valuable knowledge preserved in mystical practices could be understood sooner

Well, it's a low-resolution model that ancient people converged on for a reason, which is that it is starts from a readily-attainable subjective experience, which is then used to explain things in ways that surely go too far.

It is relatively easy to feel some of your chakras, I've done it, it took about a week of effort via a hodgepodge of breathwork, stretching, yoga, and "somatic" meditation facilitated by THC. You try to awaken muscles all over the body, "unblocking" points of tension, and eventually you start to have this impression of "energy"/"heat" flowing in loops from points on the spine, out along muscles and back again; in my case "unblocking" some of these caused buried emotions to pour out, and temporarily gave me near-perfect posture. It's interesting: these are clearly a description of something real.

Octopus have enormous numbers of nerve bundles in their arms, such that when you account for them, they rival humans in computing power. I think our bodies work the same way. We hold intelligence in our whole bodies, not just our brains. You used your muscles to store knowledge that your brain couldn't handle.

> The idea that "you can breathe this way and get this effect"

You are not exercising when meditating, ergo your CO2 levels will drop.

I'd love to put a top meditator in a hyperbaric chamber and change the gas levels to something like CO2 @ 600ppm and then see how relaxed they are, unless they have high levels of myoglobin.

The higher the CO2 levels the more stimulated the body becomes. Its why some athlete's take a heaped teaspoon of sodium bicarbonate for asoda boost that has a stimulating effect on the body. Sodium causes the release of calcium from the bones which is stimulating, alters the metal profile in the blood, and the bicarbonate is double the CO2 which also stimulates the body and immune system. People who have trouble breathing used to be told to breath into a paper bag, as this increased the CO2 they rebreathed, which was useful when coal use was high.

So yes meditating can be relaxing, mainly because they are increasing oxygen levels in the body which is less stimulating than CO2 levels from running around.

The vagus nerve runs all the way down to the rectum in many animals, so be careful about stimulating it. One might have to suddenly evacuate in more ways than one, and this article seems like someone's idea of a joke, on the unprepared.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2952396/ Effects of autonomic nerve stimulation on colorectal motility in rats

https://pubmed.ncbi.nlm.nih.gov/15074355/ The role of the rectal branches of pelvic plexus in defecation and colonic motility in a canine model

I thought athletes used sodium bicarbonate to buffer the production of lactic acid during anaerobic activity. I've never heard of it as a stimulant. Can you provide a source for that mechanism?

Try it. Heaped teaspoon in a glass of water, give it 30mins. You'll notice the difference if you are walking around or doing more vigorous exercise like jogging or running.

Sodium/potassium kinase pump. https://www.ncbi.nlm.nih.gov/books/NBK537088/

Sodium - releases calcium, increases a chance of a heart attack. FYI! https://pubmed.ncbi.nlm.nih.gov/2158146/#:~:text=In%20respon....

CO2 levels. https://www.epa.gov/sites/default/files/2015-06/documents/co...

This is what you are referring to https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6544001/

There are other mechanisms, like the effect sodium has on adrenal gland.

It's just that there's so many people walking around with their shoes untied because they think the shoe gods are bullshit

A great point. That's also wrong reasoning and in this case more harmful.

It sounds like something I'd expect to read from Douglas Adams, i.e. the prehistoric person doing something, then the modern/scientific person telling everyone it's wrong until they discover the science behind it, then smugly telling people they're right now and they were right to be wrong before.

There's a whole different set of heuristics people develop when working with reasonings that might not be right but give a better outcome for whatever reason.

Scientific reasoning is a relatively new phenomenon on top of the old way.

Interestingly, scientific reasoning is getting so prevalent that people don't imagine the old way existed...

What is the specific “old way?” you are referring to?

> Linden was emphatic about how science requires a mechanism of action

I don't think this is correct. Science is based on empiricism. Of course we'd like to understand the mechanism of action, but it's not strictly required for scientific description of some aspect of reality. For example, Kepler's laws were derived from the observed paths of the planets — it was only later that these same laws could be explained with recourse to the theory of gravity.

Yeah, he likely meant "Nature" requires a mechanism of action.

Even if that is what he meant, I still don't think it's correct.

To speak of a "mechanism of action" is necessarily to speak about a model of Nature that you, an observer, have created.

Natural phenomena exist empirically and logically prior to any such model, thus is is metaphysically redundant to say that Nature as such requires a mechanism of action.

Meditation likely lowers stress levels which reduces cortisol levels which improves immune function/response to cancer. That’s a guess as to a mechanism.

I first learned about it when studying martial arts, years later science is just starting to realize how important it is.

Just by box breathing you can willfully lower your blood pressure and heart rate a good percentage (low double digits) with only a little practice.

>Breath: The New Science of a Lost Art

I'm a bit surprised that we don't have more criticism of this book. It was less of a pop science book, and more of an anecdotal gonzo journalism.

