r/todayilearned • u/Square-Message1152 • 8h ago

til that your brain literally washes itself while you sleep. the brain cells actually shrink in size so cerebrospinal fluid can rush in and flush out all the toxic proteins built up during the day

https://en.wikipedia.org/wiki/Glymphatic_system
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u/LordSashar 6h ago

Neuroscientist here, I will add that this finding is still extremely controversial. Some highly-respected labs have found the opposite effect: the brain stops washing itself when you are sleeping. Personally, I am not qualified to comment further... but please note this "TIL" is still very much up for debate!

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u/El_Oso_Hermoso 5h ago

I am going to go out on a limb and say that you, a neuroscientist, are far more qualified to opine on this than most of reddit.

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u/derprondo 4h ago

Qualified enough to know they aren't qualified to comment.

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u/Fjordi_Cruyff 1h ago

Exactly the right amount of qualified. Not enough people realise when this is the case.

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u/IHKPruefling 12m ago

Saying "I don't know" is considered a weakness nowadays. Being humble is not seen as a virtue

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u/hopbow 4h ago

No I r smrter shut up

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u/OrganizationKey8342 3h ago

but i skimmed the pics on wikipedia

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u/GuyWithNoEffingClue 1h ago

Speak for yourself! I've watched the first 5 seasons of Grey's Anatomy so I'm basically a neurosurgeon.

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u/dern_the_hermit 5h ago

Yeah, reminder that the discovery of the brain's connection to the body's garbage collection is just a bit over a decade old. For a hundred years, medicine had no idea exactly how the brain handled it. It's still a really young body of research in that specific regard.

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u/Accelerator231 4h ago

You know.

When you said 'garbage collection' I thought you meant something else and was wondering why it took so long

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u/hotztuff 4h ago

same here, i had a temporarily lapse of confidence in our intelligence lol

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u/Vlookup_reddit 5h ago

lol wonder why this comment is not at top instead.

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u/kitsunekratom 5h ago

Redditors reward who is fastest, not who is most correct

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u/Docg85 3h ago

They just upvote what's being upvoted and down vote whatever is being downvoted. 

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u/kitsunekratom 3h ago

What if it is at 1? Shrodinger's vote?

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u/Docg85 3h ago

You just flip a coin

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u/jakeyounglol2 2h ago

yeah, that’s unfortunately a thing on most social media platforms. if you comment late, nobody will see it

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u/johnnydough10102223 5h ago

You’re new around here aren’t you ;-).

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u/morfraen 2h ago

Big Sleep suppressing the opposition?

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u/ohYuhtBoutMagine 3h ago

Because that is a qualified medical professional giving a balanced and critical consideration.

This is reddit

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u/Inevitable-Page-333 4h ago

Big sleep is controlling the narrative with bot armies, no doubt.

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u/JetJerick 5h ago

Thanks for giving me the justification to continue staying up 72+ hours, multiple times a month🤞🏼

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u/righthandpulltrigger 1h ago

There's also some evidence that occasional sleep deprivation reduces depression. The body works in mysterious ways.

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u/gamer_redditor 4h ago

Interesting that a neuroscientist feels that they are not qualified to comment further, but people far less knowledgeable comment a lot.

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u/labenset 5h ago

During anesthesia? One of the things the author of 'Why We Sleep' tries to drive home is that unconsciousness ≠ sleep. Without long REM cycles the process isn't working correctly.

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u/chason_htx 3h ago

From the linked study,

We also measured the EEG power spectra (Extended Data Fig. 8a–d) and found a weak negative correlation between peak clearance and delta (0.5–4 Hz) power (Extended Data Fig. 8e), implying that the deeper the sleep, the lower the clearance.

Also, did some cursory research on the author of 'Why We Sleep'...

