Polyphasic Entrainment, Part I
I am under the impression that one's body starts to get a certain amount of "sleep memory", which is similar to the so-called muscle memory.
I think that when we sleep on a regular schedule, it becomes easier and easier for us to sleep and wake up according to the schedule. For example, when I slept monophasically, it was much easier for me to awaken at 7:00 am, and to sleep at 11 pm because I consistently did just that. When I switched to a biphasic schedule (pre-blog) to spend time with my wife, my schedule shifted so that I expected a nap right after work, and then to sleep 1-6 am. As I continued this practice, it got easier and more refreshing.
For normal nighttime monophasic sleep, this entrainment is understandable. There are a large number of zeitgebers that indicate we should sleep, most strongly a day-night (read, "light-dark") cycle. The workings of most human societies reinforces this as well.
But what causes the entrainment to happen? According to these pages (thanks to "mc" for the latter link), our circadian rhythm is controlled largely by a handful of genes (and their protein expresssions).
Quoth the first (decidely more approachable for the layman) article:
There's a bit of jargon in there, too, but I think you can get the gist of what's going on with the production-inhibition-production cycle for the proteins.
So how does our body know when to time the clock? The SCN can be stimulated to modify the schedule because stimulation by light affects the shape (and thus effect) of proteins so that they inhibit production of the BMAL1 protein. Depending on timing, this could mean that you can shift your schedule forward or backward, but ultimately it's about 24 hours. I think that repeated exposure here also creates other cues internally to reinforce the behavioral patterns of mono- or bi-phasic sleep.
Obviously, there's more to this... sleep deprivation and other physiological and psychological factors can affect when we feel we need to sleep. Does the brain produce the light-modified protein in order to change the circadian rhythm? Does it inhibit production of the proteins, or create others that inhibit the inhibitors? I'll need to do more research.
But all of this applies to full-on circadian cycles and monophasic sleeping directly. It doesn't address ultraradian cycles, such as those encouraged by polyphasic sleeping.
Why am I asking this? I'll finish up in my next post on my observations of my personal polyphasic entrainment.
-sean
UPDATE - Sunday, Dec. 18th, 2005, 8:26 pm: Replaced the pasting from the article. I referenced the wrong part and didn't proofread enough... I was in a hurry. Thanks to mc for pointing it out.
I think that when we sleep on a regular schedule, it becomes easier and easier for us to sleep and wake up according to the schedule. For example, when I slept monophasically, it was much easier for me to awaken at 7:00 am, and to sleep at 11 pm because I consistently did just that. When I switched to a biphasic schedule (pre-blog) to spend time with my wife, my schedule shifted so that I expected a nap right after work, and then to sleep 1-6 am. As I continued this practice, it got easier and more refreshing.
For normal nighttime monophasic sleep, this entrainment is understandable. There are a large number of zeitgebers that indicate we should sleep, most strongly a day-night (read, "light-dark") cycle. The workings of most human societies reinforces this as well.
But what causes the entrainment to happen? According to these pages (thanks to "mc" for the latter link), our circadian rhythm is controlled largely by a handful of genes (and their protein expresssions).
Quoth the first (decidely more approachable for the layman) article:
- The transcription factors that turn on the light-induced promoters are dimers of the CLOCK protein and a protein designated BMAL1. These dimers turn on
- the Per gene;
- Cry, the gene encoding cryptochrome
- a gene whose product inhibits transcription of Bmal1
- effector genes (such as the gene encoding arginine vasopressin)
- The Per and Cry mRNAs are exported to the cytoplasm where they are translated.
- The PER and CRY proteins then form dimers that enter the nucleus where they
- turn OFF their own genes (as PER/TIM dimers do in Drosophila);
- turn OFF the gene inhibiting Bmal1 so this double-negative effect causes the level of the BMAL1 protein to rise.
There's a bit of jargon in there, too, but I think you can get the gist of what's going on with the production-inhibition-production cycle for the proteins.
So how does our body know when to time the clock? The SCN can be stimulated to modify the schedule because stimulation by light affects the shape (and thus effect) of proteins so that they inhibit production of the BMAL1 protein. Depending on timing, this could mean that you can shift your schedule forward or backward, but ultimately it's about 24 hours. I think that repeated exposure here also creates other cues internally to reinforce the behavioral patterns of mono- or bi-phasic sleep.
Obviously, there's more to this... sleep deprivation and other physiological and psychological factors can affect when we feel we need to sleep. Does the brain produce the light-modified protein in order to change the circadian rhythm? Does it inhibit production of the proteins, or create others that inhibit the inhibitors? I'll need to do more research.
