11 ms·

Map of an Insect’s Brain

278 points by mkmk 4y ago

nawgz 4y ago
"With 3,016 neurons and 548,000 connections, called synapses, the result is by far the most complex map of a whole brain ever made." "Researchers have also mapped 25,000 neurons and 20 million synapses in the brain of an adult fruit fly, but this is still just a partial [map]" "Human brains have an estimated 86 billion neurons and hundreds of trillions of synapses" The scales at play here are hard to imagine. This is very interesting but it seems the most interesting facet is the completeness, and not just the absolute scale.
GordonS 4y ago
> The connectome of the larval fly, published Friday in the journal Science, took 12 years to complete. Imaging a single neuron required about a day... > Human brains have an estimated 86 billion neurons and hundreds of trillions of synapses... So, the techniques used for the fly are totally impractical for humans, or presumably any mammal. Anyone know of any developments that may help? Maybe AI could be used to automate processing of the images?
- kuprel 4y ago
  “If the human brain were so simple that we could understand it, we would be so simple that we couldn’t.” Maybe AI can though
  - notfed 4y ago
    Asking AI to map human brains...what could possibly go wrong?
- dredog 4y ago
  Yep, this is already happening. I think it’s called ‘automatic segmentation’.
- undersuit 4y ago
  Do we need to image all 86 billion? A sampling of cells throughout the brain and a simulation of a cell such that we can figure out how 1 fertilized egg can become 86 billion neurons and change. We can throw compute power at that, we don't really have brains to throw at the problem.
- inportb 4y ago
  More like totally impractical for living specimens that you want to continue living meaningfully.
- moonbreams 4y ago
  The sell with this kind of research is that doing it will lead to order of magnitude gains in complexity - compare the time it took to sequence the first fruit fly genome with the time it takes today
usgroup 4y ago
i intuitively think that there is something similar in kind between a fruit fly brain and a human brain regardless of the scale, and that cracking the smaller case will somehow lead to cracking the larger one. However, rather than hope, it leads me to a negative conclusion. That is, even at orders of magnitude smaller scales, and with full knowledge of how all the gross bits are connected, we still won't be able to understand what actually happens and why it works. I suspect this will be the case because the old microscopic will become the new macroscopic and we will realise that there is yet orders of magnitude more details to make sense of.
- nh23423fefe 4y ago
  Explanations can exist at multiple levels. Reducing mind to neurons to atoms doesn't destroy/invalidate the emergent description at higher levels. Just because we "know" the world is "made" of fields doesn't mean that the idea of objects is meaningless.
- pmoriarty 4y ago
  "the old microscopic will become the new macroscopic and we will realise that there is yet orders of magnitude more details to make sense of." That's already the case. Below the neuron level is the molecular level. Below the molecular level is the atomic level. Below the atomic level is the subatomic level. The last of these is still in the process of being explored and understood by physics, and there it might not even be possible to measure all there is at that level, much less make sense of it or adequately model it. As Roger Penrose famously pointed out, events at the subatomic level might be critical for consciousness, and we're very far from modeling even all the molecular interaction that happen in a human brain, nevermind the atomic or subatomic interactions.
abraxas 4y ago
Is it simulated to the level where you could give it some visual stimulus and observe the actions it is trying to take? Could it be wired to a remote robotic insect and control it in real time? I've no idea how detailed these simulation projects and if we are months or decades away from doing what I mentioned
- yyyk 4y ago
  >Is it simulated to the level where you could give it some visual stimulus and observe the actions it is trying to take? No way. First, this mapping doesn't tell us how the synapses are regulated - if we could 'run' this the weights would stay fixed forever and that's not how a brain works. Second, there must be some neurons dedicated to chemical management, and they'd go haywire unless you found a way to deal with them. It's possible the hardware/software is so intertwined it can't be separated. Or maybe it's just complex, regardless the mapping is of limited use here. Third, you're assuming that the synapses/axons are the only thing that matters. It may well be this is true, but having other processes being involved has not yet been entirely ruled out. If they are, the mapping is incomplete. Lastly, we don't have the computational ability just yet to simulate even the mapping itself.
