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There are a couple traps to be aware of with this article. 1. "Bioelectricity" This is a generic term which doesn't capture the nuance of charge gradients and

There are a couple traps to be aware of with this article. 1. "Bioelectricity" This is a generic term which doesn't capture the nuance of charge gradients and chemical gradients in cells. While you can directly apply charges to interact with gradient based biological systems, this is a brute force method. Cells have chemically selective walls. So while applying an external electrical voltage can act in a similar manner as causing a neuron to fire, it is far less precise than the calcium and sodium channel mediated depolarization which implements normal firing. Said another way 'bioelectricity' is not simple. 2. Replacement This one is a bit more subtle. If you find that you can affect a system by one means that is not the same thing as saying the means is the cause. Take the example of using RNA to transfer memory from one Aplysia to another. Immediately after transfer the recipient does not have the memory. It takes time for the introduced RNA to affect sensory cells so that they become more sensitive to stimulation. This is in contrast to a trained animal that has already undergone synaptic remodeling. If you have the appropriate synapses but were somehow able to remove all the relevant RNA in an instant, the animal would continue to 'remember' its training. Synapses are sufficient. In reality there are multiple systems that work together over multiple timescales to produce the behaviors we observe. Some of those systems can have their contributions mimicked by other interventions. Because of this complexity you can never say 'it's really about X', the best you can say is 'X plays a major role' or 'X contributes Y percent to this observed phenomenon'.

