16 ms·
The anesthetic effect of air at atmospheric pressure
- sergioisidoro 3y agoWhat if instead it's helium that is a slight stimulant?
- jlawson 3y agoDo stimulants reduce reaction time? Waking someone up isn't the same as actually improving their performance.
- LoganDark 3y agoSome people can treat their ADHD using stimulants, and your reaction time tends to be better in that circumstance (citation needed though, I guess). IME, too much stimulants causes hyperreflexia, but I'm not sure if it's because of a decreased reaction time.
- AnotherGoodName 3y agoEssentially true by definition. If something is the norm then replacing that norm with helium and seeing enhanced performance isn't signal of the norm being restrictive. It's signal of helium being performance enhancing.
- adrian_b 3y agoThe effect of nitrogen varies with its pressure, i.e. with its concentration, while no changes are seen when the helium pressure is varied. This allows the conclusion that nitrogen has anesthetic effect and helium does not have stimulant effect. Because it appears that the anesthetic effect of inert gases depends on their molecular mass, being much stronger for heavy gases like xenon, it is possible that helium also has an anesthetic effect, but one that becomes noticeable only at higher pressures than can be safely tested.
- superkuh 3y agoThe action potential is an electrical manipulation of reversible abrupt phase changes in the lipid bilayer. Normally the lipid bilayer is in a liquid phase but the the switching out of monovalent sodium for bivalent calcium ions changes the number of phospholipid carboxyl head groups each ion is electrostatically associated with. This changes the heat capacity and causes the lipid membrane to become a solid/gel phase. The action potential itself is the propagation of this solid phase. This is how thermodynamics can effect neurons. And this is why dissolving gases into the lipid membrane, like nitrogen in the article, cause change the thermodynamic properties like the heat capacity and retard the solid phase a bit. Light gases increase liquidity. That's the anesthetic effect that reduces firing rates. And that's why local atmospheric pressure matters in gas anesthesia dosing. It's not that the old hogkin-huxley purely electrical circuit model is "wrong", it's a fine approximation of some effects. But it certainly can't explain the reversible uptake and release of heat during a passing action potential, nor the changes in birefringence and optical scattering, nor why nitrogen can act as an anesthetic like in this case.
- Robelius 3y agoAre you saying that what's happening is the permeability of the cell membrane changes with their physical states (from a scale of "more liquid" to "more solid")and that change impacts the transmission rate of the neurons? And an example of this would be an anesthesiologist putting you under is them making your cell membrane more solid to increase the resistance those neuron transmissions experience, just like adding more resistance to a circuit to reduce the voltage? Disclaimer that biological sciences aren't my strength so I'm just trying to understand what you're saying.
- superkuh 3y agoNo, it's not about ions going through the membrane or membrane pemeability. It is not about resistance to ions flow across the 10nm they travel perpendicular to the membrane. Transport of ions across through ion channels are required for the effect but the membrane itself (usually) is not leaking and I'm not talking about changes in leakage. It is about how the various ions like Na+ and Ca+2 associated with the membrane itself to change the membrane's physical properties. When there's lots of light gas anesthetic dissolved in the lipid membrane keeping the heat capacity low (disordered) it is thermodynamically harder (requires more energy) to form the organized 'solid' (actually more like a gel) state that propagates as the action potential. ref: https://arxiv.org/abs/1805.11481 https://arxiv.org/abs/1805.11481 - good overview paper, http://erewhon.superkuh.com/library/Neuroscience/Lipid%20Membrane/ http://erewhon.superkuh.com/library/Neuroscience/Lipid%20Mem... - other papers/books on the subject.
- mholm 3y agoA 10% increase in reaction time could be fairly significant in many sports. Could we start seeing football players, sprinters, or baseball players breathing from masks between plays?
- slau 3y agoWhile scuba diving, nitrogen narcosis stops the instant you ascend a bit (the typical recommendation is to reduce the ambient pressure by one atmosphere). I don’t think there is anything in this study that indicates the effect lasts more than a few minutes after exposure ceases.
- jjk166 3y agoDepending on exactly what one's doing, it's easily conceivable that the exposure can be concurrent with the activity. Maybe not football, where lugging around a compressed gas tank on the field is likely impractical if not dangerous, but a sport like Formula 1 or many E-sports would likely be quite conducive for an individual, and other sports like wrestling or swimming could probably be done entirely in a room with a modified atmosphere.
- ambicapter 3y agoI've always wondered if fighter pilots ever had a system to pump different gases into their masks whenever they encounter a high-stakes situation.
- MaxwellsDaemon 3y agoHere comes the juice!
- sebastiennight 3y agoCopeng - even the inyalowda scientists can't think properly on their own planet, sa sa ke?