  - BurningFrog 4y ago
    Another approach is to try emulating different models of neurons/synapses/etc, and find models that act similarity to the real organism. Investing the search space, to invent a name, can sometimes be very powerful.
  - falcor84 4y ago
    >Lastly, we don't have the computational ability just yet to simulate even the mapping itself. Could you please explain why not? 548,000 synapses sounds entirely feasible to me.
    - yyyk 4y ago
      Neurons and synapses are incredibly complex. Think you're emulating over 3,000 heterogeneous cores with over half a million links while communication must be low-latency-ish. A third of the links seem to join other links and we don't even know what that does. If there's computation there we'll need even more cores.
FrustratedMonky 4y ago
if you map every single neuron, at what point is it no longer just a 'model' of reality, and is reality. How do we know that the computer model of neurons does not have the same internal awareness as the real neurons?
- causality0 4y ago
  That would require knowledge of how detailed you have to get before going deeper stops altering the performance. I suspect there is no magic line that becomes sapience once you cross it; there's just a smooth slope upwards. Someday we'll have to decide standards of measurement that separate the living from the dead.
- deleted 4y ago
  [deleted]
- notfed 4y ago
  In this case the "map" is simply a set of high-res images, not a computer model. I don't think an image can be aware.
  - FrustratedMonky 4y ago
    Guess I need to find source study. This high level article makes it sound like an actual map, not an image. Based on same type of map that has been made of nematode From article Now, researchers have constructed a detailed map of the neurons and the connections between them in the brain of a larval fruit fly. With 3,016 neurons and 548,000 connections, called synapses
    - notfed 4y ago
      There's no citation, but I am assuming it's this: "A searchable image resource of Drosophila GAL4-driver expression patterns with single neuron resolution. eLife, 2023; 12 DOI: 10.7554/eLife.80660"
      - 4y ago
causality0 4y ago
With 3,016 neurons and 548,000 connections, called synapses, the result is by far the most complex map of a whole brain ever made. It's an impressive achievement but I'm not sure I'd call that a whole brain. It's a larval proto-brain with less than 4% the neurons of an adult fly.
- xipho 4y ago
  Science and Nature are the canonical exaggerators when it comes to headlines. Whole genome, whole mitochondria, complete, total, you name it, there is (nearly?) always an invisible asterisk at the end. When these words are use then Materials and Methods tell you what actually happened. What's completely crazy in this research is the ability to thin-section fly brains. Thousands and thousands of slices _of a fly brain_, good old physical science at the heart, crowd-sourced to connect the dots (though I'm not positive that's the case in this paper). The open-hardware imaging tools used in some studies like this are also super cool- https://openspim.org/ https://openspim.org/.
  - seesawtron 4y ago
    This is an electron microscopy based study, not light microscopy (i.e. SPIM or open-spim). Or did you mean something else?
- moonbreams 4y ago
  larvae behave, they learn, they forage, they do have a brain.
  - causality0 4y ago
    Do they learn? What behaviors make a fruit fly larva more intelligent than a jellyfish?
    - moonbreams 4y ago
      Well granted they're solving quadratic equations, but neither are the adults. For instance, if you expose larvae a rewarding stimulus like sugar along with an odour, they will later be attracted to that odour. That is by definition learning, simple learning, but we have to start somewhere i guess. Interestingly there is some evidence that the memory lasts through to the adult stage, despite the fact that a lot of the brain is actually rewired during pupation.
penny10k 4y ago
[dead]
caxco93 4y ago
It kinda looks like the balloons in the Up movie
jokoon 4y ago
I wish AI scientists would try to work on this instead of machine learning.
- seesawtron 4y ago
  But they are: https://research.google/teams/connectomics/ https://research.google/teams/connectomics/
- simonh 4y ago
  You really believe we’d be better off doing no machine learning research at all?
  - coldtea 4y ago