RaftPeople 3y ago
> This is in contrast to a trained animal that has already undergone synaptic remodeling. If you have the appropriate synapses but were somehow able to remove all the relevant RNA in an instant, the animal would continue to 'remember' its training. Synapses are sufficient. Not if you removed the DNA. Epigenetic changes to the DNA are what maintain the synapse at it's "learned" state. Here's a link: https://www.sciencedirect.com/science/article/pii/S2405844022035800 https://www.sciencedirect.com/science/article/pii/S240584402... In addition, research has shown neurons communicating via mRNA (surrounded by a lipid). https://www.nature.com/articles/d41586-018-00492-w https://www.nature.com/articles/d41586-018-00492-w https://www.inverse.com/article/40113-arc-protein-ancient-mouse-brain-rna-capsid https://www.inverse.com/article/40113-arc-protein-ancient-mo... Lots of interesting stuff in this arena.
- RaftPeople 3y ago
  Additional note: I forgot that synapses are also maintained by local RNA (local=at/near the synapse), so removing the RNA would definitely cause the synapse to revert back to a different state and not retained it's "learned" state.
generalizations 3y ago
> In reality there are multiple systems that work together over multiple timescales to produce the behaviors we observe. Some of those systems can have their contributions mimicked by other interventions. Because of this complexity you can never say 'it's really about X', the best you can say is 'X plays a major role' or 'X contributes Y percent to this observed phenomenon'. You can say the same thing about computer systems - as long as you don't understand the underlying logic. If you don't understand that the chemistry of transistors doesn't matter as much as the C code, you can say exactly the same critique about how a thinkpad works: "So while applying an external electrical voltage can act in a similar manner as causing a neuron to fire, it is far less precise than the calcium and sodium channel mediated depolarization which implements normal firing. Said another way 'bioelectricity' is not simple....In reality there are multiple systems that work together over multiple timescales to produce the behaviors we observe. Some of those systems can have their contributions mimicked by other interventions." Once you do understand the logic - the 'why' of von neumann machines and Javascript and transistors, it's clear that your claim isn't true and there is an underlying logic. The trouble is, until we positively identify that logic, we can't know if it exists or not and we're stuck debating the bioequivalent of the fundamental computational significance of the clock cycle speed of a CPU.
- andsoitis 3y ago
  > there is an underlying logic. The trouble is, until we positively identify that logic, we can't know if it exists or not First you exclaim there is an underlying logic, then in the next sentence you say we don’t know whether it exists, which completely contradicts your claim.
- AlienRobot 3y ago
  I have a very rudimentary understanding of how electricity and electronic circuitry and transistor work, but it does make me wonder: We use programming languages like C to create complex branching algorithms that are turned a linear machine code tape. Programmers generally can not understand assembly even if they understand the branching code that is turned into assembly. Even if assembly had variables, just the fact that if/else's and function calls are turned into jumps is enough to make the code too complicated to understand. It might be possible to disassemble back to C by resolving the jumps into something that is easier to understand. Imagine if brains worked the same way. That there is actually a naturally-forming high level "brain language" that is turned by a "brain compiler" function into a low-level "brain assembly," but when we look at it all we see is the assembly. That what the brain is actually doing is relatively simple, but because we can only observe the output of the compiler function it appears to be insanely complex to reverse-engineer. Then again, I don't have the faintest idea of how brains work either.
daveguy 3y ago
> Said another way 'bioelectricity' is not simple. > If you have the appropriate synapses but were somehow able to remove all the relevant RNA in an instant, the animal would continue to 'remember' its training. Synapses are sufficient. I'm not sure these two statements are compatible. The first is definitely true, and rna does function on a slower timescale. We can't be 100% confident that some of the complexity we don't understand in the first statement wouldn't have an impact in the second scenario, can we?
eurekin 3y ago
Where one can learn about that in more details?
nickpsecurity 3y ago
I also want to know how much of this was replicated by independent, skeptical sources looking for alternative explanations. One thing I see in “science” reporting is that one or a few people make wild claims, it hits the news, and people believe their word on faith with no replication. There’s also many statements about what we know where the claims made should have citations, too. Yet, people who have never run experiments like that are nodding along saying, “Of course it’s true.” Or was all this replicated? What strengths and weaknesses did they hypothesize in these studies? What did they prove or disprove? What’s the next steps? And can we already implement any of those in simulators? (Note: I think agents poking and prodding the world can definitely be implemented in simulators. Even primitive, game engines should be able to model some of that.)
dekhn 3y ago
I am not sure I would call RNA transferring regulatory programs "memory". This looks more like epigenetic transfer than what we would call memory (IE, factual recall). My training was before the more recent work with Aplysia, but "RNA memory transfer in planaria" was presented as an example of "how to make big claims with irreproducible experiments" in grad school. I appreciate that epigenetics is a well-established field at this point but I worry people conflate its effects with other phenomena.
- RaftPeople 3y ago
  I tend to agree that the word "memory" makes me think of a higher level (more abstract) type of action than a simple reactive switch, I'm not sure where the line is or if there really needs to be one or not. Having said that, are you familiar with the purkinje cell from a rabbit that they trained to respond to timed patterns of input in isolation? Timed pattern=input 1, delay X, input 2, delay Y, then input 3. Definitely more than a simple on/off switch type training, but does that rise to the level of "memory"?

RaftPeople 3y ago

> This is in contrast to a trained animal that has already undergone synaptic remodeling. If you have the appropriate synapses but were somehow able to remove all the relevant RNA in an instant, the animal would continue to 'remember' its training. Synapses are sufficient. Not if you removed the DNA. Epigenetic changes to the DNA are what maintain the synapse at it's "learned" state. Here's a link: https://www.sciencedirect.com/science/article/pii/S2405844022035800 https://www.sciencedirect.com/science/article/pii/S240584402... In addition, research has shown neurons communicating via mRNA (surrounded by a lipid). https://www.nature.com/articles/d41586-018-00492-w https://www.nature.com/articles/d41586-018-00492-w https://www.inverse.com/article/40113-arc-protein-ancient-mouse-brain-rna-capsid https://www.inverse.com/article/40113-arc-protein-ancient-mo... Lots of interesting stuff in this arena.

