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The effects on cognition of sleeping 4 hours per night for 12-14 days

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Re: The effects on cognition of sleeping 4 hours per night for 12-14 days

#151

Post by balfirevic »

jkhdigital wrote: post #123
oh-4-fucks-sake wrote: post #65

Earlier quoted context omitted.

I think that's what other recent psychological/neurological research has found too (citation needed--but do remember reading about it recently from multiple sources). It figures that everyone each has their individual baseline "propensity to stay focused"--and sleep deprivation degrades someone's focus below that. You take a normal person and sleep deprive them, and their "propensity to stay focused" is lowered, but…

> Ergo, ADHD might have a large sleep component. Yeah, I can count on one hand the number of times in my life when I woke up in the morning, even after a good night of sleep, and felt "refreshed". I didn't even know what that meant until I had a conversation with a coworker who just hops out of bed and is "on" immediately. Feels like there is a connection with my ADHD diagnosis.

Did you manage to improve it, feeling refreshed after waking up?

Re: The effects on cognition of sleeping 4 hours per night for 12-14 days

#152

Post by texascloud »

0xddd wrote: post #42
texascloud wrote: post #21

Earlier quoted context omitted.

I wouldn't say this is refuting even a minority of claims in the book. It appears to be a thorough fact check of a small percentage of claims, some of which is going after the author over wording and inconsistencies. It's fair criticism, but by no means invalidates a majority of the information regarding sleep that Walker presents

Except there are cases where Walker went so far as to remove portions of a graph to support his argument. This kind of manipulation shouldn't be allowed to stand and it's frustrating (though not surprising) to see a book that relies on this sort of dishonesty get so much uncritical attention and praise. I can't put it any better than Andrew Gelman: "If the data didn’t matter, then why did you include them in your dam…

Okay, he removed the 5 hour bar. I get what the author in your link is upset about, leaving out data points. But imo that's not good enough to make me throw out all the information in that book.

It sounds like the author is upset a book about getting enough sleep is getting so much attention. If they're upset at the way Walker misrepresents information, then I'd hate to see the author's blood pressure while feverishly researching the bias of every article they come across

Re: The effects on cognition of sleeping 4 hours per night for 12-14 days

#153

Post by kweinber »

conistonwater wrote: post #90
hawkice wrote: post #87

Earlier quoted context omitted.

This is by far the most important thing for HN to learn about this. The default level of self deception on this front is enormous.

I don't think it's quite the same as self-deception. The way I understood it is that it's more like alcohol: the first thing to go is your ability to judge for yourself whether your judgment is impaired.

It is fair to say that using your cognition to measure your own cognitive decline is unreliable ;-)

Re: The effects on cognition of sleeping 4 hours per night for 12-14 days

#154

Post by texascloud »

praptak wrote: post #27
piercebot wrote: post #20

Earlier quoted context omitted.

This refutation is authored by the same person who conducted the study to which these comments are attached :)

I did some digging and it is pretty solid to me. It's sad that Walker did not respond to this.

Proof of digging?

Re: The effects on cognition of sleeping 4 hours per night for 12-14 days

#155

Post by karpierz »

lolc wrote: post #78
karpierz wrote: post #28

It seems like the author tested rote activities that were well within their comfort zone; I'd be curious to see how well they'd perform when trying to learn something new or work at something that they hadn't practiced before.

Given that sleep deprivation is commonly assumed to lead to worsening reaction times, rote tasks should show an effect. It is interesting they didn't. Apart from that, I agree that there is more to sleep deprivation than reaction performance. For example, some of my most creative moments were in highly sleep-deprived states. But how am I supposed to measure that?

It's interesting, but it doesn't look like the reaction time windows are particularly tight. 500ms is a generous reaction time. And the FPS scenario didn't really test snap accuracy or reaction time, the limiting factor on completion time seems largely dependent on movement.

I think a more interesting metric of reaction time would be using a competitive FPS or fighting game, that require tight reaction times and decision making. That way, any change in reaction time will be reflected.

Re: The effects on cognition of sleeping 4 hours per night for 12-14 days

#156

Post by 29athrowaway »

Hours of sleep may not necessarily reflect how well rested a person is.

There are levels of sleep: NREM ("quiet sleep") and REM ("active sleep"). NREM has 3 stages: 1 (almost awake), 2 (light sleep), 3 (deep sleep).

The deeper your sleep, the most rested you will be. Some people require fewer hours of sleep because they spend more time in deep sleep.

Re: The effects on cognition of sleeping 4 hours per night for 12-14 days

#158

Post by texascloud »

biophysboy wrote: post #44

Guzey had another blog post on Matthew Walker's sleep book posted on HN a while back. I thought it was a bad faith critique, from my own biophysics perspective. We had some back and forth, guzey seemed nice & respectful enough, but I still had my misgivings about the critique. Sleep is very much an open question. HN seems to really love maximizing cognition and the overall efficiency of their life. That said, if you…

It's so strange to see "independent researchers" attempt to poke holes by any means in an argument meant to protect people from the ill effects of sleep deprivation, yet provide zero non-anecdotal evidence to support lack of sleep being beneficial.

Discounting Walker's argument with "he's not thorough" and then providing a "study" done by one person with no professional research experience appears fine for HN

Re: The effects on cognition of sleeping 4 hours per night for 12-14 days

#159

Post by texascloud »

retreatguru wrote: post #91

Is it just me, but how can this be taken seriously when the author was trying to show no result. While I love self experimentation, publishing it as if it’s valid science is unfortunate.

Agreed. It's dangerous. This is simply someone's personal experiment and their experiences written up. It's proof of nothing other than "I did something"

Re: The effects on cognition of sleeping 4 hours per night for 12-14 days

#160

Post by spacephysics »

kthxbye123 wrote: post #120
spacephysics wrote: post #56

Since a few years ago (when I read Why We Sleep [0]) I’ve made it my priority above all else to allow myself 8 hours of sleep, even if I don’t ‘use’ all of it. With more sleep, an innumerable amount of things are better (as read in the book), but subjectively I noticed the following after about a month straight of good sleep: * Pain was far more manageable (IBS, MMA injuries) * Sleep was more restorative when I woke…

>> or carnivore with a focus on ketosis Following a "carnivore" diet is a really terrible idea. Unless you're an Inuit living in the frozen north, you should eat some greens.

Going on 3 years now, with comprehensive blood tests taken every 3-4 months for 2 years. Never had better markers for inflammation (below error threshold), cardiac health, liver health, etc.

Tried keto (proper), vegan, vegetarian, low-FODMAP, paleo, all without success. Found a forum of other IBS people, and decided to risk going against mainstream 'authority' such as the American Heart Association.

So far, feel better than I ever have, on all markers I could measure objectively, and subjectively.

Whats a terrible idea is to have fats linked to heart disease in a massive lie that spanned decades, breed fruit for higher sugar, then say sugar from fruit is fine and healthy, but refined sugar should be moderated (even then its not discouraged). Or in the face of (currently anecdotal, I agree) evidence of dozens and dozens of chronic, autoimmune diseases cured by a carnivore diet from thousands of people. (Harvard Survey finished collecting data end of April)

Cured meaning we've removed the inflammatory foods causing the chronic illness. At least see it as an elimination diet, to where a user can add foods back in, and find out whats causing the adverse symptoms initially.

But science remains dogmatic, as history shows, for better or worse.

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