> Glanzman’s experiments — ... — involved giving mild electrical shocks to the marine snail Aplysia californica. Shocked snails learn to withdraw their delicate siphons and gills for nearly a minute as a defense when they subsequently receive a weak touch; snails that have not been shocked withdraw only briefly.
> Ryan knows Glanzman and trusts his work. He said he believes the data in the new paper. But he doesn’t think the behavior of the snails, or the cells, proves that RNA is transferring memories. He said he doesn’t understand how RNA, which works on a time scale of minutes to hours, could be causing memory recall that is almost instantaneous, or how RNA could connect numerous parts of the brain, like the auditory and visual systems, that are involved in more complex memories.
It sounds less like the standard definition of "memory", and more like RNA stores/caches the response mechanism of a pain receptor. Thoughts on that interpretation (I'm a layman on these subjects)?
I would argue there is no "standard definition of memory" as it relates to beings / consciousness / qualia.
Even if we limit "memory" to what people have when they reflect on past events.. we don't know /what/ that is; where it is stored, why it is so error prone, etc.
we also don't know much at all about the mechanism behind RNA; we have mapped some genes but afaik, the mechanism for how those sequences actually do anything at all, yet alone things in particular is a huge mystery.
It's interesting how most "skepticism" is exposed for what it truly is, that being unwarranted assumptions and semantics that prop up weak models of reality and block out better fitting ones.
Life force acts at the molecular level. There's a fifth fundamental force of nature, just like gravity/electromagnetic/strong/weak forces, which interacts with specially structured organic matter, like DNA or RNA, that act like antennas to that force.
Anyways that's just my theory and a lot of the skeptics, like the people downvoting this right now, have already made the assumption against it without testing it for some reason.
Science can and will eventually solve everything, including life itself, but we need people to believe in the scientific process.
> There's a fifth fundamental force of nature, just like gravity/electromagnetic/strong/weak forces, which interacts with specially structured organic matter
We can fairly confidently exclude this possibility. Dirac’s equation forbids it [1]. Or, in your specific language (which is good, don’t get me wrong): we have tested this hypothesis, countless times, and conclusively disproved it.
It's not a complete description; we haven't included the weak nuclear force, or couplings to hypothetical particles like the Higgs boson.
The article literally states that Dirac's equation is incomplete at modeling the full situation.
But that's okay, since those are only important at high energies and/or short distances, very far from the regime of relevance to the human brain.
And the article makes the mistake of assuming that life force is the physical driving energy, instead of electromagnetic energy itself being directed by a life force.
There are lots of randomness in quantum physics. The life force would cause that to be more deterministic. Einstein himself was a proponent of the hidden-variable theory, famously stating that "God does not play dice".
The article also states why that omission is irrelevant.
> And the article makes the mistake of assuming that life force is the physical driving energy
No, it’s simply a tautology: if it interacts with physical entities, it’s physical. EM radiation itself is a physical phenomenon, so it doesn’t provide a magical escape hatch. It doesn’t matter what you call this mystical force; by virtue of interacting with a physical system it must be subject to rules of physics, no special pleading can change that.
> There are lots of randomness in quantum physics
Yes, but that is provably a fundamental property of quantum systems, not something we can ignore or manipulate nilly-willy. Your Einstein quote predates relevant experiments that disprove this hypothesis. “Who are we to argue against Einstein?” is therefore a classical argument from authority: we are arguing based on evidence (and new theoretical underpinnings) that Einstein, at the time he uttered the phrase, didn’t possess (in particular, Bell’s theorem). Your objection is exactly like refusing to acknowledge relativity, saying “Who are we to argue against Newton?”
Anyway, if you’re keen on an argument from authority then consider this: who are you to argue against the consensus of the smartest minds working in the field of neurobiology? I hope you can appreciate how this argument sounds less convincing if used against you.
I don't know how you can be pretty sure about any of that, but I look forward to the faster-than-light signaling devices we can build from this new revelation about nature.
That’s irrelevant. These terms don’t mean anything in isolation. You just picked the two terms on the Wikipedia page on Bell’s theorem that allow you to escape the restrictions of quantum nondeterminism.
But you missed the fact that they don’t allow you to violate causality. In the context of our discussion this means that they cannot be used to circumvent quantum indeterminacy because that would break physical causality.
