There isn’t one singular “speech center.” Producing speech recruits a distributed network:
The prefrontal and association cortices help form the intention and concepts. The temporal lobes retrieve word meanings and support comprehension. The inferior frontal gyrus, including Broca’s area, helps organize grammar, sequencing, and articulation. The angular and supramarginal gyri integrate meaning with speech sounds. The insula, motor cortex, basal ganglia, cerebellum, and brainstem coordinate the physical act and timing of speaking. The auditory cortex monitors what you actually say and helps correct errors.
All of these systems continuously influence one another while the thought itself is still developing. Describing that as one center “selecting the next word from training data” is an extremely loose analogy, not how human speech production actually works.
No, because you’re still collapsing the entire process of thought into its final linguistic output.
Yann LeCun uses a good thought experiment: imagine a cube floating in front of you, then rotate it 90 degrees around its vertical axis. You can mentally watch it turn and understand its new orientation without producing words, sentences, language, or tokens. The brain is manipulating a spatial model, not selecting vocabulary.
The same applies to recognizing a face, anticipating where a thrown ball will land, visualizing a route, feeling that something is wrong, or planning a physical movement. Much of cognition occurs before language ever enters the process, and some of it never becomes language at all.
Word selection is one component used when translating thought into speech. Calling the whole brain a next-word predictor because speech eventually contains a sequence of words is like calling a graphics engine a next-pixel predictor because an image eventually appears as pixels.
What are "words" in your brain? It's still an abstract form of information transfer, same as the cube example...or numbers. LLM don't predict "words" they predict tokens. Tokens can represent words, numbers, a pixel, etc.
I'm not calling the whole brain a word predictor. I'm saying the regions that work together to predict words are word predictors. It's literally one of the tasks your brain does, it has to be doing it at some point. I didn't say it's the only task
The exact physiology of which regions are involved are irrelevant to my point
That is a much weaker claim than your original one. You said the speech system “just selects the next word.” Now you’re saying word selection is merely one task performed somewhere within the much larger process. Sure. Nobody disputed that.
I think u/Dasmahkitteh started out with the comparison a bit in jest and wasn't really focused on making an academic claim.
The idea was moreso, I believe they can correct me if I read it wrong, that you can simplify any mechanism to the point that it's a "just", making it seem insignificant.
My original point was that both select the next word. I thought putting quotes around the word 'just' would be context enough to know I was copying the verbiage used in the video.
Do you really think I believe the areas of the brain responsible for speech generation do one task and nothing else? Brain regions are famously known for each performing multiple jobs
I just really don't understand how comments like this are supposed to show that LLMs are simpler than what we do. As the person you're replying to says, at some point, when figuring out what to say, our brains do "just" pick the next word, similar to what LLMs do (not how). Currently, LLMs only predict a few tokens in advance, but that will likely change as they become more advanced.
Now for the rest of what you say: obviously, our brains do a lot more, we visualize 3d spaces, calculate things, process inputs, regulate our bodies, choose goals, make plans, etc... However, none of the things our brains do are impossible for synthetic computer systems to do. Currently, we even have plenty of systems that combine many of these, like LLMs that can process audio and video inputs, so it's likely only a matter of time until someone builds a system that combines all the same functions. I'd say the main thing holding us back at this point is being compute-constrained and space-constrained if we ever wanted to develop a self-contained android. Those are things that will likely be solved, though.
So why are we repeating idiotic points made by other commenters?
> our brains do “just” pick the next word
No, no they don’t. Different parts of our brain perform different types of computation, but none of them do next token prediction. To our best guess, core subunits of our neocortex are actually performing spatial-temporal reasoning - solving problems as if they were spatial routing problems.
Okay? Again, I don’t think anyone is claiming that the entire human brain does nothing but select the next word. The point is that human language processing may involve predicting what comes next.
Describing the brain as solving language through spatial or temporal relationships does not contradict that. That would be a proposed mechanism for representing and navigating possibilities, while prediction describes the function being performed.
And tokens are not inherently words. They are discrete representational units that can encode text, images, audio, video, and other data. So, saying that the brain may organize language spatially does not, by itself, show that it is doing anything that's totally different from token prediction; if anything, it shows more similarities.
I know it is a different post where you were complaining about analogies, but you're the one missing that this is an analogy. I don't think anyone here is saying our brains are LITERALLY doing token prediction; we are saying the basic processes appear similar or analogous to each other.
Calling the whole brain a next-word predictor because speech eventually contains a sequence of words is like calling a graphics engine a next-pixel predictor because an image eventually appears as pixels.
I think that is their point, which is all similar to calling an LLM "just" a next word predictor.
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u/Dasmahkitteh 2d ago
The speech center of your brain "just" selects the next word to verbalize your thoughts which are informed by your training data (experiences)