[HN Gopher] RNA Memory Hypothesis
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RNA Memory Hypothesis
Author : nahuel0x
Score : 56 points
Date : 2021-02-03 13:00 UTC (10 hours ago)
(HTM) web link (scottlocklin.wordpress.com)
(TXT) w3m dump (scottlocklin.wordpress.com)
| tokipin wrote:
| One of my theories is that this (or similar virus-like mechanism)
| is how some memories are transferred to offspring. The reasons
| are:
|
| * Prodigies which happen to be good in a field related to what
| their parents are good at. Often the wording used indicates a
| memory-like reason. For example, finding the rules of chess
| "familiar."
|
| * Embeddings in machine learning, which allow encoding of high-
| dimensional information in a low-dimensional space. This would
| imply that humans have a somewhat-shared embedding space at some
| "layers". It's interesting to wonder how similar this space would
| be across various animals, as it would effectively be an evolved
| language.
|
| * Other more subtle things, like the "cultural memory" of a
| society.
|
| One question would be what types of time scales these memories
| survive across. Maybe some forms of instinct are deep memories
| that have been directly encoded in DNA.
| subroutine wrote:
| This is nonsense. Evidence collected over the last 40 years have
| detailed how memory is encoded by synaptic weights, but the
| premise...
|
| "there's no obvious way for all that sensory data to be captured
| in synapses as long term memories"
|
| ...just ignores these findings. The model described in the
| article on the other hand, has never been observed. At the least,
| if you are going to propose an mRNA hypothesis don't use "T" as
| one of your RNA bases.
| titzer wrote:
| > have detailed how memory is encoded by synaptic weights
|
| Synaptic weights is our computational model of neural networks
| that seems to work pretty well. But this is a model. No one has
| discovered the biological mechanism by which synapses are
| "weighted". The actual computation going on in a cell is
| totally based on chemistry.
|
| There are a lot of different specialized networks in human and
| animal brains that don't necessarily translate easily to
| "weighted synaptic networks" all that well. For example,
| networks that process audio information have been shown to
| recognize individual frequencies (in fact, they pretty much
| solely do this!) Such networks seem to be primarily based on
| the firing rate across a synapse. For such networks is seems
| more reasonable to think of neurons as signal processors whose
| internal computation is more based on the time domain, e.g.
| some kind of Fourier transform-equivalent.
|
| In short, I think you should put less weight (pun intended) in
| our computational model of neurons (link weights) and look more
| at biology.
| jrussino wrote:
| It has been over a decade since I studied neurobiology, but
| from what I recall we do have at least some understanding of
| how synapses become "weighted". For example: long-term-
| potentiation, the idea that "neurons that fire together wire
| together" https://en.wikipedia.org/wiki/Long-
| term_potentiation https://www.khanacademy.org/test-
| prep/mcat/behavior/learning...
| netizen-9748 wrote:
| LTP is only one mechanism. Neurons vary their responses in
| multiple ways, usually some form of receptor protein
| modification. But again, this is one mechanism of many.
| AstralStorm wrote:
| What is the physical realisation of the synaptic weight?
| (Here's trouble, we do not know. It's not in just connectivity
| or myelination.)
| jrussino wrote:
| See my response to your sibling comment; clearly we still
| have a lot to learn, but there is already _some_
| understanding of the biological mechanisms of synaptic
| plasticity (which I think is what the parent comment is
| referring to as "synaptic weights").
|
| https://en.wikipedia.org/wiki/Synaptic_plasticity
| nynx wrote:
| Very interesting, but also worrying, in a way. If neurons are
| actually reasonably large, complex computers in their own right,
| brain emulation is much further off than some people are
| thinking. It's possible that ASC brain preservation doesn't
| preserve the internal details necessary if this hypothesis ends
| up being true.
| [deleted]
| asdfasgasdgasdg wrote:
| To be fair it's more than just possible that ASC brain
| preservation doesn't work even under any other hypothesis of
| cognition.
| nynx wrote:
| That's true. I think the fair way to put it that it's
| possible that ASC preserves the necessary data to simulate a
| brain.