- slau 3y agoJust completed my deep (40m/120ft) diver certification. A significant amount of the course was focused on nitrogen narcosis, and how to handle/detect it. Apparently, some divers will start feeling the narcotic effect between 20-30m. Beyond 30m, a significant amount of divers can feel the effects. Beyond 40m is the realm of tech diving, with trimix (helium/nitrogen/oxygen) or even heliox (helium/oxygen). I know nothing about this, so I’ll let others comment. The interesting thing about this research is that it sort of makes sense, and yet is very surprising. We’re basically continuously narked, we’re just so used to it we don’t even know. Fun fact: the exact cause of nitrogen narcosis is not exactly understood. It is most likely the fact that at higher partial pressures nitrogen is able to enter the fatty tissues surrounding our nerves. Except for helium, no other gas exists which does not have some form narcotic effect at higher pressures. Considering the prices of helium, this also explains why many deep divers are starting to consider rebreathers.
- killingtime74 3y agoI'm a certified Tech Diver if anyone has questions (TDI AN/DP & Heliox). Fun fact is the narcotic effect is very sudden for most people at a certain depth (30m for me) and also clears just as quickly. It's more pronounced if you are tired and/or the water is cold. Helium is very expensive like you say. Normal air fills are like $10 AUD, a tank of Trimix can be hundreds. https://www.scubadoctor.com.au/trimix-requested-mix.htm https://www.scubadoctor.com.au/trimix-requested-mix.htm. Normally you would need 3 or more 12L tanks filled with 240L of gas in each, depending on the dive. Most people who use it a lot do rebreather diving, where you can recycle a few liters over and over. The rebreather costs $10k AUD + training though and has many more parts that can fail. One is the oxygen sensor, that has limited lifespan and if it fails and you don't catch it quick enough can kill you (you switch over to bailout which is a backup gas supply).
- aaronscott 3y agoYour comment about being continuously narked reminded me how in early human history people relied on low-alcohol beer as a safe water supply. So back then it was a double-whammy. https://www.scientificamerican.com/article/the-conflicted-history-of-alcohol-in-western-civilization/ https://www.scientificamerican.com/article/the-conflicted-hi...
- jlawson 3y agoI wonder how much it would cost to fill my office with helium/oxygen mix to maximize my productivity. Would sound odd during calls, though!
- Terr_ 3y ago> Would sound odd during calls, though! I find myself thinking how you might dress or act to disguise it, and then this climactic (i.e. spoiler) scene from "Who Framed Roger Rabbit", and finally anxiety about the weird places my mind goes. https://www.youtube.com/watch?v=BDrqCq4fGRE&t=73s https://www.youtube.com/watch?v=BDrqCq4fGRE&t=73s
- gorkish 3y agoAlthough it's clear you are being facetious, let's see where it goes. I would surmise the best and most economical gas mix to breathe long term at ambient pressure would be somewhere between 80/20 and 75/25 mix of Argon/Oxygen.
- FreeFull 3y agoArgon wouldn't work, it has a stronger narcotic effect than Nitrogen
- deleted 3y ago[deleted]
- cwillu 3y agoI expect that the cost of the helium would dwarf the cost of of a fancy voice-shifting mic.
- LoganDark 3y agoJust curious, is this responsible for any of the effects of hyperventilation?
- FriedPickles 3y agoI wonder if there's a cheaper filler gas we could use besides He. Perhaps methane, hydrogen, or acetylene, though they're quite flammable.
- convolvatron 3y agoI don't know if you've ever taken a good whiff of acetylene, but I would hate to have to live off it (maybe is it truly odorless, and its just common contamination?)
- dragonwriter 3y agoMy understanding is that the characteristc smell of industrial acetylene is a result of sulfur compounds added as odorants (a common practice with odorless gases that create hazards, to make them noticeable.)
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- mrob 3y agoI wonder how pure oxygen (at low pressure to avoid toxicity) would work. There's still a substantial fire risk, as the Apollo 1 fire demonstrated, but unlike flammable filler gases it won't immediately kill you with a single spark. With a sufficiently fire-proof environment, and a full body fire-proof suit, maybe it could be done. EDIT: Although it seems the Apollo 1 fire happened with a pressurized oxygen atmosphere, not reduced pressure. Still, reduced pressure has its own dangers, because there could be sudden re-compression if the vacuum chamber failed. Re-compression barotrauma appears to be poorly studied (people don't usually work in partial vacuum). Or you could get crushed to death by the vacuum chamber imploding.
- ambicapter 3y agoApollo 1 was high pressure oxygen, since the capsule was still on earth, and they wanted to simulate the positive pressure difference between the inside of the capsule and space. In space it would have been low-pressure oxygen, just enough to satisfy human breathing requirements (so 0.19 atm).
