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The circuit that lets your brain think and see

engineering.columbia.edu

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Re: The circuit that lets your brain think and see

#11

Post by willy_k »

milleramp wrote: post #7
w10-1 wrote: post #4

Paper title: Disinhibitory signaling enables flexible coding of top-down information in cortical networks (should be qualified as in-silico visual systems) Method: replicate fMRI findings of visual abstraction using simple networks to model what's essential Gist: in tasks 'Inhibitory neurons that suppress other inhibitory neurons seem to pass key information from the “thinking” part of the system to the “sensing” com…

"inhibition fails" reminded me of this passage from Fear and Loathing. "Ah, devil ether. It makes you behave like the village drunkard in some early Irish novel... total loss of all basic motor skills. Blurred vision, no balance, numb tongue. The mind recoils in horror, unable to communicate with the spinal column."

It’s worth noting that in neuro speak, inhibition does not necessarily correlate with what would appear to be a “dis/inhibited” person; it’s referring to a specific process where signals are blocked from propagating, and because the brain is made of a complex web of inter-modulatory loops, this can show up in unintuitive ways

e.g. signals from the default mode network getting in the way of task-oriented behavior, which can result in people appearing “inhibited” where in actuality they’re failing to inhibit irrelevant internal signals and (errant bottom-up) attention to them (this is the case in ADHD).

Re: The circuit that lets your brain think and see

#12

Post by nomel »

agumonkey wrote: post #10
w10-1 wrote: post #4

Paper title: Disinhibitory signaling enables flexible coding of top-down information in cortical networks (should be qualified as in-silico visual systems) Method: replicate fMRI findings of visual abstraction using simple networks to model what's essential Gist: in tasks 'Inhibitory neurons that suppress other inhibitory neurons seem to pass key information from the “thinking” part of the system to the “sensing” com…

I'm very curious about inhibition failures in brain areas, especially between visual perception and motor control. I'm no neurologist but your brain seems to generate a lot of imaginary interpretation when sensing the visual field, but sometimes there are short circuit like failure that leak those potential imaginary futures with you current real self (leading to strange uncoordinated or overlapping motor control sig…

Imbalance of inhibitory and excitatory appears to be the definition/state of a seizure.

Apparently, this even goes both directions, as there are also inhibitory seizures, leading to temporary paralysis! [1]

[1] https://www.medlink.com/articles/inhibitory-motor-seizures

Re: The circuit that lets your brain think and see

#13

Post by taneq »

willy_k wrote: post #11
milleramp wrote: post #7

Earlier quoted context omitted.

"inhibition fails" reminded me of this passage from Fear and Loathing. "Ah, devil ether. It makes you behave like the village drunkard in some early Irish novel... total loss of all basic motor skills. Blurred vision, no balance, numb tongue. The mind recoils in horror, unable to communicate with the spinal column."

It’s worth noting that in neuro speak, inhibition does not necessarily correlate with what would appear to be a “dis/inhibited” person; it’s referring to a specific process where signals are blocked from propagating, and because the brain is made of a complex web of inter-modulatory loops, this can show up in unintuitive ways e.g. signals from the default mode network getting in the way of task-oriented behavior, whi…

Think of it like a relay with a normally closed contact.

Re: The circuit that lets your brain think and see

#14

Post by ekelsen »

The actual experiment is basically training a relatively large RNN (1000 units) to do a very simple copy-esque task. The weight values are constrained to be either positive or negative at the beginning of training. The RNN could probably be way smaller and still be made to solve this task.

It isn't even a spiking model.

It seems really hard to go from this experiment to "we've learned anything useful about how brains actually work."

https://www.biorxiv.org/content/10.1101/2023.10.17.562828v2....

Re: The circuit that lets your brain think and see

#17

Post by jibal »

"Compare the brain to something like ChatGPT or a large language model. We can do far more, across far more situations, on a tiny fraction of the energy — and without being trained on the whole internet. The brain got there through evolution, through the redundancy built into its wiring. Our models are recurrent neural networks, which are quite different from the transformers behind today's large language models. The goal is to work out these principles one by one and use them to make AI leaner and more adaptive. This inhibition-on-inhibition motif is one of them."

Cool!

Re: The circuit that lets your brain think and see

#19

Post by MajorTakeaway »

w10-1 wrote: post #4

Paper title: Disinhibitory signaling enables flexible coding of top-down information in cortical networks (should be qualified as in-silico visual systems) Method: replicate fMRI findings of visual abstraction using simple networks to model what's essential Gist: in tasks 'Inhibitory neurons that suppress other inhibitory neurons seem to pass key information from the “thinking” part of the system to the “sensing” com…

See I did what I saw when doing a task like grabbing for my Guinness to take a swig and ended up hitting my laptop with the bottle when I brought the bottle to my body.

Maybe I have a bit of inhibition going on there.

Re: The circuit that lets your brain think and see

#20

Post by agumonkey »

nomel wrote: post #12
agumonkey wrote: post #10

Earlier quoted context omitted.

I'm very curious about inhibition failures in brain areas, especially between visual perception and motor control. I'm no neurologist but your brain seems to generate a lot of imaginary interpretation when sensing the visual field, but sometimes there are short circuit like failure that leak those potential imaginary futures with you current real self (leading to strange uncoordinated or overlapping motor control sig…

Imbalance of inhibitory and excitatory appears to be the definition/state of a seizure. Apparently, this even goes both directions, as there are also inhibitory seizures , leading to temporary paralysis! [1] [1] https://www.medlink.com/articles/inhibitory-motor-seizures

Thanks a lot
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