Nerve stimulation implants are really exciting. I have sleep apnea, and while I take to CPAP therapy pretty well, I hate having to travel with the device and I hate its limitations. When we travel, I have to ensure there's an outlet somewhere near my bed; I can't camp without a massive battery pack for my CPAP; I can't go backpacking; and even cuddling my wife at night is a challenge because of the hose hanging off my head.

There's now a sleep apnea implant available, which also functions based on nerve stimulation, and is apparently quite effective. It's still a bit large, so not ideal for those of us who can deal with a CPAP, but in another 10 years maybe I can stop using my CPAP and just get a relatively straightforward surgical procedure every 5-10 years. I'd absolutely do it.

Also using CPAP and cuddling is a big problem for me as well. I have to sleep facing the opposite direction because the venthole in the nasal mask I can tolerate (F&P Eson 2) blows on her face.

I use a Resmed P30i, which I find really comfortable, but if either of the tubes on the side of my head get compressed, it gets noiser, or if the vent at the top of the head is too close to a surface, which means I now sleep in pretty specific positions to avoid disturbing my wife.

Still, better than keeping her up with my incessant snoring, I guess.

Check eBay for medistrom batteries. I can get 1 night for AirSense 10 (w/o humidity); 2 nights using resmed portable cpap & no issues backpacking with the portable cpap so long as I can get a periodic recharge.

Depending on how severe your sleep apnea is, there are oral appliances that can help with mild to moderate cases of sleep apnea. Could be an alternative to a CPAP machine. It’s like wearing a bulky retainer at night.

That said, you’ll want to go to a dentist who specializes in sleep apnea and is able to test / fit the oral appliance properly. (Source: father is dentist who specializes in TMJ pain and sleep apnea).

I've heard they're about $3,500USD and aren't covered by insurance. For something that I'm unsure would solve the problem, it seems a bit much. If it were 1/10th the price, I would just try it.

Seems like the 3d scanning my kids had for their braces, plus 3D printing could make it less expensive, at least for a prototype device to just try.

I should try that "tape over the mouth" thing to see if it helps, particularly as I'm super mild apnea, but I'm expecting it won't really work with my beard.

That is correct on both counts: they’re a bit pricey and insurance won’t cover an oral appliance for sleep apnea, which is unfortunate!

I do tape over the mouth every night. It’s worth a try! I also wear an oral appliance to prevent teeth clenching at night which was a game changer for me in terms of jaw muscle inflammation (due to clenching).

Mouth taping is one thing my dad (dentist) recommends for people who snore. While I don’t snore or have sleep apnea, I do feel like I get a more restful sleep.

I have acid reflux and possibly a mild hiatal hernia. When it triggers in Just The Right Way, I also get severe panic attack symptoms.

When I started investigating it (my coping mechanism during panic attacks) I discovered that the vagus nerve travels next to the esophagus through the diaphragm.

So my complete layman explanation was that the stomach pushes through the diaphragm during a hiatal hernia -> it rubs against the vagus nerve -> panic attack symptoms.

I might need to add the study of vagus nerve to "why haven't we studied this about the human body more" -list along with gut bacteria composition.

I'm in a very similar situation as you with EoE, acid reflux, and a confirmed mild hiatal hernia. The anxiety seems to line up as well.

Have you found any additional solutions, past the standard PPI and diet for acid reflux?

Thanks!

Diet mostly, I dropped most added sugars, wheat and drip coffee (french press and cold press are fine for some reason) along with broccoli (random, right?) and industrial breads (something in the rising agents ¯\_(ツ)_/¯ ) and I'm currently mostly fine.

Large amounts of red meat is bad, because it just doesn't digest properly, I might burp in the evening and still taste my lunch sausage...

Metamizole is the only one that helps in the extreme cases (panic attacks), but luckily I don't get those anymore. I think I've had to take a single pill twice in the last 5 years. It's pretty much exactly 15 minutes from swallowing the pill and then all symptoms go away because it forces my diaphragm to relax and thus drop pressure to the vagus nerve.

> drip coffee (french press and cold press are fine for some reason)

That's so wild. If anything, you'd expect it to be the other way around, since French or cold press methods have the bean/grounds touch the water directly and therefore leave more oils in the final product, vs. drip coffee where it goes through a filter.

Hijacking your comment to share my story and ask for advice.

I have diagnosed EoE, I've had it for my whole life. I'm currently on 80mg omeprazole daily and an elimination diet. This helps a lot but is not a cure. I've also experienced benign heart palpitations for my whole life (confirmed by a cardiologist). For a long time, I've had a hunch that the two were connected.

On days when I have EoE flare-ups, I feel some pain and swelling in my esophagus, as though I have a bad chest cold. Food and liquids tend to linger in my esophagus for longer. Another unusual side effect is that, on days when my EoE flares up, I tend to experience frequent heart palpitations, most commonly right after consuming food or water.