- Luc 3y ago[1975]. Funny concluding paragraph: "Both theories of anesthetic action and the evidence cited in this report suggest that the nitrogen concentration in atmospheric air causes a measurable performance decrement in man, that the "nitrogen blanket" effect suggested by Miles[10] is a real phenomenon, and that human history has proceeded under partial narcosis. Perhaps this explains the current state of world affairs"
- hliyan 3y agoI hope this does not catch on. I worry about body hackers trying to live in a hermetically sealed homes with oxygen-noble-gas atmospheres.
- bottlepalm 3y agoSometimes I feel like the increasing carbon dioxide in the air is making us collectively dumber over time..
- anamexis 3y agoWell, it is. https://www.sciencedaily.com/releases/2020/04/200421090556.htm https://www.sciencedaily.com/releases/2020/04/200421090556.h...
- nichohel 3y agoTypo "signiGicant" in abstract.
- OliverTowers 3y agoThis could be an unfortunate oversight in an otherwise stellar document, but it biases me to question the entire outcome. If they can't even complete the abstract correctly, what other error is in this paper?
- deleted 3y ago[deleted]
- qwertyA 3y agoShould I move to the mountains to finish my phd?
- ejdanderson 3y agoDoes your PhD require increased reaction time?
- sideshowb 3y agoAnecdotally, as a mountaineer, I love the effect of a little less atmospheric pressure. Not loads less, above 3000m it starts getting inconvenient. But 1000-2000m my mind feels more clear and focused than at sea level. I wonder if this is related?
- pdc56 3y agoI've found this too, but assumed it was placebo. I lived at 6500' for a while - that was too high. The sweet spot for me is a particular mountain I go to which starts at 1200m and goes to 2000 (although I don't spend time at the peak - it's a ski field). Thanks for your anecdote, now I feel I can take my observations more seriously
- thehappypm 3y agoMount Washington?
- eastbound 3y agoIt could also be the sheer concentration of CO2. I work in a forest: 400ppm in the office every morning. Back at home, in the city, 5km away: 580ppm minimum all day long. Maybe cities make people stupid :D
- sideshowb 3y agoProbably not in my case, haven't measured co2 but I am lucky to live in a small village.
- mnw21cam 3y agoIt's incredible how quickly CO2 can build up inside a room. I'm also in a small village, and CO2 is 420ppm-ish outside. In my home office right now with the window open but no through flow, it's 1800ppm. If I close the window, it'll head off the scale of my CO2 monitor, above 5000ppm. Now that definitely is in the realm of cognitive impairment. I need some better ventilation.
- makeworld 3y agoAre there any historical relations to this? For example has nitrogen concentration varied across centuries? Or have innovations occured more frequently at higher altitudes?
- pdc56 3y agoHow many minutes until someone applies to YC with HaaS Co - Helium and facemask as a service subscription startup.
- crdrost 3y agoThis was roughly speaking my first thought as well. I thought "Well we always laughed at the sci-fi depictions of people with big cans of air for sale, come pay for premium filtered air ... but this is how that all starts, isn't it. Rich people pay for an air that might make them think 10% faster, then as it starts to normalize to the middle-class, they care less and less about pollutants in the air and eventually we just regard that as a poor-peoples' problem."
- RedShift1 3y agoWhat about the soothing effect of air at room temperature in the room temperature room?
- deleted 3y ago[deleted]
- That-Dude 3y agoIt concluded that the nitrogen in ambient air slightly but measurable impairs human performance compared with a non-anesthetic gas such as helium. This seems like a massive reach. Is it not possible the body is just perceiving that something is "wrong" about its current situation while breathing helium and is activating a threat response? The study authors didn't even bother to monitor heart rate, let alone blood concentrations of adrenalin and cortisol. This might have been a neat study in 1975 but it is not nearly rigorous enough.
- gumby 3y agoWhile anesthesia isn't particularly well understood, the thing that weirds me out is not the neurological mysteries, but that noble gasses like Xenon are anesthetics!
- koolba 3y agoIs that because they dilute anti-anesthesia gases?
- scotty79 3y agoWell, chemistry is not the only game in town. Physics can do things to bodies too.
- gumby 3y agoI assume you mean QM, but the noble gasses are distinguished by their lack of interaction.
- scotty79 3y agoOr just electromagnetism. They still take space and bounce around things. If somebody cut you with a jet of liquid helium you couldn't say, not fair, noble gases shouldn't interact with anything
- gdevenyi 3y agoSo is the suicide rate at higher elevations due to people being generally less doped up?
- Gravityloss 3y agoHow fast could you watch youtube videos if you switched to helium?
- firecall 3y ago> It concluded that the nitrogen in ambient air slightly but measurable impairs human performance So would a modified cabin air mix improve the performance of pilots?
- LeonB 3y agoLooks like they tested nitrogen-oxygen and helium-oxygen but not nitrogen-helium. I suggest they repeat the experiment with that control case and I can recommend numerous very suitable participants for that control group.
