5 ms·

Now, I'm certainly not an expert on sleep, but my current night reading just happens to be "The Promise of Sleep" by Willam Dement, founder of the Stanford slee

by lutorm 17y ago

Now, I'm certainly not an expert on sleep, but my current night reading just happens to be "The Promise of Sleep" by Willam Dement, founder of the Stanford sleep center and student of Kleitman, the discoverer of REM sleep. And this article contradicts what he writes in so many ways. Here's what I took away from the book: Just as a start, the author got that thing about REM sleep being the only sleep that matters exactly backwards. Depriving people of REM sleep has not shown any effects on increasing sleep debt (ie feeling tired), it's the non-REM sleep that you need to not feel tired. (Which makes sense because in REM sleep your brain is essentially awake.) What the purpose of REM sleep is, is not known. Furthermore, the idea that you can "train" yourself to need less sleep has no basis in science. This does not mean there aren't a few people who have all kinds of strange sleep issues, but for the majority of people there seems to be no scientific evidence that this works at all. About the "intrinsic 28-hour pattern", in most cases (not all, there are probably people with real physiological disorders) this tendency to have a longer day than 24 hours is induced by artificial light in the evening. Electric lighting, and certainly staring into a bright LCD screen, is bright enough to register as daylight to your biological clock, and cause it to shift forward. In studies where people were isolated from artificial lights, people who normally would have a rhythm slightly longer reverted back to almost exactly 24 hours. Rather than "hacking your brain", it would probably be more beneficial for the majority of people to just learn about how sleep works and of the importance of managing it properly.

