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1962 Cave Experiment Reveals Human Clock's Surprising Flexibility

4/7/2025

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Summary

Story summary

In 1962, French geologist Michel Siffre embarked on a remarkable journey, spending 63 days in a glacial cave, cut off from the outside world. His groundbreaking experiment unveiled the astonishing ability of the human internal clock to stretch beyond 24 hours, paving the way for chronobiology and reshaping our understanding of sleep disorders and human endurance in extreme conditions.

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Story summary

In 1962, French geologist Michel Siffre embarked on a remarkable journey, spending 63 days in a glacial cave, cut off from the outside world. His groundbreaking experiment unveiled the astonishing ability of the human internal clock to stretch beyond 24 hours, paving the way for chronobiology and reshaping our understanding of sleep disorders and human endurance in extreme conditions.