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What does the cerebellum do?

sarahconstantin.substack.com

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Re: What does the cerebellum do?

#101

Post by plufz »

akavi wrote: post #81

This is fascinating to me. The list of things the author suggests the cerebellum handles is a tailor-made list of things I'm oddly bad at: 1. I'm very uncoordinated, with a noticeable intentional tremor 2. I'm particularly bad at sequencing dependencies for projects/errands/household tasks. I have to write down even fairly simple sequences of subtasks or get lost in yak-shaving loops 3. When flustered, I make very di…

Often with the brain multiple regions are needed for a single function. For example planing action including movement has much to do with the prefrontal cortex and the basal ganglia is much involved in making smooth motions and inhibiting tremors, etc. Problems with the dopamine system also affect things like planing (ADHD) and tremors (Parkinson’s).

Re: What does the cerebellum do?

#102

Post by astrange »

Spooky23 wrote: post #70
p1necone wrote: post #40

Earlier quoted context omitted.

$800,000 is a lot of money, even after taxes you'd only have to work a few years at that salary before you could live reasonably comfortably for the rest of your life without working at all. Seems perfectly reasonably to switch to a lower stress career at some point.

The personalities attracted to the role aren’t really amenable to thinking that way.

There's also lifestyle inflation, and of course retiring early rarely impresses your spouse.

Re: What does the cerebellum do?

#103

Post by cubefox »

im3w1l wrote: post #50
cubefox wrote: post #12

So classical conditioning in humans requires special cells in the Cerebellum (Purkinje cells), which can even do single-cell learning. Which artificial neurons can't do, as only weights (artificial synapses) are updated. So how is classical conditioning actually implemented in artificial neural networks? I assume there is some minimum network which makes it work.

Well classical conditioning kind of only makes sense in the context of an agent that is receiving inputs and taking actions on them. Many neural networks don't solve problems of that type, and so have no need for classical conditioning. But when you do have such a problem conditioning is not very complicated. The normal algorithms and neural structures are designed to learn stuff like "when a given input happens a ce…

Yeah. It's just not quite clear what the minimal example for such a network would be. I assume you have N inputs and one output. The output always active when input 1 is active, otherwise the output is inactive. So the other inputs are ignored. However, when one of those other inputs, x, tends to be temporally correlated with input 1, after a while x will generate an output upon activation even if input 1 isn't active. If x becomes decorrelated with input 1, x will again get ignored. Not sure what the simplest network architecture looks like that implements this behavior.

Re: What does the cerebellum do?

#104

Post by Terr_ »

retrac wrote: post #21
padolsey wrote: post #11

What a marvellous article. One thing I’ve never quite appreciated in neuroscience is how useful physical movement is as a debugging layer. During a task, in observing gaits, tremors, speed, accuracy, etc., you’re able to gain a deeper understanding of how cognition works for non-movement tasks. I guess cognition is, after all, still just movement, but through a conceptual plane instead of a physical one.

It's been argued that most, maybe all, of human cognition is based on a sort of folk-physics mental model with objects. We throw ideas into the ring to be chewed on and distilled and maybe brought in to practice or thrown out as useless. The linguistic metaphors we use, at least, to talk about ideas and abstractions, are never more than one, maybe two, steps away from a hand moving or rearranging something.

> folk-physics mental model with objects

Kind of like how object permanence [0] must be learned by babies, slowly worked into their internal model, even though "things don't usually vanish when they go behind other things" seems like reliably low-hanging fruit for any process (whether evolutionary or meddling demigod) to wire up as instinctual physics knowledge.

[0] https://en.wikipedia.org/wiki/Object_permanence

Re: What does the cerebellum do?

#105

Post by bsdpufferfish »

red75prime wrote: post #99
bsdpufferfish wrote: post #87

Earlier quoted context omitted.

Even if you are a full materialist it's fallacious to assume there is one "part" that does something, like it's a factory assembly. Instead it might be a function of the composition of brain parts. It's like asking which part of a bat makes it fly. The wings? Well kind of, but you need more than that. I guess you can fly without feet... it's just not a well formed question.

If you ask question a bit differently, then it's not a mystery at all. Why brain parts that have neural structure, which is conductive to fine and agile motor control, perform motor control?

Why is it in a part? Which part of the violin makes it sound in tune?

Re: What does the cerebellum do?

#108

Post by dragonwriter »

bsdpufferfish wrote: post #87
doug_durham wrote: post #86

Earlier quoted context omitted.

Are you suggesting a metaphysical structure? I don't understand what you are getting at.

Even if you are a full materialist it's fallacious to assume there is one "part" that does something, like it's a factory assembly. Instead it might be a function of the composition of brain parts. It's like asking which part of a bat makes it fly. The wings? Well kind of, but you need more than that. I guess you can fly without feet... it's just not a well formed question.

> Even if you are a full materialist it's fallacious to assume there is one "part" that does something, like it's a factory assembly. Instead it might be a function of the composition of brain parts.

Its true that a particular function may mot be localizable more specifically than the brain (or even the whole body), because defining it as a distinct function may not reflect the organization of conponents within the body. But that's still performed by a defined physical system, and there are still sub-functions necessary to perform that function that are localizable to narrower components.

> It's like asking which part of a bat makes it fly.

Its like that in that we absolutely can describe specific parts of the bat and what each contributes to flight.

Re: What does the cerebellum do?

#109

Post by solax »

That's an interesting perspective. While I agree that the pace of advancements in neuroscience is slower compared to AI, I think it's important to note that understanding the brain is a fundamentally different problem than building intelligent machines. The human brain is an incredibly complex system with billions of interconnected neurons, and we still have a long way to go in terms of fully understanding how it works.

AI, on the other hand, is designed to solve specific problems efficiently, and it can be engineered to mimic certain aspects of human cognition without necessarily needing to understand the underlying mechanisms.

While it's possible that AI could eventually help us better understand the brain, I believe that advancements in neuroscience will continue to be crucial for unlocking the full potential of AI. Understanding how the brain processes information, learns, and makes decisions could lead to the development of more sophisticated and human-like AI systems.

Re: What does the cerebellum do?

#110

Post by eurekin »

woadwarrior01 wrote: post #27

> In total, the cerebellum contains 80% of all neurons! Apples and oranges, but that's so reminiscent of MLPs in Transformers. A similarly large fraction of the weights in transformers come from the MLPs in each layer.

Well, MLPs is the actual neural network (the approximator), whereas the attention (the rest) is more of a text to relevant embedding extractor
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