erlanger 17y ago
That explains why I slept so well when I was locked up (back as a young'n in juvie): You didn't have control of the light in your cell, so from ~10pm to ~7am lights were out whether you liked it or not. I'm a life-long insomniac.
- jongraehl 17y ago
  The reverse - going to sleep as the sun creeps up - is difficult for me. It feels worse to me to try to sleep as dawn comes than just an hour earlier. I'd expect to fall quickly and pleasantly asleep after an all-nighter, but the combination of dawn, the pounding of my heart and racing of my mind actually leave me awake and thinking for an extra few minutes. It's possible that going to sleep in that state gives me extra insight on what I was working on, but it doesn't feel good.
  - scott_s 17y ago
    Light is an indicator to our body to wake up. If you pull an all-nighter and want to go to sleep, avoid the sunlight as much as possible. Conversely, I like to sleep with the shades open, because I feel it's easier to wake up in the morning if there's natural light in my room.
  - lutorm 17y ago
    Interestingly, the effect of light on the biological clock reverses in the middle of the night, so that light in the early morning tends to make the cycle shorter. Which I guess also makes sense since that's how it would have to work with jetlag.
dcurtis 17y ago
I am trying to find a couple primary sources to back up your suggestion that I got the REM/other phases backwards. That would be quite embarrassing, but I am pretty sure I am correct. Does anyone know of any of any good studies done on REM deficit? Polyphasic sleep does not train the body to "need less sleep" directly. But it appears the body adapts to use the naps more efficiently than it would use a longer chunk of sleep. To suggest there is "no basis in science" for this seems kind of a stretch. There is science that describes this process. I'm aware that people claiming to have messed up biological clocks tend to have environmental or physiological factors that cause the problems. I have done pretty much everything sort of isolating myself from artificial light for a period of time longer than about a week, and my body is stuck on a 28-hour clock. Also, you suggest that people deprived of artificial light snap into a "exactly" 24-hour schedule. This is actually not correct. Many studies have been done showing that the default schedule ends up being about 25 hours when you deprive people of clocks and light sources.
- lutorm 17y ago
  Dement's book does not have any real references, but on p 257 he discusses a study by Tom Roth and Tim Roehrs where paired subjects were awakened when one of them entered REM sleep. The pairs thus had identical sleep disturbances and were different only in whether they were woken up in REM sleep or not. He says "The results were striking. The daytime sleep tendency did not change in the REM sleep-deprived group ... whereas the yoked control group (which lost much more non-REM sleep) became significantly sleepier in the daytime." To be fair, he then goes on with some cautionary notes about the small numbers of the study and how some older studies had not found a difference. There was no mention of studies finding the opposite, though.
  - dcurtis 17y ago
    Yeah, there appears to be very little hard research on the subject, but my personal experience from reading neuroscience journals has led me to the understanding that REM sleep removes tiredness. In fact, people with REM sleep behavior disorder -- that is, people who naturally do not go into REM sleep normally, and when they do, they have odd physical behaviors -- complain of chronic tiredness and sometimes end up with serious mental disorders. The other phases of sleep are even less understood than REM, so I am going to trust my instinct and go with the real research that has been published on polyphasic sleep.
10ren 17y ago
I was thinking of that study of a guy who lived without clocks for several weeks (I think it was underground), and he tended to a 25-hour pattern (IIRC). But of course (apart from the sample size), he had electric lighting.
- deleted 17y ago
  [deleted]
tc 17y ago
there seems to be no scientific evidence that this works at all Do you know if there has been a serious scientific study of this technique? Otherwise, you're being a bit disingenuous in subtly applying the "unscientific" label. The set of things that are true is much larger than the set of true things that have been proven scientifically.
- lutorm 17y ago
  Like I said, I'm just restating what I read in Dement's book, which hasn't talked about this technique at all except to say that people who wake up frequently (like people with sleep apnea) are much more tired than they should be, because the awakenings actually don't change the total amount of sleep that much. So there seems to be evidence indicating that many short chunks of sleep are less effective at reducing sleep debt than one chunk of the same total length. It's as if there's a "startup cost" to falling asleep, and it doesn't start to benefit you until after some time has passed. So I should have formulated myself more carefully by saying: Studies indicate that short periods of sleep is less effective than long ones, and that each individual requires a certain amount of sleep per night (but which varies with individual and then as you age). He did go so far as to say something about how he thought methods advocating that you can train yourself to sleep less are "dangerous", given how much sleep deprivation affects your health and ability to do things like drive or operate other machinery safely.
a-priori 17y ago
What I worry about is recent studies that suggest that declarative memories (memories of events, objects, and so on) are consolidated during slow-wave sleep. I'm thinking specifically of Rasch et al., 2007 (DOI: 10.1126/science.1138581). Since the theory behind these polyphasic schedules is that it mainly reduces the time spent in slow-wave sleep, I would expect that the declarative memory would be affected.
- fcr 17y ago
  This study http://www.oniros.fr/A1350.pdf http://www.oniros.fr/A1350.pdf seems to indicate that sleep duration has no effect. Their interpretation is that a process is triggerd when you enter sleep but once triggered it is independent of wheter you sleep or not.
crocowhile 17y ago
You are definetely right but let me just comment about the physiological exception. In the in the case of this blog post the might actually be some differences. The writer may really have some genetic problem in his/her circadian clock. Sleep is known to be under regulation of two mechanism: a circadian mechanism (about 24 hour for most of us) and a homeostatic mechanism. It is known (it is actually one of the few things we actually know pretty well about sleep) that the NREM is under control of the homeostatic mechanism while REM is under control of the circadian mechanism. The blog author has a longer cycle and it is likely that his/her REM kicks in later on in their night, therefore being incompatible with obtaining enough REM. By doing polyphasic he/she might be able to compensate for that.

by lutorm 17y ago

erlanger 17y ago

That explains why I slept so well when I was locked up (back as a young'n in juvie): You didn't have control of the light in your cell, so from ~10pm to ~7am lights were out whether you liked it or not. I'm a life-long insomniac.

jongraehl 17y ago
The reverse - going to sleep as the sun creeps up - is difficult for me. It feels worse to me to try to sleep as dawn comes than just an hour earlier. I'd expect to fall quickly and pleasantly asleep after an all-nighter, but the combination of dawn, the pounding of my heart and racing of my mind actually leave me awake and thinking for an extra few minutes. It's possible that going to sleep in that state gives me extra insight on what I was working on, but it doesn't feel good.
- scott_s 17y ago
  Light is an indicator to our body to wake up. If you pull an all-nighter and want to go to sleep, avoid the sunlight as much as possible. Conversely, I like to sleep with the shades open, because I feel it's easier to wake up in the morning if there's natural light in my room.
- lutorm 17y ago
  Interestingly, the effect of light on the biological clock reverses in the middle of the night, so that light in the early morning tends to make the cycle shorter. Which I guess also makes sense since that's how it would have to work with jetlag.