The idea that a life force can violate causality is based on the fact that theories on life/god/spirit center around infinity, and possibly related to the multiverse.
I keep telling you, it has been tested, and disproved — countless times. That’s what “contradicted by Dirac’s equation” means. If you insist on ignoring that evidence then, yes, you are absolutely ignoring physics.
There is no such thing as a test for life at the molecular level, we only describe it at the system level of a whole organism. Even then there is no hard and fast test because organisms exhibit such diverse ranges of behaviour.
For example the chemicals in cell cytoplasm seem to function identically outside a cell as they do inside one. In the first case they are not part of a living organism but in the latter case they are, but this does not appear to make any difference to their properties or characteristics. What difference would you expect to see?
> How are nanobes & prions determined to have life?
They aren’t.
To quote: “No conclusive evidence exists that [nanobes] are, or are not, living organisms, so their classification is controversial.”
> Are there microscopic Turing tests?
No. That’s what we’re telling you. “Life” is not well-defined. The textbook definition you might have seen in school would misclassify fire as alive.
For a fun take on this, look up the comedy podcast (starring Professor Brian Cox) called “The Infinite Monkey Cage”, specifically all the episodes which ask if a (freshly picked) strawberry is alive and if not when exactly did it die.
They aren’t.
To quote: “No conclusive evidence exists that [nanobes] are, or are not, living organisms, so their classification is controversial.”
You say nanobes aren't life, but then you say you don't know? Pick one.
“Life” is not well-defined. The textbook definition you might have seen in school would misclassify fire as alive.
Sorta pretentious to just define life to fit existing narratives when you don't have an explanation. We have to figure out more instead of stopping at what we don't understand.
> You say nanobes aren't life, but then you say you don't know? Pick one.
No, ben_w said that they “aren’t ‘determined to have life’”. That’s a very different statement.
But I’ll go out and say it: they aren’t life. Nobody is talking about nanobes any more. There is no research on nanobes in the life sciences. This is not a hyperbole, I mean that the number of articles published on nanobes in over two decades is literally zero. No single lab in the whole world is researching them. The last scientific publication on the topic, from 2001, was a review concluding that there’s nothing to it.
They were an embarrassing mistake that briefly made headlines.
> Sorta pretentious to just define life to fit existing narratives when you don't have an explanation.
I’m having trouble understanding where you’re going with this sentence.
I’m not defining life, I’m saying there isn’t a definition of life (that I know of) which seems satisfactory.
Also, I don’t think it would be pretentious to start with a definition that fits existing narratives, because that’s how most words work: a label for a bunch of examples, followed by a rule — a definition — which creates a pattern for those examples. Like fire “metabolising” oxygen and fuel to reproduce and “move”, but not being alive. When you find edge cases, either change the definition to fit the new data or create a new category for the new data [1]. I know that domain experts don’t use that previous definition of life for exactly the reason I gave, but last I checked “are viruses alive?” still got arguments.
Also also, treating life as a fifth fundamental force of the universe when chemistry explains all the components just fine is… well, literally pretentious.
[1] That’s just an IMO about language, of course: if language was that simple then NLP would be a solved problem.
Also also, treating life as a fifth fundamental force of the universe when chemistry explains all the components just fine is… well, literally pretentious.
No. Stating that chemistry explains all the components of life just fine is literally pretentious.
Maybe chemists should stop researching since they already explained everything?
Now you’re just nitpicking. So far every single process we have analysed occurring in living things has worked exactly as we expect from our understanding of chemistry. There just isn’t any reason to expect we will find anything chemistry can’t explain, and you haven’t given us any reason to do so or a way to test for such a thing.
To put it another way, what leads you to your conclusion? What evidence is it based on? What phenomena that we currently observe might such a thing explain, and how?
Whether or not those things are alive is a matter of debate, many scientists say that they exhibit some of the properties of living things but not all of them.
There are many web sites that discuss the properties of living things, I’ve linked a decent one below. It might be useful to think of it in terms of a ‘running’ engine. If I switch a running engine off, or it runs out of fuel, or someone breaks it with a hammer it stops running. Being alive for an organism is analogous to being in a ‘running’ state for an engine. It’s not an attribute of any individual components, but rather a description of the behaviour of the whole system.