    Machine learning? We'd be better off with way less technology in general... if we manage to survive tech induced climate change and/or potential nuclear annihilation without billions dying that is...
    - pmoriarty 4y ago
      What about modern medicine, modern agriculture, modern chemistry? Billions would die without those as well.
    - the_third_wave 4y ago
      There are billions of people alive just now because of technology. Poverty is rapidly being eradicated with the help of technology. Child mortality in the third world is rapidly going down due to the spread of technology and the knowledge how to use it. Food production is at an all-time high with the help of technology. The planet is far greener with a far larger forest cover than it was a century ago both due to technological developments which made agriculture far more productive and due to the increased CO₂ concentration in the atmosphere. The potential for nuclear annihilation has kept the (first?) cold war from going hot [1], providing a rare period of detente/relative peace in Europe. This now seems to have come to an end so it is to be hoped that rational minds will prevail where it comes to the use of nuclear weapons as they did for the last ~80 years. Technology has its downsides as well but often it is possible to use more technology to solve problems caused by the use of technology, e.g. filters on smokestacks, fast breeder reactors to solve the problems with nuclear waste, etc. In other words there is a need for more technology, not less. It is also necessary to make technology accessible to more people than it currently is, not by handing out widgets to "the poor" but by enabling those with the will and the capacity to build up their own capacity to produce and use it. It is technology which will solve any problems caused by a changing climate, whether that be a rise or drop in temperature and the resulting effects on precipitation. It is technology which will keep the population from ever increasing to the breaking point simply because people feel the need to have many children since so many of them do not survive past their early years. [1] ...although there have been plenty of proxy wars in Africa, Asia as well as South-America
scarmig 4y ago
> But the study revealed that a third of the connections in the fruit fly’s brain did not follow this pattern—they were between two axons, between two dendrites or from a dendrite to an axon. Interesting. Does this extend to humans? Does it offer a plausible biological mechanism for backprop?
ralusek 4y ago
His name is Timothy Mosca and he works with fruit flies... Mosca means fly, the insect, in Spanish.
- mkmk 4y ago
  Nominative determinism! https://en.wikipedia.org/wiki/Nominative_determinism https://en.wikipedia.org/wiki/Nominative_determinism
  - pfoof 4y ago
    A large digression: "In 2015 researchers Limb, Limb, Limb and Limb published a paper on their study into the effect of surnames on medical specialisation"
andbberger 4y ago
see also: https://www.janelia.org/project-team/flyem/hemibrain https://www.janelia.org/project-team/flyem/hemibrain and a competing effort: https://www.nature.com/articles/s41592-021-01330-0.pdf https://www.nature.com/articles/s41592-021-01330-0.pdf
goatlover 4y ago
It's interesting how much of the fruit fry larva's brain is related to learning, when everyone talks about insect behavior in terms of instinct.
ghirby 4y ago
[flagged]
tomcam 4y ago
But enough about Prince Harry
suction 4y ago
[dead]
stevenjgarner 4y ago
Is it reasonable to expect that as this science progresses, it will progressively map out more complex connectomes? So the connectomes of nematodes and sea squirts have only a few hundred neurons each; and a fruit fly larva has 3,016 neurons with 548,000 synapses; and humans have 86 billion neurons with hundreds of trillions of synapses; is the expectation that brain maps will progressively be made of animals that have: 10k neurons - e.g. leech [1] 100k neurons - e.g. lobster [1] 1M neurons - e.g. cockroach [1] 10M neurons - e.g. zebrafish [1] 100M neurons - e.g. mole-rat [1] 1G neurons - e.g. buzzard [1] 10G neurons - e.g. giraffe [1] [1] https://en.wikipedia.org/wiki/List_of_animals_by_number_of_neurons https://en.wikipedia.org/wiki/List_of_animals_by_number_of_n...
- abecedarius 4y ago
  "Bees: a new unit of measurement for ML model size" https://www.lesswrong.com/posts/YKfNZAmiLdepDngwi/gpt-175bee https://www.lesswrong.com/posts/YKfNZAmiLdepDngwi/gpt-175bee (lists some other animals too)
ouraf 4y ago
The name of one of the scientists involved in mapping a fly's brain is MOSCA? I had to double check if I didn't click on a Babylon bee or the onion article just to be sure.
Slava_Propanei 4y ago
[dead]

