12 ms·
Memory transfer between snails challenges view of how brain remembers
- intrasight 9y agoMy guess is that their RNA solution also contained neurotransmitters
- klmr 9y agoEven if: neurotransmitters are extremely short-lived, and almost completely unspecific: they’re either generally excitatory or inhibitory, they don’t encode complex messages. They experimental setup sufficiently controls for that due to the duration of the wait between the RNA injection and the stimulus exposure.
- intrasight 9y ago"neurotransmitters are extremely short-lived, and almost completely unspecific" That's the assumption that I think needs to be further validated.
- omtinez 9y agoMaybe someone can take a second look at the paper. I couldn't find the published version, just a manuscript[1] (kudos to the authors for making it available under CC license). But... The only reference I could find about the sample size says: > "To prepare a single RNA injection, the pleural-pedal and abdominal ganglia were removed from 4-5 sensitization-trained animals—or from 4-5 untrained controls—immediately after the 48-h posttest" 4-5??? I really hope that I'm missing something here, otherwise I find truly depressing how low the bar is for scientific journals. [1] http://www.eneuro.org/content/eneuro/early/2018/05/14/ENEURO.0038-18.2018.full.pdf http://www.eneuro.org/content/eneuro/early/2018/05/14/ENEURO...
- rf15 9y agoI'm sorry, Sturgeon's Law is in full effect and the current system encourages spamming out low-tier research for grants/etc.. So the bar is on a completely different metric altogether from what a normal person would expect
- klmr 9y agoFigure legend 1D says: “Control RNA (5.4 ± 3.9 s, n = 7) and Trained RNA (38.0 ± 4.6 s, n = 7)” That’s a relatively low n but it might be sufficient. However, they don’t explain how the number was reduced from ~30 donor animals to 7 test animals. This might be entirely reasonable though (I know nothing about working with Aplysia).
- otp124 9y ago> 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)?
- gwerbret 9y agoMy 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.
- pishpash 9y agoGenetic 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.
- empath75 9y agoIt 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.
- eof 9y ago> RNA stores/caches the response tomato / tomato -- right? what is storage/cache if not memory? 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.
- rejectedalot 9y agoIt says that the snails retracted only briefly as a baseline, but learned to retract for longer periods of time to avoid the jarring electrical stimuli. I’m totally unfamiliar with this stuff, but it seems to me that injecting a snail with RNA would also be a jarring stimulus. Therefore, wouldn’t it be learning from the injection itself to remain in its shell for longer at a sign of human touch?
- eastophe 9y agoThey injected the other snails with control RNA from snails which were not subject to the shocks. In other words, they did control for this.
- mattnewton 9y agoCame back here to say this. The relevant part: “Control snails that received injections of RNA from snails that had not received shocks did not withdraw their siphons for as long.”
- rejectedalot 9y agoI missed that - thank you for clearing this up!
- roywiggins 9y agoI for one welcome our new hive mind snail overlords.
- sandov 9y agoApparently fun is not allowed in HN, judging by the gray text.
- javascript-this 9y agolol...thanks for this
- dotancohen 9y agoSo sad to know that this will be downvoted to oblivion. I would like to subscribe...
- pbhjpbhj 9y agoBut /. still flourishes on hot-grits and such, so don't be sad, just go there. Not all communities need [devolve] to be the same.
- williamxd3 9y agoSo synapses are like a fast cache for memory stored in neurons nucleus?
- mattnewton 9y agoMaybe. Maybe there was a problem or it will fail to replicate.
- daemonk 9y agoI think this was proposed back in the 60s with flatworms. There are some recent experiments, again with flatworms, where they studied this. Flatworms can regenerate heads. So they trained a flatworm to avoid a certain type of light and cut the head off and allowed the tail to regenerate back a new head. I think they claimed that the newly regenerated animal exhibit the same behavior.
- otoburb 9y ago>>I think they claimed that the newly regenerated animal exhibit the same behavior. As directly referenced in the article, flatworm experimenters (James McConnell in the 50's and 60's, and Michael Levin in 2015[1]) definitely claimed regenerated flatworms exhibited the same behaviour. [1] https://www.theverge.com/2015/3/18/8225321/memory-research-flatworm-cannibalism-james-mcconnell-michael-levin https://www.theverge.com/2015/3/18/8225321/memory-research-f...