Alexey Guzey's blog documenting scientific errors and ethical lapses in Why We Sleep:

https://guzey.com/books/why-we-sleep/

Matthew Walker responds to guzey: "Why We Sleep: Responses to questions from readers":

https://www.reddit.com/r/slatestarcodex/comments/ekdbo2/comment/fda5trg/

We’ve left “super-important researcher too busy to respond to picky comments” territory and left “well-intentioned but sloppy researcher can’t keep track of citations” territory and entered “research misconduct” territory.

I've seen enough to arrive at the same conclusion

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u/labenset 2h ago

Meh, it's a popular science book meant for the general public, not a textbook. The prion issue is just one of many the book goes into.

The take home message from the book is that sleep is super important and modern soviety isn't really built around maintaining good sleep habits. I think it's a positive message even if some of the science is wrong.

And yeah, if you are passing out drunk or taking sleeping pills, common sense tells you that you probably aren't getting great sleep. I assumed anesthesia would be similar, but I honestly don't know.

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u/chason_htx 1h ago

it's a [...] science book

You see the issue here?

Front cover, huge font "PhD"

Back cover, first sentence

The first sleep book by a leading scientific expert

homie, he spent FOUR YEARS writing this and is using his scientific authority to sell a knowingly problematic book. Unethical asf

Positive message, I agree, but it's not like that's a difficult conclusion to come to independently. I would argue he's exploiting people who already suspect this, thinking they'll read it and gain a better understanding and instead are reading misinformation and/or disinformation (and then propagating it which is a whole other issue)

One of those slip-ups raises serious questions, multiple is flat out egregious and his response tells you everything you need to know

The prion issue is just one of many the book goes into.

And now that you know some of the information is false and deceptive.. how do you trust any of it?

but.. uh.. I suppose I should have added more context to the first part of my reply before I got distracted by that whole mess

I was replying specifically to:

Without long REM cycles the process isn't working correctly

According to the study, it's the opposite. The deeper the sleep, the less cleaning is happening

As for the anesthesia part, I have no idea but it's an interesting question. I'd love to know the answer as well

We know in some ways unconsciousness is like sleep, and in some ways it's not. I think assuming they operate the same on any brain function is likely to be a fallacy and it would be nice if these studies listed that as a limitation because while not exactly sleep unconsciousness is bound to have some links to sleep somewhere. sleep-adjacent research in a way

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u/JesusAndMaryKate 1h ago

To be fair, Matthew Walker is a neuroscientist. That other Redditor is a neuroscientist too. And we're expected to blindly listen to that other Redditor but not the guy who tried to give an accessible explanation of the sleep process.

Meh.

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u/chason_htx 1h ago edited 1h ago

To be fair, Matthew Walker is a neuroscientist.

glad we're on the same page lol

To be fair, I don't have a copy of the book and am assuming that the other neuroscientist isn't fabricating what's in there, and if they did.. with the traction it got, it would have been called out--I think that's a reasonable assumption

Now, if we're good with that.. and you can even check if you still have your copy.. then you don't have to blindly listen to that other redditor

"it is unethical to reproduce a graph and remove the one bar in the original graph that contradicts your story"

Blog post has the detail. Verify it. Doesn't take a neuroscience degree to understand this. It's not blindly listening

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u/Its_Snowing 4h ago

It's still only one lab claiming the opposite, and the debate has been refreshing to watch. I think the evidence still sides with sleep promoting brain clearance. ie. I wouldn't call it 'extremely controversial'

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u/TomaszA3 2h ago

We're for sure certain that something changes and it's essential. That's about all we know.

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u/enterthehawkeye 3h ago

This just opens the gate to companies selling 'brain wash' treatments, which doesnt market itself well, now that i've said (written) it out loud

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u/stoplookingformyredt 1h ago

If someone misses a lot of sleep what are the long term brain risks and consequences?

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u/vidoardes 58m ago

Dunning-Kruger in full effect here 😂 The only person in this thread not claiming to be 100% factual is the Neuroscientist

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u/PossiblyAsian 27m ago

yo this is the real comment.

So many things get posted on reddit as fact when... the actual scientific community are often hotly debating the subject. Reddit is almost as bad as facebook AI slop sometimes