278 points by mkmk 4y ago

"With 3,016 neurons and 548,000 connections, called synapses, the result is by far the most complex map of a whole brain ever made." "Researchers have also mapped 25,000 neurons and 20 million synapses in the brain of an adult fruit fly, but this is still just a partial [map]" "Human brains have an estimated 86 billion neurons and hundreds of trillions of synapses" The scales at play here are hard to imagine. This is very interesting but it seems the most interesting facet is the completeness, and not just the absolute scale.

GordonS 4y ago

> The connectome of the larval fly, published Friday in the journal Science, took 12 years to complete. Imaging a single neuron required about a day... > Human brains have an estimated 86 billion neurons and hundreds of trillions of synapses... So, the techniques used for the fly are totally impractical for humans, or presumably any mammal. Anyone know of any developments that may help? Maybe AI could be used to automate processing of the images?

kuprel 4y ago
“If the human brain were so simple that we could understand it, we would be so simple that we couldn’t.” Maybe AI can though
- notfed 4y ago
  Asking AI to map human brains...what could possibly go wrong?
dredog 4y ago
Yep, this is already happening. I think it’s called ‘automatic segmentation’.
undersuit 4y ago
Do we need to image all 86 billion? A sampling of cells throughout the brain and a simulation of a cell such that we can figure out how 1 fertilized egg can become 86 billion neurons and change. We can throw compute power at that, we don't really have brains to throw at the problem.
inportb 4y ago
More like totally impractical for living specimens that you want to continue living meaningfully.
moonbreams 4y ago
The sell with this kind of research is that doing it will lead to order of magnitude gains in complexity - compare the time it took to sequence the first fruit fly genome with the time it takes today

usgroup 4y ago

i intuitively think that there is something similar in kind between a fruit fly brain and a human brain regardless of the scale, and that cracking the smaller case will somehow lead to cracking the larger one. However, rather than hope, it leads me to a negative conclusion. That is, even at orders of magnitude smaller scales, and with full knowledge of how all the gross bits are connected, we still won't be able to understand what actually happens and why it works. I suspect this will be the case because the old microscopic will become the new macroscopic and we will realise that there is yet orders of magnitude more details to make sense of.

nh23423fefe 4y ago
Explanations can exist at multiple levels. Reducing mind to neurons to atoms doesn't destroy/invalidate the emergent description at higher levels. Just because we "know" the world is "made" of fields doesn't mean that the idea of objects is meaningless.
pmoriarty 4y ago
"the old microscopic will become the new macroscopic and we will realise that there is yet orders of magnitude more details to make sense of." That's already the case. Below the neuron level is the molecular level. Below the molecular level is the atomic level. Below the atomic level is the subatomic level. The last of these is still in the process of being explored and understood by physics, and there it might not even be possible to measure all there is at that level, much less make sense of it or adequately model it. As Roger Penrose famously pointed out, events at the subatomic level might be critical for consciousness, and we're very far from modeling even all the molecular interaction that happen in a human brain, nevermind the atomic or subatomic interactions.

abraxas 4y ago

Is it simulated to the level where you could give it some visual stimulus and observe the actions it is trying to take? Could it be wired to a remote robotic insect and control it in real time? I've no idea how detailed these simulation projects and if we are months or decades away from doing what I mentioned

yyyk 4y ago
>Is it simulated to the level where you could give it some visual stimulus and observe the actions it is trying to take? No way. First, this mapping doesn't tell us how the synapses are regulated - if we could 'run' this the weights would stay fixed forever and that's not how a brain works. Second, there must be some neurons dedicated to chemical management, and they'd go haywire unless you found a way to deal with them. It's possible the hardware/software is so intertwined it can't be separated. Or maybe it's just complex, regardless the mapping is of limited use here. Third, you're assuming that the synapses/axons are the only thing that matters. It may well be this is true, but having other processes being involved has not yet been entirely ruled out. If they are, the mapping is incomplete. Lastly, we don't have the computational ability just yet to simulate even the mapping itself.
- BurningFrog 4y ago
  Another approach is to try emulating different models of neurons/synapses/etc, and find models that act similarity to the real organism. Investing the search space, to invent a name, can sometimes be very powerful.
- falcor84 4y ago
  >Lastly, we don't have the computational ability just yet to simulate even the mapping itself. Could you please explain why not? 548,000 synapses sounds entirely feasible to me.
  - yyyk 4y ago
    Neurons and synapses are incredibly complex. Think you're emulating over 3,000 heterogeneous cores with over half a million links while communication must be low-latency-ish. A third of the links seem to join other links and we don't even know what that does. If there's computation there we'll need even more cores.

