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Yeah, physician (pathologist, specifcally) with a degree in physics here. I'm going through articles in other tabs right now just because I'm skeptical enough to consider crazy ideas (always good to build bulwarks), this is, at best hypothetical, but mainly the chain of causality in the above statements is a hot mess.

I spend a lot of time looking at cell membranes. More than almost all of humanity. The naive Fluid Mosaic Model is certainly incomplete, but let's let Dr. Nicholson himself (the author of the original description) have a chance to provide his update first (1). So, yes, there's lot of other stuff going on, but certainly the basic organizing concepts are intact.

I'll allow the idea that the transfer of ions across the membrane is a thermodynamic effect. Of course it is. The whole nitrogen vs helium thing works well enough in my mind with just "thermodynamics". Yeah, sure.

But this statement "The action potential itself is the propagation of this solid phase" does not pass the sniff test for me. The action potential is a self-propagating electric field tripping channels along the way, propagating along inner and outer surfaces of the membrane, the channels are what make it self-propagating. Nothing about the concept of "solid" makes sense at these scales in a biological system. Everything is just more or less bound, and that neighbor-to-neighbor binding is entirely secondary to the mammoth electrical field whipping down the axon.

(1) Nicholson GL, de Mattos GF. A Brief Introduction to Some Aspects of the Fluid–Mosaic Model of Cell Membrane Structure and Its Importance in Membrane Lipid Replacement. 2021. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8708848/

Yes, this is a contested theory, but it's not a crackpot theory. I'm well aware of the fluid mosaic model. It is not mutually exclusive with what I've described, in fact it's the base from which this theory is formed. And it is not my theory, but the theory first formulated by literally the guy that discovered the mechanism of action of myelinated action potentials (Ichiji Tasaki, who worked on it during his entire time at the NIH). Call it crackpot if you want but please don't do so just because you've misinterpreted a a short forum post trying to introduce a complex concept in a concise way.

To clear it up for you, the transfer of ions across the membrane by ion channels is not something I'm debating. Nor am I saying that the electrical field isn't required for the action potential to propagate. If you took that away from my post I can understand you thinking it's crackpottery. I'm just saying it's not the whole picture. 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 to be pedantic) state that propagates with/as the action potential.

All these things are happening together, and more (like, how the lateral pressure profile might link the lipid state to ion channel conformational changes, etc). Simple electrical models cannot explain reversible uptake and release of heat (resistance cannot do this) with the passing of the action potential. Nor the reason atmospheric pressure changes dosage, nor the reason there's a change in optical birefringence and scattering. So you know what it describes is not the full picture. But don't take my word for it, go read Tasaki or Heimburg's work on this if you want to understand the detail. http://erewhon.superkuh.com/library/Neuroscience/Lipid%20Mem...

Mm-hmm, Mm-hmm... Oh! Oh, yeah... mm, mm. Mmm!

I know some of these words!*

More seriously - thanks for that description! It's always interesting to see just how many "principles" &/ "laws" etc. (our compartmentalized / simplified models) underlie certain kinds of physical behavior (and, sort of, emergent properties thereof). Even just sticking together enough of the simplest models can be kind of surprising and not so easy to reason about / handle with much "facility".

I've never learned much about anesthesia, and the little bits I have learned, here and there - and usually only in very specific contexts, makes it so most of this info doesn't really stick in my head. So, I appreciate getting a bit of refresher / learning every now and again. Particularly, in how it ties together with everything else involved.

Thanks!

* https://youtu.be/sl2W85KKzgc

Worth noting that, while this model has been around for a few decades, it does not have many adherents among neuroscientists. Which is not to say that it is wrong necessarily, just that I wouldn't want readers to get the wrong idea that this is a consensus view.

neuroscientists are just mad that "gut feeling" is actually the truth, and we're generally being manipulated by the billions of microbes in our guts. Simple example: why do people crave cake when they're on a diet that doesn't allow cake? There are microbes that convert stuff in grasses (corn, etc) into opioids. Opioids are great, make us feel great, and if we are used to having opioids and suddenly stop, we go into opioid withdrawal.

