Thread: Human Sleep Cycle

I came to the conclusion that the human sleep cycle is not based on cultural standards.
The human sleep cycle is a biological human characteristic based on the earth's 24 hour rotation period.

1.
If we slowed the earth down to a 36 hour rotation period, we could asume that the length of daylight and night would increase in proportion.
There is about an average of 14 hours of daylight, and 10 hours of night in a 24 hour period.
Therefore. there would be about an average of 21 hours of daylight, and 15 hours of night in a 36 hour period.

Regardless of the new 36 hour day, humans would still abide by a sleep cycle that they biologically (not culturally) evolved with.

2.
If you take a person, and lock him in a dark room with no windows, that person might not sleep at the exact time that it is night outside. However, I would hypothesize that the person would abide by the biological human sleep cycle. Meaning that the amount of sleep cycles this person would go through would be roughly the same as a person outdoors.

3.
If earth had always had a 36 hour rotation period, humans would have evolved according to a cycle of 15 hours night, and 21 hours daylight. Because I have concluded that the human sleep cycle is biologically based on the 24 hour rotation of the earth. I have also concluded that if the human evolved on a 36-hour earth, the human would have evolved to have a different sleep cycle. Our bodies would probably have evolved to match the day and night cycles of a 36-hour earth.

Take away artificial lighting and I think you have something, the question is...what's the question?

I have not explained the question or the scientific method that we used to to arrive at our conclusion. I have only explained the conclusion.

The question is about the existence of a human sleep cycle. Whether or not we humans have a natural sleep cycle. If so, whether or not our cycle depends on the rotation of the earth.

If the earth took 36 hours to rotate instead of 24, would humans still abide by the same current sleep standards we have on a 24-hour earth?

Being that we evolved on a 24-hour earth, the answer is yes.
If we have evolved on a 36-hour earth, we would have a different sleep cycle.
The conclusion is that there is a sleep cycle. It is a biological cycle based on humanity's evolution on a 24-hour earth.

I assume your refering to the night and day changes. Investigate the sleep cycles of those close to the north pole. Where night and day are not as much a factor. I for one prefer to work at night and sleep more during the day.

Why focus on exeptions?
There is a general standard for humanity as a whole.
Generally, the cycle repeats itself in the area of every 24 hours.
It is typically no different if you live in antarctica or have nocturnal tendencies.

Originally Posted by cool skill

Why focus on exeptions?
There is a general standard for humanity as a whole.
Generally, the cycle repeats itself in the area of every 24 hours.
It is typically no different if you live in antarctica or have nocturnal tendencies.

Well someone needs to tell my dog, she sleeps at random times during the day and night. I have to agree that your theories are correct, I just like the exceptions better

Actually the typical human cycle is over 24 hours, and is reset by daylight. The cycle can also be re-set for most people by artifical light with limited sucess. Many people can adapt easily to an inverted cycle, but most can not tolerate significant change to the length of the cycle.

Sailors on submarines which used an 18 hours day suffered from disorientation and decreased efficiency; I don't know if this is still the practice on submarines.

Researchers on the poles can lose the ability to function socially and professionally if they indulge in free-wheeling; that is, working on a completely idiosyncratic cycle.

Workers on rotating shifts are more efficient and have fewer accicents if their shifts are moved later [first, second, third] rather than the reverse.

The length of time available for sleep is also important; soldiers on split shifts, with no more than 6 hours down time, can start to exhibit irrational, paranoid, and even 'psychotic' behavoir. Interestingly, this does NOT seem to be related to the amount of time the individual actually sleeps.

I am not aware of scientific studies on this point, but I believe that the average cycle changes with age. Adolescents are now believed to be naturally late-risers; this suggests that the natural cycle at that age is 26 or 27 hours, or a lower sensitivity to light cues to reset the clock.

interesting matter guys!

Maybe insanity was onto something when she mentioned her dog (you're a girl right, or am i mixing up different people now? :wink: ). My parents have cats, and if I'm not mistaken cats are active by night and sleep most of the day. Now that the cats are getting older they seem to sleep more by day, but when they were young they were allways very active at daylight (when they're supposed to be sleeping?). Did they adept our human sleep cycle? If so, then this would swing a nature/nurture debate about sleepcycles to the side of nurture.