- fhayde 9y agoMaybe there's a transitive relationship between the environment before and during transcription and the resulting RNA that in turn can affect its environment. It would be difficult to identify in vivo because the environment is already synchronized with the changes that may have been introduced from the RNA, but in vitro maybe the effects of the altered RNA would become apparent in an unmodified environment. Vice versa, if you could measure enough samples of RNA from the same organism and source DNA I wonder if there'd be a quantifiable difference when the environment was subject to the same sort of changes that occur when memories are formed and an unmodified environment. Really cool research!
- beached_whale 9y agoI wonder how this relates to Slime Molds. There was a Science Friday segment on them and, if I remember correctly, they showed memory and memory transfer too.
- ChuckMcM 9y agoI suppose we could call this effect "snail mail" :-) More seriously though, while I understand the basic method they used for their experiment, where is the theory about how the brain can catalyze the RNA into understanding in millisecond times rather than days. Or is it perhaps an epigenetic marker that signals "danger" ala the learned muscle memory 'flex' from negative stimulus?
- AgentME 9y ago>where is the theory about how the brain can catalyze the RNA into understanding in millisecond times rather than days. Maybe the brain often serializes memories from neurons into RNA and vice versa often in order to replicate the memories throughout the brain. The RNA injection caused some memories to be deserialized into the snail's neurons, and the memory now in the neurons is what is affecting the snail's reaction.
- reilly3000 9y agoI wonder if environmentally ambient RNA could impact gene expression in humans. RNA directly impacts gene expression: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2612776/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2612776/ Say we swap some bacteria by using the same public restroom paper towel dispenser. Your bacteria happens to carry some tragic memory of stress encoded into some miRNA that formed when traveling to somewhere with very cold temperatures. Certainly gene expression wouldn't be affected by a small bacteria colony, but maybe if there was repeated exposure, every day in the same place or with the same people, would I think twice about visiting Alaska? I have observed how places like cities tend to affect people's 'look' in semi-coordinated ways. How spending sustained time with a group of friends really does change a person in subtle ways. Is there any way that ambient miRNA could be a part of that process? Is there a way we can be sure that it isn't a factor?
- tim333 9y agoIt's going to be hard for enough RNA to do anything to get in to your nervous system from the towel dispenser. I'd put peoples looks changing that way down to peer pressure and the like.
- z3t4 9y agoIt would be interesting to see a "diff" on the injection samples. With brute forcing we could figure out how to program these sequences. Biological robot snails!
- klmr 9y agoThat’s probably the next step (the authors raise the question of the identity of the implicated RNA). Transcriptome profiling (which this is) has become extremely routine recently. In fact, it’s highly unorthodox that this analysis isn’t already part of the original paper (to clarify: it’s completely fine, but quite unusual, to leave it as a follow-up study).
- etatoby 9y agoThe larger hyphothesis, if I understand correctly, is that RNA (and possibly DNA?) is the seat of long-term memory and has some hereditary or otherwise physically transferable component, while synapses would be our short-term memory, as well as the expression or "cache" of the former. This, as well as the worm-eating-worm-acquires-its-memory research, if true (a big if) would vindicate so many theories, findings, and "magic" traditions from around the world. From Carl Jung's Collective Unconscious: https://en.wikipedia.org/wiki/Collective_unconscious https://en.wikipedia.org/wiki/Collective_unconscious to many old cultural traditions of eating certain animal/human parts in order to acquire their psychological properties such as courage. I, for one, am looking forward to my injections of foreign languages and musical instrument playing.
- ralusek 9y agoI know Kung Fu.
- deleted 9y ago[deleted]
- csomar 9y ago> This, as well as the worm-eating-worm-acquires-its-memory research, if true (a big if) would vindicate so many theories, findings, and "magic" traditions from around the world. We don't have the same digestive metabolism as worms. I don't think the RNA is going to make it from your stomach to your brain.
- beobab 9y agoI don't think so either, but that's not science. I haven't checked, and apparently neither has anyone else. yet Further study is required. Facts must be established.
- csomar 9y agoI mean if the RNA is going to dissolve in the stomach acid. Then there is no way it is going to make it to the brain? And does the RNA transfer through blood on its own? That's science. The only possible explanation is that they picked up something else along RNA that does affect memory and they are not aware of it.
