Ability to learn is affected by the timing of sleep | Hacker News Reader

Ability to learn is affected by the timing of sleep

scientificamerican.com

152 pointsduaneb30 comments

Science Daily had article a few months ago on how sleep prunes the "noise" from the brain...

"Sleep researchers at the University of Wisconsin-Madison School of Medicine and Public Health believe it is more evidence for their theory of "synaptic homeostasis." This is the idea that synapses grow stronger when we're awake as we learn and adapt to an ever-changing the environment, that sleep refreshes the brain by bringing synapses back to a lower level of strength. This is important because larger synapses consume a lot of energy, occupy more space and require more supplies, including the proteins examined in this study."

"Sleep — by allowing synaptic downscaling — saves energy, space and material, and clears away unnecessary "noise" from the previous day, the researchers believe. The fresh brain is then ready to learn again in the morning"

http://www.sciencedaily.com/releases/2009/04/090402143455.ht...

a mechanism for occam's razor, where the parsimoniousness of theory complexity is motivated by conserving actual resources.

What is better now, learning in the morning or in the evening?

Nobody knows for sure is suppose, but i will think about it all day....

Does anybody has the same problem? When i read this stuff i will think about it every time i learn. I can't even drink coffee any more without thinking about the health implications i know about.

Received wisdom from my school system says that pupils are more attentive in their first three hours of the morning, then their attention drops as they run low on sugar; they are less focused in the afternoon.

Discounting the effect of metabolism (by comparing the afternoon period with the after dinner period, or even by comparing a normal day and one spent vaguely awake after an all-nighter), the Italian study's "spring-cleaning" thesis about low-level background activity rising during the day and lowering signal to noise for some mental processes rings true to me.

To my knowledge, this is pretty standard advice among students - review your notes before you sleep to help you remember them.

The explanation I've heard is that sleep is when long-term memories are formed; something put into short-term memory will have less time to erode if you sleep right afterwards.

I have heard a similar advice, but in the morning before class. Your brain has the most capacity in the morning, because over the day all the other information makes you exhausted and the amount you can learn on a single day is limited.

It is way easier to learn in the evening, that is what most students do anyway.

Okay, I have to ask this now: why is it then that I keep hearing from my friends at CMU and MIT that it's totally normal for them to go on 2 hour sleep/night? I hear this from professors too, "Oh, when I was your age I was working x many hours and getting by on not more than 3 hours of sleep a day!" By the way I'm someone who comfortably sleeps 8 hrs./day -- and in comparison to my friends I never received marks that were very impressive.

The examples in front of me (that I have known personally) who're doing so well -- or the science journals that say the opposite -- who do I believe?

Short answer -- your friends have 6 hours/night more study time than you. My bet is that if both of you studied the same amount of time but you got 8 hours and they 2, you would perform better, assuming your study habits are equally good.

What I've learned is that sleep IS important -- it's better to sleep than not to sleep. HOWEVER, staying up late and memorizing material over and over is definitely worth more than sleep is (for recall purposes). If you don't have time to review X due to sleep and X is on the exam, then you definitely lose out, right?

I have been an 8 hour/night sleeper. The attitude there is that I must get 8 hours of sleep, even at the expense of other things, such as making sure I obsessively know every single little fact in the material. 2 hour/night people care about memorizing every last detail of the material, at the expense of sleep.

I found I memorized best by memorizing 10-12 pages of notes so I could recite them from memory, recalling them all lying in bed, then recall them in the morning and touch up throughout the day. You just can't squeeze that in if you get 8 hours/sleep on an overloaded schedule!

There's also much more to learning, studying, and sleeping than the amount of time you spend.

Don't be afraid to discount some of those stories as bravado and self-aggrandizing reports. (see: the Four Yorkshiremen http://www.youtube.com/watch?v=Xe1a1wHxTyo )

That makes a lot of sense. I've often found myself dreaming about a problem I struggled with before going to bed, then magically "realizing" the solution immediately after waking up in the morning.

