I always heard that you should sleep with your head facing whatever direction for better sleep quality. I know that some people do know where the Mecca is, or maybe north, but I am pretty sure this knowledge is not “automatic”.
If a bedroom is perfectly dark, with no air currents, lighting differences or noise, being the only variable the direction where the sleeping person is facing… Would there be any differences in sleep quality if the person sleeps facing north, south or any other direction?
I’ve heard that before, in a foggy past, but probably not since the 50’s. You’re talking about a kind of a biological Feng Shui.
It would be hard to test, because one’s slumber tends to be somewhat variable from one night to another, with a lot of different factors that could also be contributors.
That only leaves 2 effects I can think of.
One is Coriolis force, which is a pseudo-force that results from the earth’s rotation. But Coriolis force mainly affects large systems (like storms), and it’s difficult to even detect at smaller scales like human bodies, bathtubs and toilets.
That leaves magnetic field, which of course is strong enough to measure easily (a compass does that). There is some evidence that suggest cattle orient their bodies along magnetic field lines, so it’s not inconceivable that it affects human behavior. But I haven’t heard of any such evidence for humans.
Couls be an interesting subject for a masters degree…
How many things “you always heard” ever have turned out to be right?
I have always heard that getting shot in the heart with a .44 Magnum will kill you. I really believe that.
Yeah, but who wants to test it?
To the overall question, I don’t think you can separate it from lighting, airflow, etc, because I think that’s where this theory comes from. For an extreme example, my husband and I actually sleep head to toe. He loves the fan and wants a much air as possible blowing on his face, whereas I feel like murdering someone if moving air touches my face while I’m trying to sleep.
In a less extreme case where the room had a natural light breeze instead of a directional fan, it’s entirely possible that we would each believe that a certain direction was best for sleeping – without understanding why we thought that.
I’ve found that keeping my face out of the cat on my pillow is the best direction.
Citation to a double blind study?
I can cite a blindfold study. Will that do?
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No.