Since the vagus nerve travels through the chest, adjacent to both the heart and the esophagus, I think the mechanism of action is this: the inflammation in my esophagus stimulates the vagus nerve, making a palpitation more likely. This inflammation also causes food and liquid to travel through the esophagus more slowly, which stimulates the vagus nerve further. The combined stimulus from inflammation and food or liquid can irritate the vagus nerve enough to cause heart palpitations.

Obviously I would like to cure both my EoE and palpitations, as they're currently the two biggest detriments to my quality of life. And inflammation due to an overactive immune system is the cause of EoE. So the possibility of reducing immune system inflammation just by stimulating the vagus nerve is very appealing to me.

If anyone reading this has an experience, opinion, research, suggestion, or anything they'd like to share, I'd love to hear it. I'm going to experiment with baking soda and famotidine to reduce inflammation, since I read in the above threads that either of those could work. But if there's some simple hack I can employ to reduce my symptoms (meditation/breathing technique, physical exercise, a stimulation device I can buy, some additional OTC medication I can take, etc), I love to hear it.

I haven’t been diagnosed with EoE (and don’t think I have it) but I do think there is a connection between heart palpitations and the digestive system. I have SIBO and will sometimes get them from the trapped gas.

Some would consider this as Roemheld syndrome, which isn’t an official diagnosis but I see it as more of an explanation that your digestive system can cause these symptoms, rather than there being a problem with your heart.

I don’t have any thing else to offer you as I’m not as familiar with EoE but you could look through the related subreddit to see if others have suggestions. Wishing you the best!

You may want to look into dupixent or mometasone for elimination of your EoE symptoms.

My daughter was diagnosed around 2 years old and has been seeing a doctor at Boston Children’s hospital who is involved in EoE research. For a few years now she has been taking a compounded mometasone slurry daily which has kept all her symptoms at bay.

Now that she is 12 she is eligible for dupixent which the doctor has said she has hundreds of patients on who are in total remission.

Thanks for the suggestion. I have an appointment with my GI coming up soon and I'll definitely ask her about those. Dupixent in particular looks very promising!

I'm glad you got your daughter into treatment early. I'm ~30 years old and research and treatments for EoE weren't nearly as good when I was her age, so I wasn't properly diagnosed until my 20s. By that point, just eating normal meals was a struggle and I had to have an esophageal dilation before I finally got onto my current treatment plan. I hope she never has to experience that, it sucks.

Omeprazole and elimination diet work ok for me, but it's not anything close to remission. I can finally eat normally again, but I don't have a comprehensive list of my trigger foods, and I get painful flare-ups if I accidentally eat the wrong thing. I'll gladly give myself injections once per week for the rest of my life if it means no more intermittent chest pain and it lets me eat a normal cake on my birthday again.

I can empathize with how difficult it must have been to get a diagnosis and treatment plan. In my daughters case her symptoms were coughing while eating and vomiting. Most of the doctors we saw at first suggested it was acid reflux and she should be on prilosec, but she continued to get sicker and sicker and we really had no idea what to feed her.

It turns out she is allergic to corn which is unfortunately in almost every manufactured food. We had to do a deep dive into corn and it's derivatives in order to avoid foods that would trigger her. Even things like citric acid can be triggers because of the way it is produced.

She's been doing great for a number of years on the mometasone and we are excited to start dupixent now that she is old enough.

I've been lurking HN for 14 years or so and never made an account but felt compelled after I read your comment because I know how tough EoE can be. Good luck with your treatment!

I’ve had recurring issues exactly like that for years. You have just given me something to look for (hiatal hernia) as that matches my symptoms.

Thanks!

I'm pretty sure I had a semi-severe case of hiatal hernia, but when the doctor shoved a camera down my throat to check, he actually fixed it by accidentally pushing the hernia down :D

Most of my worst symptoms went away after the checkup, but it took a LONG while for my digestive tract to fully heal. I couldn't burp at all for ... maybe two years, the pressure just stayed in my stomach. Drinking small amounts of fizzy drinks and rising on my toes + slamming my heels down got the air out sometimes.

There are still things I can't eat because they instantly irritate my reflux, buttery pastries being the worst ones.

It's interesting you say that, because since I had a camera shoved down my throat two years ago I haven't had symptoms until last week (I was ~35km into a 40km bike ride and it was a VERY sudden onset during a climb).

I'll talk to my GP this week when I see him.

Yeah, I've had this too. I've also noticed that digestion in my large intestine triggers panic attack symptoms sometimes.

I spent 6 years trying everything to solve reflux. I am a relatively fit 35 year old. I tried antacids, PPIs, H2 blockers and these just exacerbated the issue over time.

Eventually after much reading I read that without enough stomach acid, food backs up and causes reflux. It also causes the LES to not close properly. So I started taking Betain HCL and Digestive Enzymes (Solgar ones) before I eat and I can't tell you what a difference it's made. It's so amazing. I get 0 symptoms and I also feel so much better generally.

I honestly encourage you to try this. The medication for this stuff just has it the totally wrong way around. I can't believe this stuff is given out as one of the most commonly prescribed drugs in the UK at least.