> we also don't know much at all about the mechanism behind RNA
Wait wait wait. We know a tremendous amount about “the mechanism behind RNA”. Without being more specific it’s hard to say what you mean but we’ve certainly done a lot more than “mapped some genes”. We know pretty precisely how protein-coding genes get transcribed and translated, and how they effect changes in the cell (in general, if not in particular). There are open questions about specific catalytic functions of RNA but it’s certainly not a blank slate.
My thoughts exactly. Another problem with RNA is that it is a few orders of magnitude too slow (minutes versus fractions of a second) to account for memory formation. Which is not to say that gene expression is not involved in memory consolidation; that's been known for a long time.
Genetic storage is a form of "memory" generally speaking. Some state can be stored and transferred, obviously. It's okay to recognize that biological systems have multiple, diverse, and sometimes redundant subsystems operating simultaneously.
It could account for some amount of long term memory formation— or it could ‘color’ our memories in someway— associating them with pain or trauma— or happiness and joy.
There have been interesting animal experiments which perhaps avoid that eg
>Perhaps the most intriguing animal paper so far is a study published online in the winter of 2013 that appeared to show that fear memories can be inherited. Researchers from Emory University trained male mice to associate an odor with an electrical shock, so that they would get startled simply by smelling the odor by itself. Surprisingly, the scientists found that the smell also startled the next two generations of mice. https://www.vox.com/2014/8/18/5927269/epigenetics-definition...
Yes, by raising pups with surrogate parents. However, the study was criticised for other reasons (lack of statistical power, no explanatory mechanism) and, in the intervening years, nobody has successfully replicated this experiment.
This presupposes that the senior mouse, having been exposed, can describe both a particular smell and the appropriate response to a junior mouse. So I'd guess that's ruled out already.
No study has successfully shown that inherited PTSD actually exists in humans. The studies that purport to show so are plagued by flaws. Here’s a good write-up of the state of the field: https://www.theguardian.com/science/blog/2015/sep/11/why-im-... — this is from 2015 but it’s still current.
At any rate, RNA definitely doesn’t survive generations. It’s a short-lived molecule. Stable epigenetic marks modify the DNA, they don’t involve RNA (except as an intermediary).
Elizabeth Rosner isn’t a biologist, and (unintentionally, I’m sure) misrepresents the research. The majority view in the field of epigenetics is that trans-generational epigenetic inheritance of things like trauma currently lacks compelling evidence and, just as importantly, a plausible mechanism. The studies from Emory University and Mount Sinai, for instance, were widely panned (see article) for lack of controls, lack of mechanistic insight, and weak statistical analysis.
What little evidence there exists shows a very narrow range of effect in model animals. I’ve co-authored one such study that specifically shows the heritability of stress in mice. I can confidently say that this only works in very specific, artificially constrained instances, the evidence is tenuous, and mechanisms are elusive.
To clarify, this isn’t to say that trans-generational epigenetic inheritance doesn’t exist. Rather, we know that it does in specific circumstances (in particular in invertebrate models). But the claims by Rosner and in some of the more sensational (and flawed) papers require a big leap of faith that most scientists in the field aren’t willing to take, lacking evidence and a mechanistic explanation.
What’s more, none of the scenarios described by Rosner requires trans-generational epigenetic inheritance. It’s much easier explained by social/cultural transmission. Invoking epigenetics in this context is pseudoscience.
Regarding mechanisms, I was under the impression that DNA methylation was widely accepted as a primary mechanism for epigenetic inheritance. Not so much, or is that one of those artificial scenarios you referenced?
That’s correct but you’re (understandably) confusing “epigenetic inheritance” with “trans-generational epigenetic inheritance”.
The first (i.e. epigenetic inheritance, particularly via DNA methylation) is a ubiquitous biological process by which a state is encoded in the cell and can be passed down to daughter cells upon cell division. Hence the daughter cells inherit the mother cell’s state. At its simplest, it just acts like a “bookmark” in the genome which informs the cell what parts to read, and what parts to skip over.
But things are different when talking about multi-cellular organisms that pass heritable information through the germ line. This is what trans-generational refers to. For the longest time it was assumed that no epigenetic information could be transmitted through the germ line due to a concept known as the “Weismann barrier” (think of it as the librarian: upon return, she removes all the bookmarks from the books). We now know that, under specific circumstances, this barrier can be “violated”, and “leaks”. However, unlike normal (genetic) inheritance, this leak does not allow a structured transmission of information according to our current understanding (that is, a bit of information encoding a phenotype “A” wouldn’t necessarily cause the same phenotype in the offspring; it would simply lead a perturbation). There are more specific exceptions to this rule which, for instance in nematode worms, allow a more structured information transmission (though it’s an open question whether DNA methylation is causally implicated).