Originally Posted by Pendragon

interesting matter guys!

Maybe insanity was onto something when she mentioned her dog (you're a girl right, or am i mixing up different people now? :wink: ). My parents have cats, and if I'm not mistaken cats are active by night and sleep most of the day. Now that the cats are getting older they seem to sleep more by day, but when they were young they were allways very active at daylight (when they're supposed to be sleeping?). Did they adept our human sleep cycle? If so, then this would swing a nature/nurture debate about sleepcycles to the side of nurture.

Some claim I have PMS at times, but nope I'm not a girl. Not sure I even resemble one. If I am I must also be a lesbian as I have a wife

sorry m8 I dunno why I thought it! :wink: Maybe I mixed you up with a female moderator at itsallpolitics.com. And maybe in some way it's a compliment: girls are known to have better communicative skills than guys, and communication is really what it's all about on a forum :P

Originally Posted by Pendragon

sorry m8 I dunno why I thought it! :wink: Maybe I mixed you up with a female moderator at itsallpolitics.com. And maybe in some way it's a compliment: girls are known to have better communicative skills than guys, and communication is really what it's all about on a forum :P

Your thinking of 2112 perhaps? She is also a member here. I'm not sure how good my communication skills are really, never had anyone make a comment. Women can be confusing at times, at least in my experience. Men often will base ideas more on logic and not emotion.

I think CS has something here.

I have had a "normal" sleep cycle untill recently. Normal being awake mostly in day light and sleep during the night.

However now that I have a different job, were I work a 12hr shift graveyard. My sleep cycle has been disturbed. I have to sleep during the day, and I sleep an avg. of about 5 hrs during work days. The job is shift is set up were we work four days one week and 3 days the next. Making it difficult to remain with a normal sleep cycle during days off. Also the shift that I work works everyother week end. For example. I work: monday, tuesday-off on whensday-thursday-on again friday,saturday,sunday. Sunday being the first day of the three day week. I'm then off on monday-tuesday. on wendsday-thurdsday. and get the weekend off. And it's starts all over again.

Thus my sleep cycle is totally out of wack. I'ts about 3AM right now, and instead of being sleep, I'm typing away awake. I felt sleepy about 9PM last night and slept till about a 15 min. ago. I more than likely be up till 8Am today, and I must get to sleep during the day today in order to have enough energy to be up all night. This is the work week end.

At the begining of this job, I was not getting any if hardly sleep during the day, headaches were frequent, and so was imsonia during the days off. You could say now that I have no sleep cycle, as I only sleep when I do feel tired and I try to sleep at least 5 hrs before going to work. On days off I may sleep at least 2-3 hrs during the day, unless it's the first day off were I sleep 5-8 hrs.

Power sleeps. At times when I do work, I must do things that will take away from sleep time, but I try and sleep at least 2hrs before heading to work.
Another thing I try is sleep depravation. I intend to soon go to some college classes, that will start early mornings after work, and off about 12PM so I can sleep at least 4-hrs before going to work. So far on a work cycle I've been able to stay up, till 11AM then I just feel so damned tired I can fall sleep on the computer without getting to bed. There's a younger guy at work, who's going to college, and when at work, this poor fella looks all beat & tired, before the start of the shift, his energy though seems to pick up close to quiting time. I'd bet he's hardly geting any sleep. if any during work cycles.

Godless.

We used to have a cat for whom I had to get up some 3 or 5 times each night, at no particular hours, no order.
I ended up quite drained, a bit disoriented, tired, but I actually got used to functioning on that low level.

Light plays a major role in controlling circadian cyles.

http://www.rockefeller.edu/pubinfo/light.nr.html

Godless:
Graveyard is absolutely the worst shift; swing is fine, if the home environment allows sleeping "late".
I've worked graveyard, so here are some tips.

Darken the bedroom, or wear an eye-shade; sleep in a room on the North side of the house [if you are in the northern hemishere]. If you are tired enough to fall asleep in full light, you need at least 8 hours sleep, probably more.

