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> I believe the "specialized brain regions" idea has been over-debunked. It was the source of so much woo woo in the late 20th century (are you right-brained or left-brained!?) that we've come to think it's complete bunk.

I still see PopSci articles with a title along the lines of; "Scientists have discovered the part of the brain responsible for X". Even in studies or experiments in the literature, I still see color gradient scales used for fMRI. These are known to vastly over exaggerate the discrepancy between functional areas. And yet they allow for a more easily digestible view of what the study is after, which is probably why they're still used.

I think what the author is getting at is that, yes, some parts of the brain are more specialized than others. But there is no specific part of the brain that regulates a specific function and nothing else. Rather, it's an enormously complex system.

edit: Color gradient scales are fine for academic studies and research. However, they can be misleading to laypeople.

And remember that those pictures are themselves the result of lots and lots of clustering and dimension reduction, so are about as useful as cluster analysis of unsupervised data (which is what they are), that is not particularly useful at all.

I mean, the actual problem is that fMRI is expensive, and gives good spatial understanding, but bad temporal understanding (i may be mixing this up, I haven't seriously looked at any brain research in about a decade).

The statistical problems in fMRI are sadly unappreciated, much like the statistical problems in human research more generally.

>This is not a rebuttal to the myth. Imagine I'm talking about a car,

You're simply asserting that the car is analogous to the brain to make an argument. Humans designed the car and fully understand how it works. If you take out the engine - it doesn't run. The brain is not the same - tons of evidence of neural plasticity. There is simply no analogy here. Also, the author is a subject matter expert in cognitive neuroscience so they do have credibility IMO.

>But we have a huge body of evidence showing that there is a big difference in how the left vs. right brain processes information and that different brain regions are highly specialized, but that their specialized functions don't map cleanly into the language we were already describing human behavior with.

You're saying we only use certain parts of our brain for certain things, and the author is saying (with citations) that multiple regions of the brain are involved in most brain tasks. To me, this makes sense when you read about people who got brain surgery or whatever and then their brain re-wired itself, etc. Clearly there is a disagreement here. Can you point to this huge body of evidence that disagrees with the author?

I think the point is that it isn't a "myth" so much as an extremely simplified model that can still be very informative and useful.

> If you take out the engine - it doesn't run

And there are parts of the brain that you can reliably take out and damage specific things like speech/language or facial recognition.

Yes and no. The brain is complicated, and we have a lot left to understand about it.

https://www.webmd.com/brain/news/20191119/they-had-half-thei...

Those hemispherectomies were done on children.

Strokes or head traumas can produce very specific loss of abilities in adults.

I am not quite sure why this is being "debunked" now. Perhaps in part as status jockeying, i.e. "I'm ahead of the curve and not stuck with knowledge that was en vogue 10 years ago and all the Discovery-watching plebs has internalized" and in part a strange new dualistic movement that seeks to mystify the brain for some reason, perhaps in service of blank slatism.

I think the key here is that some tasks are very clearly localized, such as speech in Broca and Wernicke.

But others are not as localized. And functional areas might even move during phases of plasticity (i.e. being born blind).

So it seems very clear that some functionally distinct regions exist, but researchers still struggle to pinpoint very abstract things like memory, personality, and complex behavior.

Can we be sure what "localised" means in this context?

If you destroy an area and some people lose one particular function, while other people only lose small fragments of the function - which seems to be true of Broca's region - can the function really be said to be localised?

That's a good question, I'd need to ask a neurologist friend of mine.

IIRC there are some areas that are localized almost in the sense of a circuit.

Hearing is an example, which needs to process sensory information much faster (and more direct) than ordinary pathways would, in order to be able to construct spatial representation from latency differences.

I suppose "more direct" can be interpreted differently, but to the best of my knowledge the signal from your cochlea takes more axonal jumps[0] than e.g. visual, which jumps "only" through LGM[1]. Even more direct is the olfactory pathway which skips the thalamus altogether[2].

However, in the context of the article you might be referring only to intertelencephalic processing, in which case I'd love to read a paper which compares the directness of hearing vs other modalities.

[0]: https://teachmeanatomy.info/neuroanatomy/pathways/auditory-p...

[1]: https://www.ophthalmologyreview.org/articles/the-afferent-vi...

[2]: https://www.frontiersin.org/articles/10.3389/fncir.2015.0004...

Hi @porkbrain, it's going to take a few days but I'll ask and come back with such an article if my friend (whose specialty is auditory processing and sensor fusion) can recommend one.

And even if Broca's region is necessary for speech, that does not mean it is sufficient. You wouldn't assume an electronic circuit is localized to one resistor just because it breaks when that resistor is removed.

Suffered some minor strokes. Right left brain stuff was interesting. Lost ability to hand write. But could draw fine. Right side of body became very weak and numb. Some mental stuff was fine. Others were not. Last I looked up it seemed to match left and right brain theory. Creative vs math side, etc.

Fascinating. How is your ability to do math problems? Can you do them on paper at least?

All math or programming tasks become oddly hard. Something simple that I had done 1000 times before in seconds became a week long project.

After I had been on blood thinners for a bit and my mind recovers I sat down at a problem that I couldn’t figure out for six months. 10 minutes later it was done.

Had an ER visit were I was getting all questions wrong. Year, president, etc. I knew my answers were wrong. But I didn’t know why, or what they should be.

You've probably already heard of Dr. Jill Bolte Taylor, but if you haven't, you should look up "My Stroke of Insight". The TED talk version is quick and interesting -- she talks about exactly this. I'm working through her "Whole Brain Living" book and it addresses many of the exact points in this Nautilus article, although I can't resoundingly recommend the book as it has its own flaws.

I mean, cases like yours are one of the ways we learn about brain function.

Historically it was more about people who had some part of their brain removed or otherwise grossly damaged, but the principle is the same: when people lose part of their brain, how does their mind change? What can they still do, what can they not?

What do you think of the part where they say that when you measure whole brain activity you'll see that most tasks actually involve all of the brain? That's not really how q car works at all, some parts can have a primary and alternate effects, but not everything in the car will always be part of each process.

Also, I might misread, but it seems to see neurons are not different in different parts, so it seems that you could interchange the functionality and the pathways might not be due to specialization, but more to topology and arrangement of interconnections and proximity to things.

> But we have a huge body of evidence showing that there is a big difference in how the left vs. right brain processes information

I don't think we actually do have this evidence. In fact, I think there's been specific research that has debunked that idea.

Could it be that there is almost no distinction between brain parts but that the way a fetus grows 'specializes' certain parts?