FrustratedMonky 4y ago

if you map every single neuron, at what point is it no longer just a 'model' of reality, and is reality. How do we know that the computer model of neurons does not have the same internal awareness as the real neurons?

causality0 4y ago
That would require knowledge of how detailed you have to get before going deeper stops altering the performance. I suspect there is no magic line that becomes sapience once you cross it; there's just a smooth slope upwards. Someday we'll have to decide standards of measurement that separate the living from the dead.
deleted 4y ago
[deleted]
notfed 4y ago
In this case the "map" is simply a set of high-res images, not a computer model. I don't think an image can be aware.
- FrustratedMonky 4y ago
  Guess I need to find source study. This high level article makes it sound like an actual map, not an image. Based on same type of map that has been made of nematode From article Now, researchers have constructed a detailed map of the neurons and the connections between them in the brain of a larval fruit fly. With 3,016 neurons and 548,000 connections, called synapses
  - notfed 4y ago
    There's no citation, but I am assuming it's this: "A searchable image resource of Drosophila GAL4-driver expression patterns with single neuron resolution. eLife, 2023; 12 DOI: 10.7554/eLife.80660"
    - 4y ago

causality0 4y ago

With 3,016 neurons and 548,000 connections, called synapses, the result is by far the most complex map of a whole brain ever made. It's an impressive achievement but I'm not sure I'd call that a whole brain. It's a larval proto-brain with less than 4% the neurons of an adult fly.

xipho 4y ago
Science and Nature are the canonical exaggerators when it comes to headlines. Whole genome, whole mitochondria, complete, total, you name it, there is (nearly?) always an invisible asterisk at the end. When these words are use then Materials and Methods tell you what actually happened. What's completely crazy in this research is the ability to thin-section fly brains. Thousands and thousands of slices _of a fly brain_, good old physical science at the heart, crowd-sourced to connect the dots (though I'm not positive that's the case in this paper). The open-hardware imaging tools used in some studies like this are also super cool- https://openspim.org/ https://openspim.org/.
- seesawtron 4y ago
  This is an electron microscopy based study, not light microscopy (i.e. SPIM or open-spim). Or did you mean something else?
moonbreams 4y ago
larvae behave, they learn, they forage, they do have a brain.
- causality0 4y ago
  Do they learn? What behaviors make a fruit fly larva more intelligent than a jellyfish?
  - moonbreams 4y ago
    Well granted they're solving quadratic equations, but neither are the adults. For instance, if you expose larvae a rewarding stimulus like sugar along with an odour, they will later be attracted to that odour. That is by definition learning, simple learning, but we have to start somewhere i guess. Interestingly there is some evidence that the memory lasts through to the adult stage, despite the fact that a lot of the brain is actually rewired during pupation.

penny10k 4y ago

[dead]

caxco93 4y ago

It kinda looks like the balloons in the Up movie

jokoon 4y ago

I wish AI scientists would try to work on this instead of machine learning.