- jonmc12 9y agoI was surprised to find so many studies regarding the relationship between long-term memory, an enzyme (PARP-1, usually associated with DNA repair and inflammation), and RNA. Seems relevant to Glanzman's research, but not cited. In 2004 the enzyme PARP-1 was linked to long-term memory in Aplysia[1]. In 2009 another study claimed that PARP-1 was also required long-term memory in Mammals[2]: "Previous results linked the activation of PARP‐1 with long‐term memory formation during learning in the marine mollusk Aplysia (Science 2004, 304:1820–1822).. Mice were tested in two learning paradigms, object recognition and fear conditioning.. These findings implicate PARP‐1 activation in molecular processes underlying long‐term memory formation during learning." Another study of mice "demonstrated that augmentation of the stability of pro-inflammatory mediator mRNAs presenting a regulatory mechanism of PARP1 in gene expression at the post-transcriptional level".[3] [1] http://science.sciencemag.org/content/304/5678/1820 http://science.sciencemag.org/content/304/5678/1820 [2] https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1471-4159.2009.06296.x https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1471-4159.... [3] https://www.nature.com/articles/ncomms14632 https://www.nature.com/articles/ncomms14632
- loa-in-backup 9y agoTransfer of fluid in fluid based capacitors at different level of charche would basically also exchange circuit response times (in specific cases) so I'm not too keen on making ut memory transfer. What if they transfered a snail equivalent of cortisol ("stress hormone").
- John_KZ 9y agoThis was my first though too. Something happened, but it was not memory transfer. However RNA and biological indicators like hormones could (and probably do) have a big effect on learning, in terms of how fast we learn, how aware to be, feedback mechanisms, triggering long-term memory formation etc. The idea of storing memories in genetic materia has been really popular for a long time, but imo this is mostly due to either hope/belief for immortality and romantic trans-generational memory transfer, or new age trends. Of course it's not impossible, but it's very unlikely.
- deleted 9y ago[deleted]
- blixt 9y agoWould this be similar to past studies[1][2] in how stimuli responses (e.g., fear to smell) can be inherited between generations? The question is if we can ever transfer complex structured memories (knowledge, past experiences) or if these transferable memories are limited to basic emotional responses to specific signals? I thought more complex memories were spread across many cells in the brain, in a seemingly random structure when compared to another brain, making transfer between brains incompatible. [1] Worms: https://www.cell.com/cell/fulltext/S0092-8674(16)30207-0 https://www.cell.com/cell/fulltext/S0092-8674(16)30207-0 [2] Mice: https://www.nature.com/articles/nn.3594.epdf?referrer_access_token=13Y364MbUlYxwFlwbk8OuNRgN0jAjWel9jnR3ZoTv0MLhU4y4LZkONbbyIJwg8aPE0a1CCLmPmXJKFoyJaXxxaLY7RGhRQ9FdNDfwJ4apxIigJuQ54uRTkEl2Q2P0XKxvMb54h0QK8VvqSlDqBdgJPNXAyiH0jwIDJmBbsDXHWgHUVeWTevx9KEAco7GZSPrAdsfyhHXLGtF0JCacqmyIE8pcR9shg0hKG_RRrq6PMC9IY6yGVHeqMwq9_RvONKg&tracking_referrer=www.scientificamerican.com https://www.nature.com/articles/nn.3594.epdf?referrer_access...
- csomar 9y agoI think, on the positive side, it'll make people reconsider that genetics and race affect intelligence (and maybe gender?). We are too stubborn and politically correct to discuss it. I kinda think it is true because my dog (a german shepherd) is definitively a lot smarter and dexterous than the other "normal" dogs. Hopefully, we'll be able to inject the intelligence DNA and everyone can get a fair share of intelligence. > 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. I was puzzled by that too. Also, it is not like they go pick a fork and select the RNA. I wonder if they "picked up" something else along the way?
- crummy 9y agoIsn't it likely that training has a significant effect on the apparent "intelligence" of different dogs?
- csomar 9y agoNo. The german shepherd picks up very fast comparing to other dogs. It also has dexterity. My dog figured out how to open various door by just watching us come and go. The opening mechanism required some dexterity and manipulation. No other dogs did that before.
- klmr 9y ago> it'll make people reconsider that genetics Yes, > and race affect intelligence no. To clarify: it’s extremely well established that genetics strongly affects intelligence [1]. Nobody in the field is denying (or ignoring) this. It’s just hard to exploit at the moment. But “race” is a different matter, and other people have written eloquently (e.g. [2]) about it so I won’t rehash the argument. As a tl;dr: the social construct we call “race” has no relationship with genetic variability in humans. If somebody tells you otherwise, they don’t understand genetics. To put it simply, the labels “Black”, “Caucasian” or “Asian” don’t corresponds to our evolutionary heritage. Actual races (if we were to define them) would look something like “Bantu”, “Yoruba”, 10 more African races, and “pretty much all the rest” (see e.g. [3]). Contrary to the frequent suggestion that science ignores race due to “political correctness”, this simply isn’t true (have you met scientists? they’re not generally known for being politically correct). Science is aware of race, but it’s an unhelpful concept for modern research. [1] https://en.wikipedia.org/wiki/Heritability_of_IQ https://en.wikipedia.org/wiki/Heritability_of_IQ [2] https://www.salon.com/2017/10/18/how-genetics-undermines-scientific-arguments-for-racism/ https://www.salon.com/2017/10/18/how-genetics-undermines-sci... [3] http://www.pnas.org/content/107/2/786 http://www.pnas.org/content/107/2/786
- ThoAppelsin 9y agoFinally a childhood dream of the many can be established through this alleged innovation: Learning math, physics, etc. through simple injection, information pills, etc.
