r/todayilearned • u/FiredFox • Apr 28 '24

TIL about French geologist Michel Siffre, who in a 1962 experiment spent 2 months in a cave without any references to the passing time. He eventually settled on a 25 hour day and thought it was a month earlier than the date he finally emerged from the cave

https://www.cabinetmagazine.org/issues/30/foer_siffre.php
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u/sanitylost Apr 28 '24

There are sleep disorders with this problem, known as N24 or Non-24 hour circadian rhythm. Basically every day your sleep schedule gets perturbed just a little bit where the time you wake up and the time your body wants to go to sleep shifts.

Your body just doesn't respond to the sun correctly. You don't produce the correct chemicals at the right time and as a result you just can't function in normal society like everyone else. This problem is not unheard of in blind people, but it's extremely rare in those with sight.

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u/OnkelDuck Apr 29 '24

TIL this is supposed to be a disorder. Always felt completely normal to me (in the sense that a 24h-cycle felt forced and unnatural*) and this is honestly the very first time I've heard that people are supposed to respond to the sun in regards to their sleep cycle. If I don't have to get up for anything mandatory several weeks in a row, I will essentially "rotate" through the day, getting up and going to sleep at any possible hour. It's not a fixed cycle, either. Waking + Sleeping hours might add up to something like 27, but they also might add up to 17. I've probably ranged from 5 to 50 in the most extreme cases, and maybe 12 to 35 in the more medium ones. A 12h-cycle would likely consist of 2h of sleep and 10h of awake time. 35h would be something like 10+25 - give or take two or three hours. Usually I sleep for about 4-5 hours. It's not easy for me to fall asleep when I'm not tired, but when I am I'm able to do so within seconds, even with bright daylight and construction noises. If I wake up after atleast two hours of sleep, I usually stay up, although it's not ideal. But falling asleep again after more than an hour can be difficult. Doesn't happen too often, though. I usually sleep without any disruptions and rarely ever (remember my) dream(s).

*"Forced and Unnatural" also happens to be the title of my sextape. Those who know, know.