RaftPeople 3y ago
Additional note: I forgot that synapses are also maintained by local RNA (local=at/near the synapse), so removing the RNA would definitely cause the synapse to revert back to a different state and not retained it's "learned" state.

generalizations 3y ago

> In reality there are multiple systems that work together over multiple timescales to produce the behaviors we observe. Some of those systems can have their contributions mimicked by other interventions. Because of this complexity you can never say 'it's really about X', the best you can say is 'X plays a major role' or 'X contributes Y percent to this observed phenomenon'. You can say the same thing about computer systems - as long as you don't understand the underlying logic. If you don't understand that the chemistry of transistors doesn't matter as much as the C code, you can say exactly the same critique about how a thinkpad works: "So while applying an external electrical voltage can act in a similar manner as causing a neuron to fire, it is far less precise than the calcium and sodium channel mediated depolarization which implements normal firing. Said another way 'bioelectricity' is not simple....In reality there are multiple systems that work together over multiple timescales to produce the behaviors we observe. Some of those systems can have their contributions mimicked by other interventions." Once you do understand the logic - the 'why' of von neumann machines and Javascript and transistors, it's clear that your claim isn't true and there is an underlying logic. The trouble is, until we positively identify that logic, we can't know if it exists or not and we're stuck debating the bioequivalent of the fundamental computational significance of the clock cycle speed of a CPU.

andsoitis 3y ago
> there is an underlying logic. The trouble is, until we positively identify that logic, we can't know if it exists or not First you exclaim there is an underlying logic, then in the next sentence you say we don’t know whether it exists, which completely contradicts your claim.
AlienRobot 3y ago
I have a very rudimentary understanding of how electricity and electronic circuitry and transistor work, but it does make me wonder: We use programming languages like C to create complex branching algorithms that are turned a linear machine code tape. Programmers generally can not understand assembly even if they understand the branching code that is turned into assembly. Even if assembly had variables, just the fact that if/else's and function calls are turned into jumps is enough to make the code too complicated to understand. It might be possible to disassemble back to C by resolving the jumps into something that is easier to understand. Imagine if brains worked the same way. That there is actually a naturally-forming high level "brain language" that is turned by a "brain compiler" function into a low-level "brain assembly," but when we look at it all we see is the assembly. That what the brain is actually doing is relatively simple, but because we can only observe the output of the compiler function it appears to be insanely complex to reverse-engineer. Then again, I don't have the faintest idea of how brains work either.

daveguy 3y ago

> Said another way 'bioelectricity' is not simple. > If you have the appropriate synapses but were somehow able to remove all the relevant RNA in an instant, the animal would continue to 'remember' its training. Synapses are sufficient. I'm not sure these two statements are compatible. The first is definitely true, and rna does function on a slower timescale. We can't be 100% confident that some of the complexity we don't understand in the first statement wouldn't have an impact in the second scenario, can we?

eurekin 3y ago

Where one can learn about that in more details?

nickpsecurity 3y ago

I also want to know how much of this was replicated by independent, skeptical sources looking for alternative explanations. One thing I see in “science” reporting is that one or a few people make wild claims, it hits the news, and people believe their word on faith with no replication. There’s also many statements about what we know where the claims made should have citations, too. Yet, people who have never run experiments like that are nodding along saying, “Of course it’s true.” Or was all this replicated? What strengths and weaknesses did they hypothesize in these studies? What did they prove or disprove? What’s the next steps? And can we already implement any of those in simulators? (Note: I think agents poking and prodding the world can definitely be implemented in simulators. Even primitive, game engines should be able to model some of that.)

dekhn 3y ago

I am not sure I would call RNA transferring regulatory programs "memory". This looks more like epigenetic transfer than what we would call memory (IE, factual recall). My training was before the more recent work with Aplysia, but "RNA memory transfer in planaria" was presented as an example of "how to make big claims with irreproducible experiments" in grad school. I appreciate that epigenetics is a well-established field at this point but I worry people conflate its effects with other phenomena.

RaftPeople 3y ago
I tend to agree that the word "memory" makes me think of a higher level (more abstract) type of action than a simple reactive switch, I'm not sure where the line is or if there really needs to be one or not. Having said that, are you familiar with the purkinje cell from a rabbit that they trained to respond to timed patterns of input in isolation? Timed pattern=input 1, delay X, input 2, delay Y, then input 3. Definitely more than a simple on/off switch type training, but does that rise to the level of "memory"?