Thanks for that clarification. I wish the popular literature on the topic took similar pains to point this out. I can’t help but wonder if this is the root of much of the misguided interest in epigenetics.
> I can’t help but wonder if this is the root of much of the misguided interest in epigenetics.
In a word: yes. Even within the field this causes confusion (researchers of course know the distinction in principle, but the term “inheritance” is suggestive, and has led more than one person down the garden path). To make matters worse, “epigenetics” also can refer to several different things.
Currently in Ubud, Bali, so being exposed to lots of hippie bullshit (crystal reiki healing, anyone?). However, there's an idea floating around alternative medicine that human families can inherit trauma, and perhaps this is a mechanism for it? Seems more likely that the effect (if any) would be passed down through socialization, but food for thought.
Take a look at "Transgenerational epigenetic inheritance" (https://en.wikipedia.org/wiki/Transgenerational_epigenetic_i...) and at research into how epigenetic inheritance is cited as a mechanism for passing down trauma between generations. I read about malnutrition in world war II affecting several generations but I don't remember the source, and the Wikipedia article mentions the Dutch famine
Same caveat as above: the existing studies are deeply flawed. So far, the evidence for this kind of trans-generational inheritance is very week, and there’s no plausible mechanism to explain it, either.
I don't have access to the original paper right now, but Dave does do good stuff, he's no crank, and I'd believe him for the time being.
A possibility to what is occurring is that the RNA is 'interfering' somehow with the DNA synthesis. The synapse is very tightly regulated and getting receptors/transmitters into it may be affected by the production of the proteins in the first place (or the 'state' of the receptors, ie actelyation, methylation, etc). Under this idea, a memory is just the memristive state of the synapse, controlled by the populations of transmitters and receptors (all occurring in a network of neurons and synapses). The RNA may be affecting that downstream network during the DNA>RNA phase. But, I've not read the paper and seen their controls yet. I'd assume Dave really went all out on the controls.
I'm a mammalian/zebrafish guy, and my snail anatomy isn't that robust anymore, and I've not read the paper yet, so I don't really know. Histone methylation is a real thing and a cause of some epigenic phenomena, so I'd think something like this is the culprit.
Still, this is a really surprising result, and (sorry to sound like a broken record) more research in needed.
Is "memory" a parameter to a variable mechanism? Does a hardcoded/fixed mechanism express "memory" of its design changes, or does it have no "memory" because of its non-parameterized operational characteristics?
As humans, we sort of consider memories to be data parameters to our flexible thinking processes.
>> .. more like RNA stores/caches the response mechanism of a pain receptor.
The point? We all evolved from very tiny/primitive creatures. It's reasonable to speculate that all of our memories are stored in a similar manner. At some root level all of our consciousness may be conditioned responses by individual cells. All our other complex systems evolved from relatively simpler mechanisms.
I can't be bothered to actually read the actual paper, but I assume that snails that have been stabbed and injected with something similarly irritating are absolutely chill with that and won't withdraw any sensitive bodyparts none whatsoever.
I wonder if it's misleading to use the term "brain" here. It's certainly interesting that RNA can modulate the synaptic activity involved in the gill siphon withdrawal reflex, but the system is pretty far from a brain.
RNA is too short-lived (in the order of minutes to hours) to serve as a long-term memory. Muscle memory, despite the name, corresponds to changes in the brain structure. In a way muscle memory is the exact opposite: it’s a slowly learned, but long-lasting response. Whereas RNA memory, to the extent that it exists, is an immediate but short-lived memory.
> Ryan knows Glanzman and trusts his work. He said he believes the data in the new paper. But he doesn’t think the behavior of the snails, or the cells, proves that RNA is transferring memories. He said he doesn’t understand how RNA, which works on a time scale of minutes to hours, could be causing memory recall that is almost instantaneous, or how RNA could connect numerous parts of the brain, like the auditory and visual systems, that are involved in more complex memories.
It sounds less like the standard definition of "memory", and more like RNA stores/caches the response mechanism of a pain receptor. Thoughts on that interpretation (I'm a layman on these subjects)?