| [deleted]
| blackrock wrote:
| What I find fascinating, is that babies are born knowing how to
| suck.
|
| How? It's not something you can teach them. They say its an
| innate thing. But what does that even mean.
|
| I think babies are born with this programmed into them. Like a
| genetic type of memory.
|
| Then over time, the neurons establish more connections, and learn
| more advanced things. But the spark for that was set off at
| birth.
| woeirua wrote:
| I agree that there must be some genetic component to it, but if
| that were the case then by the law of large numbers we should
| have seen some counter examples by now too, i.e. babies that
| lack the instinct to suck or cry, etc. It'd be interesting to
| know if they show any obvious genetic changes that could
| explain that behavior. Casual googling hasn't turned up
| anything, but I'm sure someone has looked into it somewhere...
| fabian2k wrote:
| I don't think there's any real doubt that memory is stored in
| neurons, this is really a fringe theory. I haven't looked at it
| closely, but my first objection would be that RNA would be far
| too slow for this purpose. It's also not stable over time, cells
| have mechanisms to intentionally degrade it. It just doesn't make
| sense.
|
| There are other weird parts in the blog post, for example
| claiming that a particular protein kinase is involved in mRNA
| transcription. That is by definition wrong as a kinase is an
| enzyme that transfers a phosphate, so a protein kinase transfers
| phosphates to proteins. And the RNA in this hypothetical memory
| storage would not be mRNA, as that by definition encodes for
| proteins.
|
| The person cited in the post is also a crackpot, I've quite a lot
| of experience with his exploits on the Stack Exchange network.
| And I haven't found a conspiracy theory yet that he didn't like.
| This is not hyperbole, I learned of a whole bunch of conspiracy
| theories I didn't know existed through his posts.
| macawfish wrote:
| RNA is literally a form of memory. The question should not be
| whether or not memory is encoded in RNA, it should be "what are
| all the ways that creatures with RNA can experience the
| encoding and decoding of information encoded in RNA?"
|
| Memory is literally everywhere. There is already evidence that
| the brain can encode memory in dynamic molecular processes, and
| that interference of those process can interfere with an
| animal's ability to recall memory.
|
| Your point about timescales is a good one, and provides a clue:
| the timescales over which a given medium of information can be
| encoded to or decoded from and over which it decays should
| provide a clue about the timescales we might expect organisms
| to experience it in. Mammals and other creatures with RNA
| experience memory over a whole continuous range of timescales.
| Why wouldn't RNA, which is optimized for encoding information,
| be just one of many mediators of memory?
| fabian2k wrote:
| Most of the RNA in our cells simply encodes for proteins. The
| information is entirely redundant as it is simply copied from
| DNA. I would not call that memory.
|
| Of course there's a lot of other stuff RNA can do like
| catalytic activity, triggering RNA interference or reacting
| to other molecules (riboswitches). But information storage
| isn't really anything RNA is known for.
| Communitivity wrote:
| The article points out that while far from being widely
| accepted, this theory is getting a new look because of some
| experimental evidence that supports it.
|
| > I don't think there's any real doubt that memory is
|
| > stored in neurons, this is really a fringe theory.
|
| All theories are fringe theories at first, that's where they
| start (as hypothesis before there's any experimental evidence
| or mathematical proofs).
|
| I would agree that there is little doubt that memory is stored
| in neurons. However, that does not exclude some memory being
| stored elsewhere. It's generally accepted that the brain stores
| memories first in short term memory, and then after a time some
| of those memories are stored in long term memory, with the
| memories chosen according to some criteria.
|
| I could see RNA memory as a third stage of memory storage.
| Memories that the brain views as high impact to the species
| according to some criteria might get copied from long term
| memory into RNA memory to be passed on to future generations,
| accessible only by subconscious.
| fabian2k wrote:
| That link to the experimental evidence is just an article.
| And that article mentions experiments by David Glanzman, but
| I can't find any publications by him on Pubmed in the
| mentioned timeframe. I don't see any new experimental
| evidence here.
