It was February 14th, 1972 when Michel Siffre kissed his wife goodbye and embarked on a self-experiment, where he would spend the following 6 months in complete isolation in a cave in Texas.
He couldn't tell time because his setting was devoid of all time cues. How this impacted his biology? I discuss about it in the video. Please be kind and hit the thumbs up button if you like it!
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@cristiCristi Vlad, Self-Experimenter and Author