seesawtron 4y ago
But they are: https://research.google/teams/connectomics/ https://research.google/teams/connectomics/
simonh 4y ago
You really believe we’d be better off doing no machine learning research at all?
- coldtea 4y ago
  Machine learning? We'd be better off with way less technology in general... if we manage to survive tech induced climate change and/or potential nuclear annihilation without billions dying that is...
  - pmoriarty 4y ago
    What about modern medicine, modern agriculture, modern chemistry? Billions would die without those as well.
  - the_third_wave 4y ago
    There are billions of people alive just now because of technology. Poverty is rapidly being eradicated with the help of technology. Child mortality in the third world is rapidly going down due to the spread of technology and the knowledge how to use it. Food production is at an all-time high with the help of technology. The planet is far greener with a far larger forest cover than it was a century ago both due to technological developments which made agriculture far more productive and due to the increased CO₂ concentration in the atmosphere. The potential for nuclear annihilation has kept the (first?) cold war from going hot [1], providing a rare period of detente/relative peace in Europe. This now seems to have come to an end so it is to be hoped that rational minds will prevail where it comes to the use of nuclear weapons as they did for the last ~80 years. Technology has its downsides as well but often it is possible to use more technology to solve problems caused by the use of technology, e.g. filters on smokestacks, fast breeder reactors to solve the problems with nuclear waste, etc. In other words there is a need for more technology, not less. It is also necessary to make technology accessible to more people than it currently is, not by handing out widgets to "the poor" but by enabling those with the will and the capacity to build up their own capacity to produce and use it. It is technology which will solve any problems caused by a changing climate, whether that be a rise or drop in temperature and the resulting effects on precipitation. It is technology which will keep the population from ever increasing to the breaking point simply because people feel the need to have many children since so many of them do not survive past their early years. [1] ...although there have been plenty of proxy wars in Africa, Asia as well as South-America

scarmig 4y ago

> But the study revealed that a third of the connections in the fruit fly’s brain did not follow this pattern—they were between two axons, between two dendrites or from a dendrite to an axon. Interesting. Does this extend to humans? Does it offer a plausible biological mechanism for backprop?

ralusek 4y ago

His name is Timothy Mosca and he works with fruit flies... Mosca means fly, the insect, in Spanish.

mkmk 4y ago
Nominative determinism! https://en.wikipedia.org/wiki/Nominative_determinism https://en.wikipedia.org/wiki/Nominative_determinism
- pfoof 4y ago
  A large digression: "In 2015 researchers Limb, Limb, Limb and Limb published a paper on their study into the effect of surnames on medical specialisation"

andbberger 4y ago

see also: https://www.janelia.org/project-team/flyem/hemibrain https://www.janelia.org/project-team/flyem/hemibrain and a competing effort: https://www.nature.com/articles/s41592-021-01330-0.pdf https://www.nature.com/articles/s41592-021-01330-0.pdf

goatlover 4y ago

It's interesting how much of the fruit fry larva's brain is related to learning, when everyone talks about insect behavior in terms of instinct.

ghirby 4y ago

[flagged]

tomcam 4y ago

But enough about Prince Harry

suction 4y ago

[dead]

stevenjgarner 4y ago

Is it reasonable to expect that as this science progresses, it will progressively map out more complex connectomes? So the connectomes of nematodes and sea squirts have only a few hundred neurons each; and a fruit fly larva has 3,016 neurons with 548,000 synapses; and humans have 86 billion neurons with hundreds of trillions of synapses; is the expectation that brain maps will progressively be made of animals that have: 10k neurons - e.g. leech [1] 100k neurons - e.g. lobster [1] 1M neurons - e.g. cockroach [1] 10M neurons - e.g. zebrafish [1] 100M neurons - e.g. mole-rat [1] 1G neurons - e.g. buzzard [1] 10G neurons - e.g. giraffe [1] [1] https://en.wikipedia.org/wiki/List_of_animals_by_number_of_neurons https://en.wikipedia.org/wiki/List_of_animals_by_number_of_n...

abecedarius 4y ago
"Bees: a new unit of measurement for ML model size" https://www.lesswrong.com/posts/YKfNZAmiLdepDngwi/gpt-175bee https://www.lesswrong.com/posts/YKfNZAmiLdepDngwi/gpt-175bee (lists some other animals too)

ouraf 4y ago

The name of one of the scientists involved in mapping a fly's brain is MOSCA? I had to double check if I didn't click on a Babylon bee or the onion article just to be sure.

Slava_Propanei 4y ago

[dead]