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Sleeplessness Impairs Memory
Anne Marie writes: "According to a new study on the interaction between memory and lack of sleep has yielded tantalizing results: not only is sleep necessary for the chemistry of laying down memories, but periods of extra sleep cannot "make up" for lost sleep. The implications for the IT industry where sleeplessness is a constant reality of employment are manifest." By morning, I will probably have no idea I ever posted this.
When I was entering college (1993), my father advised me to keep up with my daily sleep, since "you can't regain the sleep that you lose." His college education was in biology and human physiology, back in the late 1960's, so the information is potentially that old. I suspect that medical researcher's have known something about this phenomenon for years, and that this is just a continution or follow up study.
Hopefully though, people, especially academia and the technology fields will start taking this seriously, and try to accomodate the fact that we need adequate sleep (and a little recreation) to function at optimum levels of congnition and mental efficiency.
To email me,subtract my nick from my email address, starting with the second character. (hint: adto.uiuc.edu is wrong)
I read about "daily cycles" of sleep, and being someone who habitually feels crap in the morning, decided to try it. I found it seems to work.
Basically, the body goes into a sleep mode about 10pm. This mode lasts until about 2am. During this period, the body is most relaxed and quiet. After it starts waking up, sleep is more shallow.
I've usually liked staying up late to do mental stuff/work, because I'd feel more focussed and relaxed, esp. around 1am, but would feel awful in the morning. I see now that the 'late-night-focus' was because my body was in 'deep-relaxation' mode, ie. the time when it was most adapted for deep-sleep. By morning, I'd not only missed the deepest relaxation sleep period, but would still be in bed when the body was passing from light-awake (2am-6am) to medium-awake (6am to 10am). So I'd be trying to wake up at 7 -- a few hours after my body's most sharply-awake period had already passed.
I've started experimented with going to bed at 10, and found I wake up naturally and very refreshed and clear at 4.30-5am (much more refreshed than I do at 6.30).
So instead of cramming a few late night work hours, there's the alternative of taking an early night and working from 5-7am, straight after having had the deepest sleep possible.
Anyway, I must sound really "sad" advocating 10pm bed time... and for many it's just not possible, but for those who are interested, see Chopra.
PS. I once stayed up 56 hours for work... at least I think it was work... can I remember?
I had a buddy who decided that rather than getting some boring work study job in the library, it'd be easier to sign up in a long term research study in the food and nutrition department.
They wanted complete control over his input and output, so they gave him a gym bag with thermoses full of a special liquid nutritional concentrate which for the year became his sole source of sustenance. He also had latrine containers into which he had to put all his piss and shit. We'd all go out for Chinese and he'd be slurping his nutritional goo.
Every two weeks he'd go to the lab and get to eat something different -- two pounds of American cheese. There was a catch to this treat -- it was radioactive.
Post may contain irony: discontinue use if experiencing mood swings, nausea or elevated blood pressure.
Let me compliment you on a unusually good post.
I personally don't have access to my sources, since I've been out of school now for over fifteen years, but back then I did some literature research into this very subject too.
I remember a study which is very suggestive, which probably you could find if you have access to a good library. The study purported to show that the length of time between an event and the next REM cycle affected your ability to recall it accurately. If you were sleep deprived, you would remember things that occurred just before you got to sleep pretty much as well as you would during a normal cycle. Things that happened a long time before you got to sleep would not be recalled well or at all. Thus if you (like I used to when I was young) work for thirty or forty hours straight, you would remember the last shift pretty much as well as a normal shift, but the first shift would be recalled poorly. This pretty much also fits with my personal experience.
Another way to look at this is that time to REM sleep is the limiting factor in long term recall.
This would jibe pretty well with the study of medical residents. Medical residents who worked long shifts would learn pretty much the same as those that worked short shifts, just that most of the learning that occurred would be from the end of the shift. The beginning of the shift is for the benefit of the hospital, not the resident.
Post may contain irony: discontinue use if experiencing mood swings, nausea or elevated blood pressure.