Not GP but I also have severe reflux - I've had it years. It's been really bad lately.

In related information I've found that fortified yogurt helps not only my reflux but also improves my mood. But it never seemed to be enough to actually solve the reflux problem.

Just ordered the supplements. Truly hope this solves the problem.

Whoa I just realized that I have a hiatal hernia too. I didn't realize that's what that was. I hope this is a day of solutions!

I’d love to hear if this does solve it for you ! Feel free to reply on here or on my contact page : https://davidt.co.uk

I have a vague recollection that I was tested well over a decade ago and the result was that I have really mild stomach acid and/or not enough of it.

Basically if I eat stuff that digests slowly (fats and red meat), it takes my stomach a LONG time to actually break it down and move it forward. If I shove more stuff in there before it's done -> bad time.

I lost over 10kg during the worst episodes in about 9 months, I lived pretty much on rooibos tea (even green tea irritated my reflux), white rice and mildly flavored chicken.

Sounds really awful. Sorry to hear that! I wonder if this would have happened many years ago before modern agriculture and all the awful stuff that is present in our foods. I wonder if our environments are causing this lack of stomach acid / enzymes in people. This can’t surely have been happening when we were hunter / gatherers!

There are theories about how our modern wheat for example is vastly different from what it was 50+ years ago, something in the structure has changed so that there's "more" wheat, but it's just fluff - all the good stuff has been modified out to get the maximum weight of wheat at the cost of quality.

> This can’t surely have been happening when we were hunter / gatherers!

Or it did, and those people died and we no longer have any record of them. That's entirely possible, I suppose.

That implies might be a genetic disposition which would also imply anyone suffering today maybe shouldn’t be here if that mutation died out. I dunno, I’m a software engineer not a geneticist but I just enjoy the thought experiment

I'll have to try this! I have reflux or heartburn daily if I don't do things right. A few things help me.

1) Don't have an empty stomach. My stomach goes crazy. 2) Don't overeat. Large portions cause it nearly every time. 3) Don't eat anything within 2 hours of bed time.

So, basically, if I eat small meals often I am usually fine. And then there are trigger foods like too much coffee and alcohol and red sauces, and garlic and other things that cause indigestion.

I promise you, I had all this. If you try these supplements I mentioned you will never think about it again. The downside is you end up putting on some weight whilst you get over the fun of being able to eat whatever you want again :)

I know this sounds like a hack, but did you ever try taking some apple cider vinegar in water after eating? It's a lifesaver for me, near-instant cure for lack of stomach acid. Has to be the ACV "with mother", the cloudy stuff in it. Maybe no longer relevant if you're already taking Betain HCL (I thought that was a medication at first lol), but I definitely have to mention it in case you may have a natural medication-free alternative available that you may not have tried. Don't take my word for it or anything though, def read up on it if you're interested about it!

Yeah it’s the same mechanism ! The ACC stimulates the stomach to produce loads of acid and enzymes which it is lacking. The supplements I use are basically the same except the enzymes themselves are provided in the form of the digestive enzyme tablets and the Betail HCL with Pepsin is what stimulates the acid production!

Very glad it’s working for you :)

I use apple cider vinegar whenever I get acid reflux. It works but often only for about an hour. Perhaps I should start doing it proactively whenever I eat. How much water do you mix it with? I just take a tablespoon of concentrated vinegar.

I had symptoms of low stomach acid for a while also.

Six months into COVID I hadn't experienced anything at all on what would have been 1-2 monthly flare ups. Once I had the realization I put it all together.

When COVID hit I had restarted taking a multivitamin and some extra iodine (which is involved in stomach acid production, as it turns out). I had thought my diet was pretty healthy, but as it turns out there was something I wasn't getting enough of. I still don't know what. But I keep up with it and I don't have symptoms.

Wait until you hear about the research trying to find out if there's a connection between signalling molecules that bacteria release that affect the vagus nerve directly stimulating the brain to eat more junk food [1]

[1] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9102524/

Famotidine an old school H2 antihistamine used for acid reflux (pre PPIs), was found to have an additional mechanism of action via activation of the vagus nerve to inhibit pro-inflammatory cytokines in covid (via alpha 7 nicotinic acetylcholine receptor (α7nAChR) signal transduction - https://molmed.biomedcentral.com/articles/10.1186/s10020-022...).

It has also been used quite extensively to combat post-covid neuropsychiatric symptoms.

I think the link here is that increased LPS/endotoxin production by your microbiota can induce acid reflux, cause neuroinflammation and psychiatric symptoms. Low acid production itself can result in a more inflammatory microbiome further exacerbating the problem. Long term fix would be working on the migrating motor complex, improve motility/gastric emptying and rebalance the microbiome by reducing gram-negative bacteria/pathobionts and increasing butyrate production via selective feeding. [I'm not a doctor, this is just the direction I've been working on things myself]

That's interesting about famotidine. This is also a treatment for MCAS, which is probably under-diagnosed because it's kind of obscure and the diagnostic criteria kind of suck currently. It can reduce stomach acid, so my doctor and I decided against using it as the first option in treatment, but may reconsider even though the alternative seems to be working. Thanks for the link and explanation.

