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

When I go many days in a row without enough sleep, I find that my cognitive abilities (i.e. what I am capable of doing) does not seem to significantly decline--as judged by things I build and people I interact with.

But, my endurance of focus (the amount of time for which I can perform at a high level) does suffer.

The weird thing is that it doesn't feel like I can't keep going... it's just that I sort of somehow don't keep going. I find my mind wandering more easily, checking in on social media more, and then time passing more quickly when I do. I'm more likely to look up from Twitter or HN and be surprised at the time.

In short I don't seem to be any dumber while doing something, but number of things I get done in a typical time periods declines.

As I have come to understand this impact, it has given me greater empathy for addicts. My brain doesn't feel like a tired muscle, or like I'm doing anything wrong in the moment. It's only later, when I look back, that I realize I was making bad decisions and losing time. It has just reinforced how hard it is to use decision-making to recover from a situation where the brain has already been compromised by bad decisions.

Was his assessment basically just playing video games? I've noticed that's an activity I can do proficiently for an extended duration on very little sleep (along with things like "bulk" coding) but there are others I'm awful at unless I'm well rested (eg. complex planning, creative efforts like songwriting) and I've found my communication skills start to become impaired when I'm really sleep deprived.

I'd be curious to see how he performs on a broader spectrum of cognitive and even physical assessments.

An educational and insightful book, but it had me losing sleep because I got so anxious on needing more sleep. Talk about irony!

there have been complaints by serious people about the work in this book, see

https://statmodeling.stat.columbia.edu/2019/12/27/why-we-sle...

now, it's obvious to me that if I don't get 8 hours of sleep a night, my brain stops functioning properly and my entire life goes to shit very quickly. So I was happy to see a very popular book advocating sleeping well, and hopeful that if lots of people read it, they might have more respect for other people's sleep schedules.

The critic, Alexey Guzey, seems to be a guy who needs less sleep than I do, and also a guy who is into life-hacking/self-improvement type stuff. There's definitely a type of person who thinks "sleep is for the weak". I think he probably does have a bias towards sleeping less.

But I think the problems he points out about the book are pretty serious.

In particular, it seems that claims around sleep and longevity and other health outcomes (e.g. injury rates, cancer) are often unreliable or based on misinterpreted studies, and one case involves eliding data that contradicts the result.

Now, having myself experienced chronic sleep deprivation, and dealt with people who think they don't need to sleep but definitely do, I think the basic argument of the book is probably correct. But as the last line of that post quotes, "Good ideas do not need a lot of lies told about them to gain public acceptance".

What type of video games? That matters a lot to me. I can play a turn-based game like Civilization completely fine on little sleep (measuring the quality of play objectively, like by productivity or victory within a certain number of turns.) Soft real-time games like say a Mario platformer are a little worse but playable if I'm tired. Hard real-time games with very tight and sensitive timing like Guitar Hero or high-level Tetris are unplayable at anywhere near peak form if I'm not fully rested.