| wombatmobile wrote:
| > The person cited in the post is also a crackpot
|
| My first reaction was to downvote your comment for the ad
| hominem, which doesn't contribute to the discussion. But I can
| see you are giving consideration to the article, and want to
| discuss it further - it's just that you haven't got enough out
| of it to make much of a start, and so this is your conversation
| starter.
|
| I'm assuming you've labelled this a "fringe theory" by a
| "crackpot" not to be nasty, buy in order to start a
| conversation.
|
| Let's start with your statement:
|
| > I don't think there's any real doubt that memory is stored in
| neurons
|
| The question is "how?". The article is postulating that each
| neuron is a computer, and RNA is a storage medium.
|
| You say "my first objection would be that RNA would be far too
| slow for this purpose." That's because your thinking about RNA
| is limited to what you understand about RNA. You've learned
| about mRNA, which is one application that uses this molecular
| format, but it's not the only possible application.
|
| The article suggests that the data transmission protocol which
| leads to thought and/or behaviour could be electrical, through
| simultaneous aggregated neuronal RNA based data processing.
|
| Read the section he quotes from Ron Maimon, subtitled RNA
| ticker tape. What do you make of this statement?
|
| "The RNA in a cell is the only entity which is active and
| carries significant bit density."
| fabian2k wrote:
| There are a lot of claims without any evidence in that blog
| post. "The RNA in a cell is the only entity which is active
| and carries significant bit density." is one of them.
|
| DNA certainly encodes for a significant amount of information
| as well. And why not proteins, there are a lot of proteins in
| a cell and you can also modify them in various ways. A cell
| has an enormous amount of state, any of it could
| theoretically store information like memory. There are a lot
| of different molecules active in a cell, in various
| modification states, at various locations, and all of that
| could encode information.
|
| What this blog posts doesn't provide is _any_ experimental
| evidence, this is a pure thought experiment. If RNA were to
| actually store memory, that would be great. Because
| determining the RNA sequences inside a cell is something we
| can do.
| wombatmobile wrote:
| > DNA certainly encodes for a significant amount of
| information as well. And why not proteins
|
| True!
|
| > What this blog posts doesn't provide is any experimental
| evidence, this is a pure thought experiment.
|
| Yeah, so?
| bencollier49 wrote:
| Hard drives couldn't possibly contain operating systems -
| they're much too slow to run them.
| blackrock wrote:
| Are the solid state hard drives of today, faster than the RAM
| memory from the 1990s?
| wombatmobile wrote:
| Good comment, but it might be a little too cryptic.
|
| Another attempt:
|
| Straw man:
|
| Phones are too slow and too dangerous to be used as a real
| time vehicular traffic indicator. If drivers were to text
| their location back to google every 10 seconds, they would
| have too many accidents. It isn't even possible to look up
| the location on google maps and then text a geocoordinate in
| 10 seconds. Drivers just wouldn't do this anyway because
| there is no incentive for them to do so. Google would have to
| pay drivers $2 or so for each location bulletin. That would
| cost billions and google would go bankrupt.
| blackrock wrote:
| > accounts of people "inheriting" memories after organ
| transplants
|
| This is interesting.
|
| So if you transplant a liver, you get memories of the donor's
| eating habits? LOL.
| pippy wrote:
| There's clear evidence of epigenetics playing a role in brain
| activity, though these are more linked to hormonal responses such
| as stress. It's also been proven that RNA transcripts are used to
| trigger maternal instincts when a zygote is present in a mother:
| https://en.wikipedia.org/wiki/Epigenetics
|
| Scientists have already modeled memory retrieval using current
| neural network models. There's literally videos on youtube
| demonstrating this. I'd be surprised if RNA was used to encode
| memories to the extent OP is suggesting: there would have to be a
| mechanism for storing this RNA inside cells or there would be
| evidence of random strands of RNA floating around in the body. We
| would have been found it a long time ago, and scientists would
| also be able to decode it if these strands of RNA were
| standardized and could be transferred person to person.
|
| Though the way evolution works and how complicated the body is,
| it could be occurring in a small sub process in a neurons
| somewhere in the body. though this would likely be tied to
| hormonal responses or something equally boring.
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