Can you share any relevant resources or ideas you've gotten on reducing the opportunists and increasing butyrate production? I've coaxed and cajoled my MMC and other digestive processes back into shape, or so it seems, but am struggling on the microbiome angle. It's tricky because the list of foods that trigger symptoms is insanely long, so it's hard to get creative and experimental as far as that goes.

Some people really do have mast cell issues, but everyone and their dog thinks they have MCAS these days and it's questionable in my opinion. Often a diagnosis will be based on whether any of the MCAS-drugs work (rather than testing which is very problematic for MCAS). But as you see in the linked paper famotidine was effective in mice genetically engineered without mast cells, so at least in that instance it's not a mast cell issue.

The tricky thing with increasing butyrate production is that everyone's gut dysbiosis is different - and therefore, a prebiotic that works for one person may make someone else's condition worse. For example, I have big blooms in my Prevotella Copri population which would consume Inulin and make my butyrate production worse - but in people without a Prevotella Copri overgrowth, Inulin would improve their butyrate production.

I would look into 16S microbiome testing (I use Biomesight) and use that as a guide, as well as slowly trialing interventions and monitoring symptoms. None of this is perfect and you kinda have to be on the bleeding edge of science/alternative medicine to figure things out.

Look into PHGG for increasing butyrate production

https://www.sciencedirect.com/science/article/pii/S175646462...

One thing that really helped me was just going to the gym. Basically strengthening my core improved my posture so that my esophagus isn't as crooked due to shitty posture.

I had years of dysbiosis type problems and found that the other main H2 blocker, Ranitidine, helped with my symptoms. Luckily I didn't take it that often or for too long, as it was found to be dangerously contaminated with a carcinogen when stored for too long. But that's not the point. The point is that an H2 blocker strangely offered relief.

I'm not a doctor or anything but you're describing gallstones and gallbladder attacks here. Regular panic attacks will reveal an emotional pattern. Gallbladder attacks usually happen after you eat a big, high-fat meal and won't have an associated emotional trigger.

It'll feel like a Tai Chi master is doing the Two Finger Death Touch on the right side of your diaphragm, but aside from that feels just like a panic attack.

The automatic feedback loop between heart and lungs is really cool. The more you slow your breathing the more you slow your heart. You are choosing to breathe slower via your vagus nerve. The heart responds accordingly.

By contrast the adrenal cortex, a little brain on top of the kidneys, automatically triggers fight or flight with threat detection. By the time you realize it your heart rate is already increasing. Breathing slowly, preferably through your nose, counteracts that physiological stress.

See also the last 100 years of research on the autonomic nervous system.

> One thing that makes the vagus nerves so attractive is surgical accessibility in the neck. “It is quite easy to implant some device that will try to stimulate them,” says Dr Benjamin Metcalfe at the University of Bath, who is studying how the body responds to electrical vagus nerve stimulation.

Did these (with supervision) during residency. As far as neurosurgeries go, fairly simple. You just have to be careful when you expose the vagus nerve as it lies between the carotid artery and the jugular vein.

This is in contrast to Deep Brain Stimulation which involves making a hole in the skull, exposing the brain, and inserting electrodes deep within the brain.

I did some work on DBS devices.

Yeah, that's an intense surgery.

The MD doing the implantation was a rockin' bitch-ass motherfucking stone cold killer. Sorry for all the curse words, but that's the best way to describe her. I've never been near someone so dead calm no matter what. Just ice in the veins. She was ~6'5" and wore 6" stilettos all the time. That surgeon had presence. I'd never want to meet her in a back alley late at night.

We were developing a new technique to help out with implantation. One of the hard parts of DBS is knowing where to leave the stimulating end of the electrodes. You want to hit a specific region, but as everyone's brain is different, there's no way to stereotype the process. We had a little optical sensor that we were trying to use to guide the electrodes and see differences in the neuronal density. The place you leave the electrodes is in an area of relatively high density (S. Nigra). Bunch of Fourier analysis, machine learning, and machine vision went into it.

ML for how to direct implantation, or the signals it produced?

I was working on a guiding fiber optic cable, so the signals were live during implantation. The fiber is then pulled out once the electrodes are in the correct position.

We used ML to help determine where the tip of the electrodes were in the brain. The received images needed a lot of processing (Fourier domain mostly), then ML against cadaver brains and other surgeries to help determine the position. Final say included a lot of test shocks to the patient and the surgeon's call.

The vagus nerve can also be stimulated by diaphragmatic breathing exercises and longer exhalations, see [1] and [2].

[1] https://www.psychologytoday.com/intl/blog/the-athletes-way/2...

[2] https://www.psychologytoday.com/intl/blog/the-athletes-way/2....