- baalimago 9y agoNot sure how good this would be, deviations in learning creates further developments in the fields. A child prodigy's idea of some odd physics occurrence might one day grow into some completely new field of science. I suppose I'm a memory conservative, I think I'll prefer the good old way, no matter how cool that scene from the Matrix is
- baalimago 9y ago“It’s pretty shocking,” said Dr. Todd Sacktor, and giggled internally
- barrkel 9y agoLet's not forget that it's also perfectly possible to have multiple mechanisms for remembering things; there seems to be a false dichotomy being presented here, either RNA or synaptic strength or synaptic topology. There are different modes of memory too: the way you remember something as muscle memory, vs short term memory, vs associative memory, etc.
- slfnflctd 9y agoThe possibility that different types of memories are stored in varying places or ways based on unknown criteria is highly intriguing. If there is more than one way to store/trigger a memory, that means a larger 'attack surface', and therefore the process should be easier to hack.
- transfire 9y agoInterestingly, L. Ron Hubbard put forth the notion of cellular memory a long time ago -- it is part of the premise of Dianetics. I think Gene Roddenberry may have believed this too. I recall an early Star Trek NG episode where Data told Geordi that's how human memory works, contrasting it to how his positronic brain worked.
- dschuetz 9y ago> “It’s as if we transferred a memory,” Glanzman said. No, sorry. They did not transfer "memory", they transferred some specific RNA which modulates some specific neuron activity. "Memory transfer" is a gross misinterpretation of what they actually did there. Ugh.
- jghjg 9y agoofftopic but, I find this "magazines" that use to appear on HN interesting Which ones do you guys recommend and what's the best way to be subscribed to them?
- helpfulanon 9y agoI know this will be an unpopular comment, but I've had a long-held theory that past lives / reincarnation is a real phenomenon with a biological mechanism that is as-yet unknown. The theory being that trauma at time of death is somehow encrypted for the next generation and passed on shortly after death, particularly if a corpse enters the water or food supply. The basis for this is a little embarrassing.. I had memories of being a bridge engineer, frequent dreams of falling off a very specific truss bridge in my head in childhood. To this day I'm terrified of certain types of truss bridges, which are coincidentally quite common upriver of where my parents lived when I was born, and where our water came from. This theory would also explain why river burial is commonly associated with reincarnation. Committing the tissue of a deceased person into a community water supply would increase transfer of memory.
- meowface 9y agoIt doesn't seem physically impossible, but this would mean "past lives" can only be from your direct ancestors. But regardless, there's no evidence to support it and even this snail experiment is a far cry from proving memories can even be transferred to humans, let alone inherited.
- nickpsecurity 9y agoA lot of creatures reduce contact with something that just caused them a lot of pain. I'd have asked if they ruled out whether the snails also withdraw a bit after someone stabbed them with a needle. The subsequent test on Petri dishes lends more credence to the theory, though, that the reaction is stored and moving.
- vivekd 9y agolayperson's question: Since rna is gets information from the dna and is involved in the expression and regulating of genes, does this mean that memory somehow becomes encoded in our genes?
- magicalhippo 9y agoThe RNA can turn off and on production of proteins no? If so, then surely the ratio of proteins can affect the touch response sensitivity? After all, it's not like he transferred memory of a complex maze.
- tneely 9y ago> It is generally accepted that long-term memory (LTM) is encoded as alterations in synaptic strength. > RNA from a trained animal might be capable of producing learning-like behavioral change in an untrained animal. Why did the author jump to the conclusion that RNA == LTM, when that RNA is most likely just the driver for modulating synaptic strength? Whatever RNA they extracted could easily just encode for various synaptic proteins.
- vivekd 9y agoBut wouldn't that still inevitability lead to the conclusion that rna is where memories are stored and synaptic strength is just how memory gets expressed in a way our brains can interact with.