If you read the article, the research was on procedural memory (such as learning a new juggling pattern, or getting better at Tetris), and had nothing to do with declarative memory (such as remembering what the capital of Algeria is), or episodic memory (such as remembering that you already posted a particular Slashdot story 2 weeks ago). I see from most of the comments that people are implicitly assuming that we're talking about declarative memory. So you can go on sleep-depriving yourselves without worrying about forgetting important facts (as far as this particular research is concerned).
The sleep pattern I use that works quite well(for about a month) is 3-4 hours at night, but then 3-4 15 minute power naps(fmpns) during the day. At the end of a semester on when I'm working on a big project I'll start using this sleep pattern. It takes me a day or 3 to adjust but afterwords I'm going pretty much non stop for 20 hours a day. Just have to make sure to schedule the naps. If you miss one it KILLS you.
About to catch 4 hours right now.
Humans are slow, innaccurate, and brilliant; computers are fast, acurrate, and dumb; together they are unbeatable
What I see you doing is denying a result you don't like.
Remember, you don't run an experiment which changes multiple variables. Otherwise, tracking down the cause of a variance is nearly impossible without a huge sample size (sufficient to analyse on any one variable at a time). Looking at varying "time frames... working scenarios [and] rhythms" would have made drawing a conclusion nearly impossible. Each of these factors may be isolated later -- but the point of the study, that some kinds of learning don't occur without sleep shortly after the experience is gained, is most certainly made.
I don't know what you do. Maybe your job is so rote you can afford to not learn anything for 4 days out of five. I, on the other hand, cannot. And that's what this study was about.
(Huh? You thought it was just that you can't make up sleep? Maybe you should read the articles before you post!)
I did a research project on sleep deprivation (titled "The effects of sleep deprivation on academic performance", and no, I wasn't the test subject), so I know a bit about the field.
First of all, there are many different opinions, and little, if any, consensus about even basic things. Experts disagree about many things, and I've seen studies that completely contradicted the findings of this one.
Here are some highlights of my research
A study of surgical house staff and medical students found no effect of cumulative partial sleep deprivation on learning and long-term recall.
Browne, B. J., T. Van Susteren, D. R. Onsager, D. Simpson, B. Salaymeh, and R. E. Condon. "Influence of sleep deprivation on learning among surgical house staff and medical students." Surgery 115.5 (1994): 604-610).
A meta-analysis of 19 other studies found that partial sleep deprivation (less than 5 hours in a night) is actually worse than total sleep deprivation.
Pilcher, J. J., and A. I. Huffcutt. "Effects of sleep deprivation on performance: a meta-analysis." Sleep 19.4 (1996): 318-326.
There is a relationship between sleep quality and mood.
Pilcher, J. J., D. R. Ginter, and B. Sadowsky. "Sleep quality versus sleep quantity: relationships between sleep and measures of health, well-being and sleepiness in college students." Journal of Psychosomatic Research 42.6 (1997): 583-596.
The effects of sleep deprivation are cumulative, but can be reversed by two nights of "recovery" sleep (10 hours a night).
Dinges, D.F., F. Pack, K. Williams, K. A. Gillen, J. W. Powell, G. E. Ott, C. Aptowicz, and A. I. Pack. "Cumulative sleepiness, mood disturbance, and psychomotor vigilance performance decrements during a week of sleep restricted to 4-5 hours per night." Sleep 20.4 (April 1997): 267-277.
There, I've refuted the main claims of the new study, namely that sleep deprivation affects memory, that you can't make up for sleep deprivation by sleeping more on following days, and that a little sleep is better than none. Unlike most Slashdot posts, I've even included my sources.
Here's the lesson for the day, as master Yoda might say it:
One study does not a fact make.
Also, note that bit about partial sleep deprivation being worse than total sleep deprivation--that came from a meta-analysis of 19 studies, and was a very strong correlation. Perhaps pulling the occasional all-nighter is better than staying up a few hours late every night...
anyone else amused that this story was posted at 2 in the morning?
I am.
Chuckling off to bed.
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