I feel down this rabbit hole after reading Breath by James Nestor. Got serious about practising 5.5 second inhales / exhales and started forcing myself to adjust to nose breathing (even during exercise)

It did a total number on my anxiety levels and pulled me out of the constant cortisol fuelled fight or flight mode I found myself as I slowly crashed and burned into the ground

I wish someone had taught me as a child, it would have made a marked difference on my life, I am sure of it.

Post the technique here so lazy people like me can read about it!

I think they're talking about box breathing:https://www.healthline.com/health/box-breathing

4s:Full breath in

4s:Hold

4s:Full breath out

4s:Hold*

*this one seems the least natural to me as you're just sitting there, at the bottom of an invisible pool, wasting away.

Interestingly Huberman talks about double breath in, then long breath out. https://www.youtube.com/watch?v=rBdhqBGqiMc

Highlighted in the book:

Nasal Breathing: Inhaling and exhaling through the nose to filter and humidify the air, increase oxygen uptake, and engage in diaphragmatic breathing.

Tummo Breathing: A Tibetan practice combining visualization and breath control, involving deep inhalations and exhalations to generate body heat.

Holotropic Breathwork: Rapid and deep breaths, usually accompanied by music, to achieve altered states of consciousness.

Buteyko Method: Focuses on shallow and reduced breathing to increase CO2 levels, promoting relaxation and better oxygen uptake.

Box Breathing: Inhaling, holding the breath, exhaling, and holding the breath again, all for an equal count, to calm the mind and increase focus.

Pranayama: Various yogic breathing techniques to control breath and energy, aiming to balance the body and mind.

Pursed Lip Breathing: Inhaling through the nose and exhaling slowly through pursed lips to improve lung function and control.

Sudarshan Kriya: A rhythmic breathing technique used in conjunction with meditation to reduce stress.

I teach a simplified breathing method for actors called "Flash Breathing" that teaches a series of breaths starting at the speed of gasping, ending at the speed of slow, deep breathing, and concentrating on the "space" between exhaling and inhaling. Very effective.

> 5.5 second inhales / exhales

> nose breathing

They did! Breathe in and out through your nose, spending 5.5 seconds each on inhale and exhale. This leads to taking the “optimal” 5.5 breaths per minute. Try to do this all the time but don’t experiment with new techniques when you’re driving a car or operating heavy machinery.

The book talks about all kinds of other stuff too but that’s the tl;dr.

I read the same book, and while it did help me in several respects (nasal breathing, mandibular and maxillar expansion via an orthodontic device, mouth taping), I only used its box breathing techniques under acute stress. It wasn't until I read a chapter in Peter Attia's Outlive about breathing techniques that I started changing my breathing in a way that, for me, feels like it's actively stimulating the vagus nerve. Here's how it works.

You want to breathe to expand your entire diaphragm, breathing into your upper and lower chest. One way to do this is to breathe through your nose slowly enough that you can't hear the sound of your own breathing.

To get a hang of it, lay on your back on a flat surface, place a hand on your stomach and a hand on your chest, and breathe in slowly. You should feel your stomach and chest rise evenly, neither too much in the stomach, nor too much in the chest.

Once you understand this feeling, you can practice it throughout your day. You feel your whole diaphragm expand, feeling the tension through your chest, stomach, and even expanding into your lower back. Anyways, that's how it's described in the book. I can say that since starting this breathing technique, I've felt a lot calmer. Best of luck, check the book out if you'd like a far more detailed and accurate explanation than mine.

There is also 10+ years research for tinnitus using Vagus Nerve Stimulation to stop it [1]. Results seem mixed. Many other drugs/neuro-stimuli for T have gotten mixed results and passed clinical trials such as Leniere only to flop in actual usage. It's interesting that the community anecdotal evidence such as r/tinnitus and TinnitusTalk are so useful for these cases because they are more likely to report negative results at the post-approval stage.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7951891/

I’ve got tinnitus and can’t really foresee any kind of solution. Not sure what the vagus nerve would do given the ears go straight in to the brain. Hopefully one day though, I’ve learned to live with it for the time being.

eeeeeeeeeeeeeeeeeeeeeee…

You don't need to buy a $750 USD device to do this either. You can get away with a very cheap TENS device that has ear clips such as:

https://www.tenspros.com/intensity-micro-combo-tens-microcur...

And then look at a study like https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7199464/table/T... to determine what settings to use for your condition.

Easier to read version of the study summaries:

https://docs.google.com/spreadsheets/d/1ibnJr6MqhHfpkXXzsKOD...

Part of me is interested, part of me is horrified by the idea of DIY electroshock therapy.

What exactly is DIY here? TENS devices are FDA approved and these are well known settings / protocols for different conditions.

DIY is "Do It Yourself" as in, not having trained professionals do it for you, therefore, the whole thing is DIY. Sure, maybe less DIY than making a pickaxe out of stone and mining the raw metals to build a tens device from actual scratch, but doing it to yourself is doing it yourself.

