ladbible homepage
ladbible homepage
  • Home
  • News
    • UK
    • US
    • World
    • Ireland
    • Australia
    • Science
    • Crime
    • Weather
  • Entertainment
    • Celebrity
    • TV
    • Film
    • Music
    • Gaming
    • Netflix
    • Disney
  • Sport
  • Technology
  • Travel
  • Lifestyle
  • Money
  • Originals
    • FFS PRODUCTIONS
    • Say Maaate to a Mate
    • Daily Ladness
    • UOKM8?
    • FreeToBe
    • Citizen Reef
  • Videos
  • Advertise
  • Terms
  • Privacy & Cookies
  • License Our Content
  • About Us & Contact
  • Jobs
  • Latest
  • Archive
  • Topics A-Z
  • Authors
Facebook
Instagram
X
Threads
Snapchat
TikTok
YouTube
Submit Your Content Here
  • GAMINGbible
  • LADbible Group
  • UNILAD
  • SPORTbible
  • Tyla
  • FOODbible
  • UNILAD Tech
Man who lived in cave with no concept of time went back in for six months and effects were unbelievable
Home>News>Science
Published 18:48 19 Mar 2025 GMT

Man who lived in cave with no concept of time went back in for six months and effects were unbelievable

Michel Siffre conducted the isolating experiment twice in his life

Brenna Cooper

Brenna Cooper

google discoverFollow us on Google Discover

A man who experienced astonishing side effects after living in an underground cave did the unthinkable by going back to spend another six months down here.

Given the fact that our lives are heavily regimented by a 24-hour cycle, living with the complete absence of time sounds pretty jarring — or even torturous. But for French explorer Michel Siffre, secluding himself underground in a cave wasn't a nightmare scenario but instead a fun experiment.

So fun that after emerging from his two-month subterranean sabbatical in 1962 he decided to head on back down there for a whopping six months in 1972.

Here is what he was able to discover about the human body and it's internal body clock.

Advert

Michel Siffre's 1972 cave experiment

In 1972 Siffre, then aged 33, made the decision to spend six months living in Midnight Cave, Texas. Like his previous 1962 experiment, the hypothesis was simple: what impact does time have on the body and it's human circadian rhythms (our internal body-clock)? And, once deprived of an external indicator of time, would the body's sleep-wake cycle be impacted?

And it was here that the field of human chronobiology was formed.

What were the aims of Siffre's experiment?

Like his first experiment, Siffre would retreat into the cave with limited communication to the outside world, he was able to contact the team monitoring him but not vice versa, and conduct various experiments while being watched.

Daytime would be determined whenever Siffre woke-up and he slept whenever he felt the need to.

Explaining his decision to head back underground a decade after his initial experiment during an interview with a 2008 interview with Cabinet Magazine, the explorer said he wanted to understand if there were any changes in how his 'brain perceives time' since his first experiment and the '48-hour sleep/wake cycle'.

"I decided I would stay underground for six months to try to catch the forty-eight-hour cycle," he said.

Michel Siffre ahead of his 1999 isolation experiment (PHILIPPE DESMAZES/AFP via Getty Images)
Michel Siffre ahead of his 1999 isolation experiment (PHILIPPE DESMAZES/AFP via Getty Images)

What did Siffre discover during his six months underground?

Siffre would indeed succeed in catching the elusive 48-hour sleep wake cycle during his second underground excursion, although not regularly.

"There were two periods where I caught the forty-eight-hour cycle—but not regularly," he said. "I would have thirty-six hours of continuous wakefulness, followed by twelve hours of sleep."

Perhaps more interesting is the fact that Siffre wasn't able to tell the difference between the longer and shorter days he experienced in the cave.

"There was no evidence that I perceived those days any differently. Sometimes I would sleep two hours or eighteen hours, and I couldn’t tell the difference," he added.

Siffre recovering after one of his underground experiments (Keystone-France/Gamma-Rapho via Getty Images)
Siffre recovering after one of his underground experiments (Keystone-France/Gamma-Rapho via Getty Images)

The experiment would also have negative impacts on Siffre's mental wellbeing, which began to deteriorate during his time in the cave.

During a 1975 recollection of his experience, Siffre the Frenchman explained feeling a sense of overwhelming 'lethargy and bitterness' due to isolation.

The moral of the story? Humans cannot understand time without external stimuli and that being alone underground is very boring.

Featured Image Credit: Patrick Durand/Sygma via Getty Images

Topics: Science, Community, Weird

Brenna Cooper
Brenna Cooper

Brenna Cooper is a journalist at LADbible. She graduated from the University of Sheffield with a degree in History, followed by an NCTJ accredited masters in Journalism. She began her career as a freelance writer for Digital Spy, where she wrote about all things TV, film and showbiz. Her favourite topics to cover are music, travel and any bizarre pop culture.

X

@_brencoco

Recommended reads

Donald Trump storms out of interview over exchange with reporterNBCDiagnosed psychopath explains why 'normal people' can never spot themLADbible OriginalsEx-Playboy star Kendra Wilkinson's life now as she shares 'heartbroken' updateDenise Truscello/WireImageTop surgeon issues chilling warning after man burned hole in nose through drug useCadogan Clinic

Advert

Choose your content:

26 mins ago
3 hours ago
4 hours ago
14 hours ago
  • NBC
    26 mins ago

    Donald Trump storms out of interview over exchange with reporter

    The US president slammed the NBC interviewer as 'crooked' before calling it quits in the barn

    News
  • Ulrik Pedersen/NurPhoto via Getty Images
    3 hours ago

    Denmark issues update after Christian Eriksen collapses on pitch for second time

    Players were left crying on the pitch after the shocking scenes

    News
  • JUAN MABROMATA/AFP via Getty Images
    4 hours ago

    Madeleine McCann police handed 'bombshell' new files linked to suspect Christian Brueckner

    British investigators have reportedly received a dossier containing fresh information relating to the main suspect

    News
  • Jamie Squire/Getty Images
    14 hours ago

    Nine injured after shooting near England team's World Cup base in Kansas City

    Police are investigating after multiple people were injured in a shooting less than four miles from England's base

    News
  • What happened to man who lived in cave with no concept of time
  • Unbelievable effects man who lived in cave with no concept of time ended up experiencing after two months
  • Man who lived in cave with no concept of time ended up experiencing unbelievable effect on his body clock
  • Incredible moment man who lived inside cave with no concept of time emerges after two months in pure darkness