But all of this applies to full-on circadian cycles and monophasic sleeping directly. It doesn't address ultraradian cycles, such as those encouraged by polyphasic sleeping.
Why am I asking this? I'll finish up in my next post on my observations of my personal polyphasic entrainment.
-sean
UPDATE - Sunday, Dec. 18th, 2005, 8:26 pm: Replaced the pasting from the article. I referenced the wrong part and didn't proofread enough... I was in a hurry. Thanks to mc for pointing it out.
posted by Sean @ 12/17/2005 01:02:00 PM
3 Comments:
You are right with "sleep memory". Those proteins you quote remember your current circadian state. To shift their timing you need to do some smart prodding. You need to understand the PRC, your own rhythms and a bit about sleep physiology. Yet the cycle is indeed basically circadian, i.e. you won't easily enter rhythms less than 24 and more than 25 hours long.
Your biphasic cycle built up on a typical siesta system with hours shifted towards a rhythm that is little known to pre-Internet people. Slightly unhuman :)
If you still use an alarm clock in the morning in the biphasic system, you can be working with a slight sleep deprivation. But this may still be healthier than a monophasic system if it results in a higher degree of deprivation. Probably you can sense it best by the way you feel in the morning. The better you feel, the lesser the adverse effect of the alarm.
As for polyphasic sleep, it will not work precisely because of this damn "sleep memory". You probably hope to hook up to ultradian rhythms, but ... I do not think anybody really figured out the biological basis for an ultradian oscillator. Even worse, good models show that it can be explained by homeostatic NREM vs. REM buildup. In other words, there might be no inherent phase-dependent oscillator. Just two homeostatically exclusive processes. In simpler terms, if your circadian and homeostatic sleepiness is high, you can fall asleep at 1 am or 5 am, and you will still always beging with a NREM build up and gradually move to REM **INDEPENDENT** of the actual hour you begin with.
This means that "hooking up" to ultradian cycle theorized by polyphasic sleepers is like hooking up to a virtual will-'o-the-wisp. As in the toilet joke: Trying to catch ones anal gas while its still warm :) (pardon my language)
I am awfully curious what your observation is. Perhaps you will indeed advance the science of polyphasic sleeping?
Did you try to write Stampi? He is a nice guy, perhaps would be interested in your observations? Or pherhaps he is tracking some blogs to collect inspiration? :)
btw: you pasted the fruit fly part of the sleep genomics article instead of the human one :) - never mind, they are so similar that one can only gasp and wonder about the incredible biological importance of sleep across species (which polyphazers are trying to wreck)
are you still (attempted)polyphasic?
mc
You need to understand the PRC
I know you don't mean the People's Republic of China, ;) so please forgive my ignorance. What is this?
...if your circadian and homeostatic sleepiness is high, you can fall asleep at 1 am or 5 am, and you will still always beging with a NREM build up and gradually move to REM **INDEPENDENT** of the actual hour you begin with.
So, what you're saying is that sleep always proceeds through the usual steps before reaching REM, correct? Is the rate of the phases of sleep affected at all? I ask because someone on the uberman mailing list has stated that Stampi actually found that all stages of sleep occurred, just in a shorter time frame. I have yet to read Why We Nap (haven't gotten to the library yet), so I cannot be sure.
Did you try to write Stampi?
I've certainly considered it, and even briefly looked for contact information, but never found anything. I would very much like to converse with him.
btw: you pasted the fruit fly part of the sleep genomics article instead of the human one :)
Whoops. Thanks for that. Fixed now.
are you still (attempted)polyphasic?
Yes, though not pure 6x20 by any stretch.
Thanks for the feedback and info. I'm always pleased by the leads and info you provide.
-sean
PRC stands for "phase response curve" (I recommended that to study in earlier posts I recall). Czeisler has plotted one very precisely not so long ago, so PRC+Czeisler in Google should get you there fast I hope.
Stampi is naturally very right about "compression". Those are all homeostatic beasts. You do not get enough, the body will counteract.
If you are facing ice-bergs in the sea, you will naturally want to compress your sleep and live. Thus Stampi can save your life with an ActiWatch or so. If you want to get maximum hours awake per day, you can also try compression. But I assume tacitly that you want maximum PRODUCTIVE hours per day. In such a case, tossing the alarm clock down the drain is the best solution (sewege works people might disagree)
Last but not least, "productive and alert" is not the entire picture. Creativity and learning is what probably earns you money for a happy life. Those will suffers dismally!
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