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An adult fruit fly brain has been mapped

economist.com

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Re: An adult fruit fly brain has been mapped

#181

Post by eternauta3k »

awestroke wrote: post #156

Related: my favorite HN comment ever from a similar submission a year ago: > There's lots of very exciting work going on around the fully mapped fruit fly connectome. For example, I'm a CTO of a stealth startup that aims to do for utilitarianism what carbon credits did for environmentalism. We are selling 'utility credits' which translates directly into us simulating trillions and trillions of fruit fly brains in a s…

Why do you actually need to simulate them? The mapping between the state of the computer and the simulated state it represents exists only in our heads. You might as well say that any reality you can vaguely conceive of, exists and has moral weight.

Re: An adult fruit fly brain has been mapped

#182

Post by physicsguy »

bumby wrote: post #170
neverrroot wrote: post #162

Earlier quoted context omitted.

About as useful as the carbon credits themselves

Curious if you could elaborate? It seems like the issue isn’t carbon credits, but the lack of a regulated level of carbon that would make them effective. Market incentives work best with dollar incentives, not virtue points.

I interviewed with a company a few years ago that offers people the ability to certify their carbon free generation in countries where there isn’t a regulated market (I.e. outside of the US, EU, etc.). I was pretty shocked by the low standards of proof required, and it’s fairly obvious that someone can seek accreditation from multiple competing certifying agencies.

These unregulated credits get bought by heavy consumers in greenwashing

Re: An adult fruit fly brain has been mapped

#184

Post by FrustratedMonky »

FrustratedMonky wrote: post #158
awestroke wrote: post #156

Related: my favorite HN comment ever from a similar submission a year ago: > There's lots of very exciting work going on around the fully mapped fruit fly connectome. For example, I'm a CTO of a stealth startup that aims to do for utilitarianism what carbon credits did for environmentalism. We are selling 'utility credits' which translates directly into us simulating trillions and trillions of fruit fly brains in a s…

They have a branding opportunity. Karma Kredits Perhaps a co-branding opportunity with Krispy Kreme donuts? Buy a donut, and experience some Joy, which handily comes with Karma Kredits to offset that Joy. Have some KK with the KK!

Wash away the guilt of one-too-many Krispy Kreme with some Karma Kredits.

Re: An adult fruit fly brain has been mapped

#185

Post by andbberger »

rmorey wrote: post #123
andbberger wrote: post #95

Earlier quoted context omitted.

the raw data will be on the order of PBs

the EM dataset for this connectome, FAFB, is only a few hundred TB. as a rule of thumb volume electron microscopy datasets are on the order of 1 PB / cubic millimeter, and the fly brain is much smaller than 1 mm3

a few hundred TB is on the order PBs

Re: An adult fruit fly brain has been mapped

#186

Post by danbruc »

Do we understand how memory works in general? If you tell me to remember the number 71, I can do that instantly with my short term memory, so I would guess that works without any changes to the brain structure and more like charging or discharging the tiny capacity in a DRAM cell or flipping the feedback loop in an SRAM cell. For long term memory on the other hand I would assume that this involves changes to the brain structure as this seems more robust but slower to do, I would have to think of 71 for quite some time in order to remember it weeks, months or years later. Do we know anything about this in good detail or is this still too hard to investigate because the relevant structures or processes are hidden in a sea of other things?

Re: An adult fruit fly brain has been mapped

#187

Post by achileas »

danbruc wrote: post #186

Do we understand how memory works in general? If you tell me to remember the number 71, I can do that instantly with my short term memory, so I would guess that works without any changes to the brain structure and more like charging or discharging the tiny capacity in a DRAM cell or flipping the feedback loop in an SRAM cell. For long term memory on the other hand I would assume that this involves changes to the brai…

We don't really know much about how memories are formed, the short-term and long-term divisions come from cognitive psychology and we don't have (from what I remember from my neuro days, which may be out of date by now but I am friends with several neuroscientists and I'm not sure it's out of date yet) a strong idea of what the biological correlates of each are, or even if they arise via different processes or what.

Re: An adult fruit fly brain has been mapped

#188

Post by achileas »

hwillis wrote: post #155
mr_toad wrote: post #108

Earlier quoted context omitted.

It’s a neural network without weights. And it doesn’t have a body. Figuring out the behaviour of the neurons could take decades, although I have no doubt that people will eventually. And simulating a whole fruit fly body seems like it’s going to be out of reach for a very long time.

> It’s a neural network without weights. It has approximate weights. Neuron connection strength is determined by the number of synapses (1-100s, sometimes 1000s), the type of synapse neurotransmitter, and the number of receptors. The connectome has 1 and 2 and is only missing 3. The number of receptors may not even be that important- the fact that the number of synapses is important may well mean the number of recept…

And of course, not just frequency of incoming action potentials, but processes within the receiving cell, in the cell membrane, at the site of the synapse, and between the cell and any supporting cells (astrocytes and glia).

It's also not just frequency, but "shape" (for lack of a better word) of incoming inputs that matters, as such there is a very wide variety of spiking patterns that certain cells exhibit, like chopper cells.

Re: An adult fruit fly brain has been mapped

#189

Post by LukaD »

neverrroot wrote: post #162
awestroke wrote: post #156

Related: my favorite HN comment ever from a similar submission a year ago: > There's lots of very exciting work going on around the fully mapped fruit fly connectome. For example, I'm a CTO of a stealth startup that aims to do for utilitarianism what carbon credits did for environmentalism. We are selling 'utility credits' which translates directly into us simulating trillions and trillions of fruit fly brains in a s…

About as useful as the carbon credits themselves

Yes, that was the joke.

Re: An adult fruit fly brain has been mapped

#190

Post by glenstein »

eternauta3k wrote: post #181
awestroke wrote: post #156

Related: my favorite HN comment ever from a similar submission a year ago: > There's lots of very exciting work going on around the fully mapped fruit fly connectome. For example, I'm a CTO of a stealth startup that aims to do for utilitarianism what carbon credits did for environmentalism. We are selling 'utility credits' which translates directly into us simulating trillions and trillions of fruit fly brains in a s…

Why do you actually need to simulate them? The mapping between the state of the computer and the simulated state it represents exists only in our heads. You might as well say that any reality you can vaguely conceive of, exists and has moral weight.

Depending on which article you look at, you can see things such as the stunning, vivid rotating 3D model showing the optic lobes, or elaborations on what the model captures: it has mapped 139,000 neurons and 130 million synapses. I don't think that quietly picturing a fruit fly in your head executes a true simulation of those details.

I do think, in some cases, there is such a thing as thinking being equivalent to simulating (e.g. a calculator) but this isn't one of those.

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