I haven't really put a fine point on the grand theory of gut-mind-body interaction, but i'm fairly certain that nearly every disorder or disease that isn't external (like radiation or malaria) will eventually be traced back to gut flora, from auto-immune disorders to depression.

Cake does not generally contain grasses...and if it were true that there were trains of gut flora that converted sugars to opioids almost everyone in America would live in a perpetual state of intoxication. Sugar withdrawal is also not even remotely similar to opioid withdrawal.

Cake usually contains flour, which is made from wheat, which is a form of grass...

No, wheat is made from the seeds, i.e., the grain, of wheatgrass, not the grass.

That some bacteria are able to eat the cellulose or other cells in grass is absolutely unrelated to their ability to consume the completely different structures and nutrients in a seed.

sugar is a grass, or corn syrup, which is from a grass...

edit: also opiate and opioid are different, i'm talking about the brain chemical, not the drug.

Once you're refining specifically sugarcane down to just sugar, "stuff in grasses" is a really confusing way to describe it. And it's not even right with corn, where the starch has to be chemically altered first.

If you're going to say something silly like sugar is a grass it's clear you don't know what you're talking about and I'm going to leave this conversation.

Most sugar in the U.S. is made from beets, which are not a grass.

Also...dark chocolate, soy, spinach, fruit, meat, and coffee are opiate triggers, so if sugar is bad because it triggers an opiate response, so is most of the human diet. It turns out the bodies response to eating...is to trigger an opiate response.

>Sugar cane production Sugar cane is a grass native to Asia and grows mostly in tropical and subtropical areas. In terms of the U.S. sugar cane production by state, it is mainly concentrated in the federal states of Florida, Louisiana, Texas and Hawaii. In 2021, Florida produced around 17.3 million tons of sugar cane and was expected to produce nearly the same quantity the following year. During this period, Florida accounted for more than half of the country’s total sugar cane production. Some nine hundred thousand acres of sugar cane are harvested yearly in the United States, generating over one billion U.S. dollars in annual revenues.

> Since the mid-2000s, sugarcane has accounted for between 40 and 45 percent of the total sugar produced domestically, and sugarbeets accounted for between 55 and 60 percent of production.

Sugar cane is a grass, and when i make a cake i use wheat flour and cane sugar.

I also know about sugar beets, but i specifically said "grasses". Saying that corn and sugar and wheat aren't grasses is hilarious. It doesn't matter what part we eat, as it's the gut flora that process it into the opioids, and they can't tell grass from the thing grass comes from.

Fukudome S.-I., Yoshikawa M. Opioid peptides derived from wheat gluten: Their isolation and characterization. Febs Lett. 1992;296:107–111. doi: 10.1016/0014-5793(92)80414-C. for example

Huh? Relevance? This has nothing to do with the biophysics of action potentials.

"neuroscientists" and the like go deep in the weeds with what/how different chemicals interact with cells, neurons, etc; but in general i don't read a lot of papers that try to answer "why". Scientists studied automobiles and discovered that applying pressure to a lever in the car causes the motion of the car to slow and possibly stop. End of paper, we proved cars stopped when we put pressure on a lever. No mention of friction anywhere.

I've been balking about this since at least 2006-2007 online and in person, and it took about a decade for studies that showed "why", not just "how/what". Then again, most people don't know that our bodies have dedicated receptors for nicotinoids, cannibinoids, opioids. Most people also don't know that tomato ketchup has nicotine in it, or that nearly all grasses contain the precursors to opioids in them. Once your intestines get a substance, nearly all bets are off as to what comes out, at what rate, and what volume.

So, essentially, that neuroscientists disagree isn't novel. They're laser focused on the post hoc, rather than the cause(s).

Are 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.

No, 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 - good overview paper, http://erewhon.superkuh.com/library/Neuroscience/Lipid%20Mem... - other papers/books on the subject.