If you get disturb by noise, try leaving the radio on low as a counter-irritant [this does not work for me].

Go to bed when you come home from work, rather than in the middle of the day.

Eat before going to work and before going to bed; do not eat much at work in the middle of the night. Do not have any caffiene except at the beginning of your day. Stay away from sugar.

Exercise at the beginning of the day and when you get tired at work. Do NOT exercise before you go to bed.

If you have trouble falling asleep, you could try to set your cycle with a nighttime cold medication. Try it for a few days, preferably on the start of your days off.

Keep your sleep cycle as consistent as possible; do not try to return to a "normal" cycle on your days off. This is very important; most people can adapt to any CONSITENT 24 HOUR cycle, but not to a broken pattern.

I love working off-shifts.

J

Thanks for tips, I've tried sleeping pills on days off but I find that I dont want to get hooked on them. I take melatonin it works just fine, but they do leave me sleepy if I don't get enough sleep. So I also use them in off days.

I do try to eat before going to work, I find this gives me plenty of energy to make it through the night. And I also like eating breakfast after work, I find that this makes me sleep real good till about 2-3pm.

Thanks again.

Godless.

I use to work 12 hour graveyard shifts watching over DB servers that had much to do with the stock market. 7 pm - 7 am or 8 pm to 8 am.

I had a studio apartment right on the street, it sucked. I would always hear people doing stuff. Road construction was really brutal. I found Valarine helped a bit and didn't cause a hangover feeling. Benadryl will also put you to sleep, but may leave you a little hung over. Coffee a few hours before bedtime can work also, it has a reverse swing that will make you tired. Alcohol would do the opposite.

People are so different when it comes to body chemistry, it's really hard to say for sure what would work.

Quote:
"2.
If you take a person, and lock him in a dark room with no windows, that person might not sleep at the exact time that it is night outside. However, I would hypothesize that the person would abide by the biological human sleep cycle. Meaning that the amount of sleep cycles this person would go through would be roughly the same as a person outdoors."

--> actually the day-night circle increases to around 25 hours. This is called the circadianic rhytm

If you take a person, and lock him in a dark room with no windows, that person might not sleep at the exact time that it is night outside.

Actually if you take a person and lock him like so, he/she would go mad. His mind will not know time, he/she won't have a clue, what time of day/or night it is, and since he be going mad, he may sleep very little/or alot more than usual. He may start wondering if he/she is dead.

Godless

Originally Posted by Godless

If you take a person, and lock him in a dark room with no windows, that person might not sleep at the exact time that it is night outside.

Actually if you take a person and lock him like so, he/she would go mad. His mind will not know time, he/she won't have a clue, what time of day/or night it is, and since he be going mad, he may sleep very little/or alot more than usual. He may start wondering if he/she is dead.

Godless

A few decades ago a group of peolpe stayed in apartment with no windows or clocks for several months. The light conditions where exactly the same all the time. After a while their day-night-cycle shifted to ca. 25 hours. the average sleeping time was something around 8 hours.

Of course it was a group of peolpe and they have not stayed in the dark, but under the same light conditions all the time.

But has anyone ever tested if the rhythm changes with age? Adolescents stay up late and sleep late whenever they can; do they have a significantly longer cycle, or have adults just been more thoroughly conditioned?

Originally Posted by j

But has anyone ever tested if the rhythm changes with age? Adolescents stay up late and sleep late whenever they can; do they have a significantly longer cycle, or have adults just been more thoroughly conditioned?

the sleeping time decreases with age. But I cannot tell you exact numbers

the sleeping time decreases with age.

Not allways. By experience my mom whom is 72 now sleeps lots more than when she was younger, she's not tired she claims, she falls asleep watching boring tv shows.

But seriously she's sleeps irregularly, likes taking naps after eating, and has a good overnight sleep till about 7-8am.

Me on the other hand don't get much sleep. But not because of age, but because I work a graveyard shift. Though now that i'm older I require less sleep to feel rested.

Godless

well, science is just statistics you know. We are talking about means and nothing more. Maybe in the future, when quantum logic is an accepted part of psychology and the social sciences, we will know better