- readyplayernull 3y agoThat could explain this finding: > For every increase of 100 meters, suicide rates rise by 0.4 per 100,000 people. https://bigthink.com/health/altitude-suicide/ https://bigthink.com/health/altitude-suicide/
- haihaibye 3y ago9% decrease in response time would be pretty significant for gamers. Look out for LED illuminated gamer branded helium tanks.... and if you think online gamer chat is annoying now, wait until you get called a noob in a super high pitched voice.
- arthur2e5 3y agoNeon is allegedly non-narcotic too. Being closer to air density, it can be part of a non-funny-voice version of gamergas.
- nemacol 3y agoThe calming effect of being at the beach is enhanced by the elevation difference between my home and sea level?
- charles_f 3y agoWell and here I was, wondering what would become of all these oxygen bars they opened a few years ago and don't seem to last very long, they can sell helium-therapy now! Good for them!
- gooseyman 3y agoReminds me of Shadow Divers. IIRC they were instrumental in coming up with a breathing mix to counteract these effects https://www.amazon.com/Shadow-Divers-Adventure-Americans-Everything/dp/0739320831 https://www.amazon.com/Shadow-Divers-Adventure-Americans-Eve...
- nradov 3y agoShadow Divers is a good book, but the subjects were hardly the first to use helium mixes to counteract narcosis. That goes back to US military experiments in the 1920s.
- pmarreck 3y agoIs this why breathing pure O2 makes my head feel clearer?
- countWSS 3y agoHighly surprising mammals didn't adapt to this, aren't nitrogen levels the same for 100m years? Being 10% slower is actually a huge handicap, and seems to be something fishy with the idea we live permanently under influence without evolving something like biological counters. A rabbit that is 10% slower will face a huge evolutionary handicap.
- jamiek88 3y agoYeah but if everything else is also 10% slower does it matter?!
- wcoenen 3y agoFish evolved to swim effectively in water, but the viscosity of water still slows them down. Adapting to deal with a problem isn't the same as completely eliminating the problem.
- sinuhe69 3y agoPerhaps the little anesthetic effect also helps us to calm down and not being hyperactive all the time? I find thinking in diffuse mode and day-dreaming very beneficent.
- scotty79 3y agoAre there any rules against race car drivers breathing heliox?
- todd8 3y agoMy first, brief, dive to 135 feet (41m) was in 1976 off the coast of Cozumel. I was in a group led by a dive master and we quickly descended, swam through a large ring shaped coral structure at around 135ft, and started our ascent. More accurately, all but one of use started our ascent. Back then, of course, we had to rely on the Navy dive tables for maximum safe bottom time (just 10 min from entry at the surface to start of final assent), and we still added about 5 minutes at 15 feet as a safety stop before exiting the water. These limits, determined by the Navy for Navy divers are intended to prevent decompression sickness (the "bends"). Unrelated to the bends is another hazard, nitrogen narcosis that can interfere with clear thinking. It usually starts to affect people at around 150 feet and I barely noticed it at 135ft. However one diver in the group was affected and after passing through the coral archway continued to swim down the wall of coral toward the bottom at least 100ft deeper. The dive leader had to chase this diver, catch him, and then go though a real decompression stop or two with him on the way up. Now days, sport divers can explore these depths more safely by using a mix of nitrogen and oxygen called Nitrox which is a 65/35 percent mix of Nitrogen/Oxygen vs the atmospheric proportions of 78/21 percent. This lowers the partial pressure of Nitrogen while diving and thus allows safe diving at greater depths and duration for sport divers. If the research described by the featured article is true, this suggest a simple performance enhancer. Perhaps in the future, SAT exams will have to outlaw the use of Nitrox SCUBA tanks in the exam room.
- nradov 3y agoNitrox is any mix of nitrogen and oxygen. It isn't specifically 65/35; other mixes such as 68/32 and 50/50 are also common. Oxygen also seems to have a narcotic effect and so breathing nitrox doesn't significantly reduce narcosis. Thus breathing either nitrox or air below about 100 ft (30 m) isn't a good idea because it impairs your judgment and reaction time. Depending on the exact gas mix and depth, oxygen toxicity can also become a hazard. For deeper dives we add helium to reduce both problems, as well as to reduce work of breathing.
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- outsidetheparty 3y agoI'm just enjoying the image of wealthy mind-hackers filling their workspaces with a helium-oxygen atmosphere. Sure, they might be able to think nine percent faster, but will anyone take them seriously with their squeaky voices?
- sinuhe69 3y agoI wonder whether the little anesthetic effect of nitrogen also helps us to calm down and not being hyperactive all the time?! I find thinking in diffuse mode and day-dreaming very beneficent.