French Scientist Spent 180 Days In Pitch-black Cave In 1972 Experiment — And He Noticed One Major Change In His Body

In a world governed by ticking clocks and buzzing alarms, the idea of living entirely beyond time sounds like a thought experiment reserved for blockbuster science fiction—or maybe for the deeply introspective. What would happen if someone completely removed themselves from all temporal cues—no sunrises, no sunsets, no connection with the outer realm? For most, it would be a dystopian world. But for one French explorer, it became an extraordinary opportunity not only to challenge human endurance but to stumble into one of the most stunning scientific breakthroughs of the 20th century, stated LADBible.

In 1962, 23-year-old French speleologist Michel Siffre descended into a glacial cave in the Ligurian Alps, intending to spend two months in complete isolation—no clocks, no calendar, and no contact with the world except a quick phone call to report his physical and mental state. What started as a mere geological expedition turned into a revolutionary human experiment that would unknowingly originate a completely new field of science— human chronobiology. Siffre recalled, "You have to understand, I was a geologist by training. In 1961, we discovered an underground glacier in the Alps, about seventy kilometers from Nice. At first, my idea was to prepare a geological expedition and to spend about fifteen days underground studying the glacier, but a couple of months later, I said to myself, 'Well, fifteen days is not enough. I shall see nothing.' So, I decided to stay two months. And then this idea came to me—this idea that became the idea of my life. I decided to live like an animal, without a watch, in the dark, without knowing the time," according to Cabinet magazine.

His idea was no rocket science. He wanted to let his body dictate his days—sleeping, eating, thinking, and existing without any external stimulus to mold his routine. But, intriguingly, what happened during those 63 days was anything but basic. Siffre’s makeshift camp was nestled beside an underground glacier. He spent most of his time reading, writing, and conducting self-tests—including a psychological evaluation where he counted from 1 to 120 at the rate of one number per second. In a bizarre series of events, the perception of time had slowed for him dramatically.

He shared, "That’s a big question that I’ve been investigating for forty years. I believe that when you are surrounded by night—the cave was completely dark, with just a light bulb—your memory does not capture the time. You forget. After one or two days, you don’t remember what you have done a day or two before. The only things that change are when you wake up and when you go to bed. Besides that, it’s entirely black. It’s like one long day," stated Cabinet magazine.

He had lost 25 days—psychological time had literally compressed. He remarked, "There was a very large perturbation in my sense of time. I descended into the cave on July 16 and was planning to finish the experiment on September 14. When my surface team notified me that the day had finally arrived, I thought that it was only August 20. I believed I still had another month to spend in the cave. My psychological time had compressed by a factor of two." Unknowingly, Siffre had created the first-ever scientific protocol to study human circadian rhythms in the absence of time. It was known that animals had internal clocks—but Siffre proved humans did, too. His natural cycle extended beyond 24 hours, averaging about 24 hours and 30 minutes.