dcurtis 17y ago

I am trying to find a couple primary sources to back up your suggestion that I got the REM/other phases backwards. That would be quite embarrassing, but I am pretty sure I am correct. Does anyone know of any of any good studies done on REM deficit? Polyphasic sleep does not train the body to "need less sleep" directly. But it appears the body adapts to use the naps more efficiently than it would use a longer chunk of sleep. To suggest there is "no basis in science" for this seems kind of a stretch. There is science that describes this process. I'm aware that people claiming to have messed up biological clocks tend to have environmental or physiological factors that cause the problems. I have done pretty much everything sort of isolating myself from artificial light for a period of time longer than about a week, and my body is stuck on a 28-hour clock. Also, you suggest that people deprived of artificial light snap into a "exactly" 24-hour schedule. This is actually not correct. Many studies have been done showing that the default schedule ends up being about 25 hours when you deprive people of clocks and light sources.

lutorm 17y ago
Dement's book does not have any real references, but on p 257 he discusses a study by Tom Roth and Tim Roehrs where paired subjects were awakened when one of them entered REM sleep. The pairs thus had identical sleep disturbances and were different only in whether they were woken up in REM sleep or not. He says "The results were striking. The daytime sleep tendency did not change in the REM sleep-deprived group ... whereas the yoked control group (which lost much more non-REM sleep) became significantly sleepier in the daytime." To be fair, he then goes on with some cautionary notes about the small numbers of the study and how some older studies had not found a difference. There was no mention of studies finding the opposite, though.
- dcurtis 17y ago
  Yeah, there appears to be very little hard research on the subject, but my personal experience from reading neuroscience journals has led me to the understanding that REM sleep removes tiredness. In fact, people with REM sleep behavior disorder -- that is, people who naturally do not go into REM sleep normally, and when they do, they have odd physical behaviors -- complain of chronic tiredness and sometimes end up with serious mental disorders. The other phases of sleep are even less understood than REM, so I am going to trust my instinct and go with the real research that has been published on polyphasic sleep.

10ren 17y ago

I was thinking of that study of a guy who lived without clocks for several weeks (I think it was underground), and he tended to a 25-hour pattern (IIRC). But of course (apart from the sample size), he had electric lighting.

deleted 17y ago
[deleted]

tc 17y ago

there seems to be no scientific evidence that this works at all Do you know if there has been a serious scientific study of this technique? Otherwise, you're being a bit disingenuous in subtly applying the "unscientific" label. The set of things that are true is much larger than the set of true things that have been proven scientifically.

lutorm 17y ago
Like I said, I'm just restating what I read in Dement's book, which hasn't talked about this technique at all except to say that people who wake up frequently (like people with sleep apnea) are much more tired than they should be, because the awakenings actually don't change the total amount of sleep that much. So there seems to be evidence indicating that many short chunks of sleep are less effective at reducing sleep debt than one chunk of the same total length. It's as if there's a "startup cost" to falling asleep, and it doesn't start to benefit you until after some time has passed. So I should have formulated myself more carefully by saying: Studies indicate that short periods of sleep is less effective than long ones, and that each individual requires a certain amount of sleep per night (but which varies with individual and then as you age). He did go so far as to say something about how he thought methods advocating that you can train yourself to sleep less are "dangerous", given how much sleep deprivation affects your health and ability to do things like drive or operate other machinery safely.

a-priori 17y ago

What I worry about is recent studies that suggest that declarative memories (memories of events, objects, and so on) are consolidated during slow-wave sleep. I'm thinking specifically of Rasch et al., 2007 (DOI: 10.1126/science.1138581). Since the theory behind these polyphasic schedules is that it mainly reduces the time spent in slow-wave sleep, I would expect that the declarative memory would be affected.

fcr 17y ago
This study http://www.oniros.fr/A1350.pdf http://www.oniros.fr/A1350.pdf seems to indicate that sleep duration has no effect. Their interpretation is that a process is triggerd when you enter sleep but once triggered it is independent of wheter you sleep or not.

crocowhile 17y ago

You are definetely right but let me just comment about the physiological exception. In the in the case of this blog post the might actually be some differences. The writer may really have some genetic problem in his/her circadian clock. Sleep is known to be under regulation of two mechanism: a circadian mechanism (about 24 hour for most of us) and a homeostatic mechanism. It is known (it is actually one of the few things we actually know pretty well about sleep) that the NREM is under control of the homeostatic mechanism while REM is under control of the circadian mechanism. The blog author has a longer cycle and it is likely that his/her REM kicks in later on in their night, therefore being incompatible with obtaining enough REM. By doing polyphasic he/she might be able to compensate for that.