Memorizing arbitrary words for a study is a terrible proxy for meaningful learning.

That reminds me of the creativity studies that get promoted in the press these days, most prominently in Jonah Lehrer's new book. They all assume they know how to measure creativity!

David Deutsch criticizes this stuff in his recent book. You might like it.

http://beginningofinfinity.com/

Memorizing arbitrary words is a good proxy for learning new languages, where the hardest part is actually memorizing arbitrary words.

The trick to learning vocabulary would be to make these words meaningful and not arbitrary, for example by learning words related to an activity or a theme (which happens naturally when you spend time in a foreign country). Meaningless words are more reliably remembered by making up a story about them, even though that technically adds to the quantity of information to remember; if the subjects had been encouraged to use those strategies the gains might drown the before-sleep effect.

I recommend to read Brain Rules by John Medina. http://www.brainrules.net/.

He explains in really simple way how brain works and what is best for brain to keep evolving and getting smarter. One of the rules: Sleep well - think well

That's very interesting. I've been studying kanji in the morning because I'm a morning person, making it easier in the short run, but it looks like working on it in the evenings is actually better for long term retention.

For kanji, it works best to keep practising them several times every single day. Every 2-3 hours. You'll be able to learn a lot of them, much faster this way. You can use the open source software anki to plan which ones to review on a regular basis.

I'm already using Anki. As for the every 2-3 hours thing, it's hard to fit that into my schedule. There's an Android app called Ankidroid though that I haven't looked into. If it supports syncing with your desktop deck, I'll try to use that to fit in some practice every few hours.

Note---it does. I use it for command-line utilities.

Yes it does, and it's available through the open source appstore on Android (that I recommend as well).

My anecdotal experience has been that short naps between reading works brilliantly in terms of retaining the concepts. I always used to take a nap after reading for about 40min - 1hr in my college days.

I have had the same experiences. After a given amount of hard studying (anywhere from an hour to a few hours), I find that I cannot maintain focus anymore. A short nap always fixes the problem, and when I come back to it things usually stick much better.

The second comment made me think insight works as a side-effect of memory consolidation: transforming short-term memory to long-term involves linking it to existing memories. This may reveal two kinds of insights: 1, straightforward connections to prior knowledge (oh, this is like that); 2, by factoring out known commonalities from a new memory, connections within the new memory itself may become obvious.

I don't know if this is a cultural thing, but my parents have always told me, as a kid, to read my classnotes for a few minutes before sleeping. In my experience this works pretty well. Glad to see there is now some science to support it.

I wonder what happens during polyphasic sleep, where you sleep multiple times per day. Of course, the amount of sleep you get each time is far less (I'm trying a three-hour nap at night, then three twenty-minute naps throughout the day), but it's entirely REM sleep [1].

REM sleep is also when "memories are consolidated" [2], so multiple REM sleeps throughout the day should drastically improve one's information retention and therefore one's learning.

1. http://en.wikipedia.org/wiki/REM_rebound

2. http://en.wikipedia.org/wiki/Rapid_eye_movement_sleep#Memory...

Well, obviously there's not going to be any studies on such a nichey niche of a topic. There is a good way to measure memory performance, statistics kept by a spaced repetition flashcard system with a few hundred or thousands of flashcards, but the overlap between SRSers and polyphasicers seems low. The one example I know of, an Anki user on LessWrong, reported that his statistics were badly hurt during his polyphasic experiment.

If you believe that sleep's purpose is to weaken synapses/reset the brain, it's entirely possible going through less than three or four REM cycles before waking would be undesirable in that it may take more than one cycle to properly "wipe the slate clean". Granted, it's impossible to do much more than speculate at this point given the (relative) lack of research/knowledge on the topic so far.

I always figured it was because I had less other things to think about between me and the next morning. I could learn something and think about it a little while I was lying in bed trying to get to sleep VS trying to learn something and then shift to some other cognitive activities afterward.

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