Yes you should absolutely talk to your doctor or an expert before doing it. But that doesn't make it "DIY". I was just pointing out that you don't have to buy a startup's expensive device to get the same functionality.

I have this dream scenario where they discover that the gentle swirling of a cotton swab in the ear canal stimulates the vagus nerve and has these tremendous health benefits, allowing the sanctimonious anti-cotton-swab-in-the-ear brigade to sit down and shut up for a minute.

Arnold’s nerve cough reflex: evidence for chronic cough as a sensory vagal neuropathy

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4222929/

Make those anti-eargasm prudes take a back seat for a while!

>Further research revealed that the brain communicates with the spleen – an organ that plays a critical role in the immune system – by sending electrical signals down the vagus nerve. These trigger the release of a chemical called acetylcholine that tells immune cells to switch off inflammation. Electrically stimulating the vagus nerve with an implanted device achieved the same feat.

One might also achieve comparable effects by drinking baking soda.

>"We think the cholinergic (acetylcholine) signals that we know mediate this anti-inflammatory response aren't coming directly from the vagal nerve innervating the spleen, but from the mesothelial cells that form these connections to the spleen," O'Connor says.

>While there is no known direct connection between the vagal nerve and the spleen -- and O'Connor and his team looked again for one -- the treatment also attenuates inflammation and disease severity in rheumatoid arthritis, researchers at the Feinstein Institute for Medical Research reported in 2016 in the journal Proceedings of the National Academy of Sciences.

O'Connor hopes drinking baking soda can one day produce similar results for people with autoimmune disease.

https://www.sciencedaily.com/releases/2018/04/180425093745.h...

Wow the baking soda thing is really interesting! You should add as a submission on HN. Thanks for sharing :)

Vagus nerve trauma is how liver shot KO's happen in striking arts. I always wondered how this worked. https://middleeasy.com/guides/dissecting-the-liver-shot/

Off and on, I've been seeing woo about the vagus nerve for a while. This article was refreshingly balanced. Now I know: "Tracey’s discovery also caught the attention of mind-body practitioners, including the Dutch motivational speaker and “Iceman” Wim Hof". Aha. Indeed.

Where is the rest of this stuff coming from? Is there a deeper dive?

Any mention of Wim Hof deserves a mention of the fact that the "Wim Hof Method" has a perfect verification mechanism: Wim Hof has a twin brother who does not practice the method and performs similarly well on most of the tests supposed to demonstrate the method's efficacy: https://news.ycombinator.com/item?id=24773331

In other words: there's likely a genetic factor at play much like no amount of training will give you the genetic advantage Phelps has in terms of wing span and lung capacity: https://www.nationalgeographic.com/science/article/olympic-g...

> similarly well on most of the tests

From your link they checked exactly one thing: shivering response to cold following breathing exercises. Both twins did exactly as well on this one test. That's not "most tests". It's one test. And personally, being able to withstand cold is the least interesting claimed benefit of breathing techniques.

Yes! And it's so easy to just try it and see for yourself. Laughable that anyone wouldn't just take ten minutes to see if it does anything.

What made me start paying attention to the vagus nerve noise was this: https://www.sciencedaily.com/releases/2020/08/200806092437.h...

This claims to improve language learning through selective non invasive stimulation.

The great confusion with these things is given how the body has a tendency to recalibrate dynamically to new stable levels of stimulation the trick would be finding what sort of on/off routine is needed to create the desired effect.

The article and comments don't mention it, but vagus stimulation by hot peppers (maybe wasabi too) has been studied and seems significant with respect to immune-nervous system interactions controlled by the vagus nerve, at least there's some interaction (wishful thinking perhaps, but as I like hot peppers this supports my view that they improve one's digestion and circulation):

(2013) "Capsaicin-sensitive vagal afferent neurons contribute to the detection of pathogenic bacterial colonization in the gut"

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4188534/

> "We conclude that activation of the afferent arm of the parasympathetic neuroimmune reflex by pathogenic bacteria in the gut is dependent on capsaicin sensitive vagal afferent neurons and that the release of inflammatory mediators into intestinal tissue can be directly sensed by these neurons."

More general current open-source review of the overall topic (2018):

"Vagus Nerve as Modulator of the Brain–Gut Axis in Psychiatric and Inflammatory Disorders"

https://www.frontiersin.org/articles/10.3389/fpsyt.2018.0004...

My dad has had deep brain stimulation (not the same as vagnus nerve stimulation, but in the same area) for over ten years. It helps a lot with his dystonia but he has developed severe paranoia which gets progressively worse. Of course you can't say that one caused the other, but I think it is reasonable to be cautious about devices that put electricity in your brain. Benefits are often instant side-effects may slowly accumulate over the years.

I'm all for folks expounding on the ways in which "current AI" sucks, but I have little patience for people who think that what it is now is all it will ever be.

Sure, it could be 6 months or 6 years before we see real improvements, but no one knows. No one knew that transformers were coming in the months before they arrived.

