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How deep is the brain? The shallow brain hypothesis

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Re: How deep is the brain? The shallow brain hypothesis

#181
post #169
post #115

I seem to remember research stating that an individual neuron has very complex behaviour that requires several ML “neurons” / nodes to simulate. So if you do a comparison, perhaps the brain is deeper than you’d think by just looking at the graph of neurons and their synapses. Could we construct a neutral net from nodes with more complex behaviour? Probably, but in computing we’ve generally found that it’s best to bui…

Yeah, biological brains could be remarkably more powerful than digital neural networks if the have primitive functions that we haven't accounted for. For example, some networks seem to encode information in the firing rate , rather than just the presence of a signal. If neurons could, e.g. do frequency-based calculations (and not just threshold-based, like spiking neural nets), they could be orders of magnitude more…

My guess is that the firing rate of biological neurons more or less simplifies to the activation in an artificial neuron. Higher firing rate = higher activation.

Re: How deep is the brain? The shallow brain hypothesis

#182
post #17
post #8

Earlier quoted context omitted.

When you say “massive amount of energy” are you comparing the energy requirements to a single human or to the billions of years of solar and geothermal energy that went into producing the human species?

By that token the amount of energy for neural networks will be bound to some extent by the development of the biosphere and the creators of neural networks.

See “The last question” for some sci-fi solutions to this.

Re: How deep is the brain? The shallow brain hypothesis

#183
post #34

Earlier quoted context omitted.

I don’t think this is an apt comparison, but I do think the amount of energy it takes to grow a human into brain maturity in adulthood is an interesting one. Brains + bodies over a 20 year development cycle is still probably much less than training even a low quality Llm.

Let’s say a human needs an average of 2000 calories a day. A calorie is roughly equivalent to 1 Watt hour, so over 20 years, it takes about 15 MWh to sustain a human. Let’s say a single A100 has a peak power draw of 250W, and you need 100 to train an LLM. So each hour of training consumes 25,000 Wh of energy. 15 MWh / 25,000 W = 600 hours, or 25 days, which is probably pretty close to the true training time. So the n…

It's probably taking the analogy too far, but perhaps the brain's predefined structure is akin to the original LLM training and our "life" is the fine tuning.

I wonder how many MWh the entirety of evolution represents.

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