One thing that I think is encouraging is how fast computing power is increasing, along with languages, frameworks and models which allow you to make use of that power. I think that alone, even without AI, will result in world-changing advancements across many fields. The power to simulate large systems is growing rapidly and will enable prediction and discovery to achieve great societal benefits.

Years ago I read that breathing on your vagus nerve on your wrist can help calm you down. Each breath pulse would do something cause stimulation to calm you more like a feedback loop. I didn't know if it was bunk or not. I tried it but never felt any effect.

> Further research revealed that the brain communicates with the spleen – an organ that plays a critical role in the immune system – by sending electrical signals down the vagus nerve. These trigger the release of a chemical called acetylcholine that tells immune cells to switch off inflammation.

Isn’t inflammation an important process for healing? Too much is obviously bad, but if we go turning it off, won’t that lead to longer term issues?

Shouldn’t we be looking to solve what’s causing the inflammation in the first place?

I'm not a doctor so I won't pretend I understand how these treatments work but:

> Tracey immediately recognised the therapeutic implications, having spent years trying to develop better treatments for inflammatory conditions such as sepsis, arthritis and Crohn’s disease. Existing drugs dampen inflammation, but carry a risk of serious side effects. Here was a technique with the potential to switch off inflammation without the need for drugs.

I don't think anyone wants to switch off inflammation for everyone, all the time or as treatment for everything, but there's treatments where it's desired.

sepsis isn't an "inflammatory condition". It's a death sentence if it isn't dealt with promptly. Lumping that in with arthritis renders this meaningless.

Sepsis occurs when inflammations goes from being localized to being spread throughout your entire body. The bacterial infection is obviously the root of the problem, but it's the inflammation that actually kills. Being able to turn off that severe systemic inflammation might buy doctors precious hours or even days to successfully treat the infection before the patient's critical organ system shut down for good.

As laypeople, should probably take a beat before saying statements made by experts and medical researchers are "meaningless."

From google:

>Sepsis is a highly inflammatory disorder with the presence of organ dysfunction in severe cases and mostly caused by bacterial infection (Bone et al., 1989).

Not an answer to your question but a comment toward the quote:

In Traditional Chinese Medicine terms, the spleen has always been described as the cause of chronic inflammatory disease. "Spleen deficiency" the core feature of ulcerative colitis and arthritis f.e.

All sorts of medications inhibit inflammation because the body often goes apeshit and the “cure” becomes worse than the disease.

Having more control over it with simpler interventions would be a good thing.

> Shouldn’t we be looking to solve what’s causing the inflammation in the first place?

I agree with that theory, but so far we haven't been able to figure out what really causes many auto immune diseases or how to heal them. The current treatment methods involve nasty drugs that turn off parts of your immune system entirely, but also have various other side effects.

If we can adjust the inflammation threshold, we can fix the symptoms while we're looking to solve the underlying problem. Fixing chronic inflammation will probably take a few decades at least, until then I see no reason why we wouldn't treat the symptoms better, especially if it can be done with cheap and relatively non-invasive devices.

Great point, but VNS is not considered to be immuno-suppresant, it's immuno-modulatory.

So Vagus Nerve signals going to spleen really allows the body to more properly regulate inflammation.

There are a whole bunch of vagus nerve manipulations in current medicine. Many are quite common to self treat for things like converting episodes of SVT. Although the effectiveness is mixed. If they could find a non-drug treatment for Afib, I bet that would be big money based on the potential population and the current drug cocktail side effects.

Vagus nerve shenanigans always remind me of that whole NSA hack of side loading their custom hackey OS into things like embedded USB controllers or other little things on laptops that we never think about. Yea, it's not as flashy as interfacing w/ the CPU/system RAM directly but it could be useful....

I was a diagnosed with gastritis earlier this year. In the days leading up to my endoscopy, I had horrific reflux which was triggering anxiety. Putting an icepack on my chest to cool down the vagus nerve really helped with the angst and heart palpitations.

Does anyone here suffer from vasovagal syncope and has researched the topic more in depth? My last blackout was around one minute during a flight, house doctor says I shouldn’t be concerned.

Does anyone here have experience with any of the consumer stimulation devices like neuvana or sensate? Keen to hear your thoughts and if you actually use it?

So you are basicaly telling me than scientists found out that i can get some more alertness by slaping myself in the face?

Mine is very angry. It has caused me to die a few times.

This place is such a shithole in 2023. Absolutely no interest in anything of import, because that reality banging down your doors is too scary.

We’re in a revolution, nerds. Wake the fuck up.

You should consider the possibility that you're the one with a one-finger grasp on reality.

No U

I thought all the Hacker News "smarter than everyone else, self prescribers" were still endorsing Adderall, mild hallucinogens, and poop-swapping. But, by all means, shine on you crazy diamonds.

Is your comment intended to mock people who are interested in the vagus nerve, people who are interested in self-advocacy in the case of health problems, or just everyone on hacker news in general? Gotta specify, I'm not sure who I'm supposed to be looking down on here.

Reply on news.ycombinator.com