As It Happens

These volunteers spent 40 days in a cave with no sunlight or way to tell time

Montreal's Marina Lançon was one of 15 people who volunteered to spend 40 days in a French cave without any way to tell the time or communicate with the outside world — all in the name of science. 

Montreal's Marina Lançon was among the 15 participants in the Deep Time research experiment

Marina Lançon, pictured in the centre with a blue bandana and gray sweater, emerges from the Lombrives Cave in France with 14 other people after 40 days underground. (Renata Brito/The Associated Press)

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The sunlight was blinding when Marina Lançon emerged from a cave in southwestern France for the first time in 40 days. 

The Montreal expedition guide was one of 15 people who volunteered to spend 40 days in the cold, dark Lombrives cave without any way to tell the time or communicate with the outside world — all in the name of science. 

They finally came out on Sunday wearing special sunglasses to protect them from the light.

"When they came to announce the end of the experiment after 40 days in the cave, it was kind of a shock. I remember thinking, like, 'Oh no, already?'" Lançon told As It Happens host Carol Off.

"Time went by so fast and I still had, like, so [many] things I wanted to do in the cave."

Members of the team taking part in the Deep Time study gather around a table in the Lombrives Cave in Ussat les Bains. (Human Adaptation Institute/The Associated Press)

The cave dwellers — seven women and eight men of different ages and backgrounds — were volunteers for the Deep Time research project, led by the Human Adaptation Institute based in France to gauge how humans adapt to extreme environments with no ability to measure time. 

"Our future as humans on this planet will evolve," Christian Clot, project co-ordinator and participant, said. "We must learn to better understand how our brains are capable of finding new solutions, whatever the situation."

It was dark, cold and wet in the cave — about 10 C most days with 100 per cent relative humidity and no natural light. 

The participants had no access to clocks, phones or communication devices. They had no idea what time, or even what day it was, and no way to find out what was happening in the outside world. 

Their only technology were cameras and devices used to track their movements and measure their sleep patterns. 

Members of the study are seen exploring the caves, which were dark, cold and humid. (Human Adaptation Institute/The Associated Press)

They were asked to eat, sleep and wake up whenever it felt natural. As a result, everyone ended up living according to their own personal clocks.

When the experiment came to an end, Lançon says she thought she had been in the cave for 29 days because that's how many sleep cycles she had experienced. 

"Some other persons in the group, they were at Day 23, for example, and others at Day 31," she said. "So we really had different cycles."

Participants study and eat in the cave they called home for 40 days. (Human Adaptation Institute/The Associated Press)

That made it difficult to perform the tasks expected of them in the cave — things like fetching water, documenting signatures on the wall from previous cave explorers, and clearing out the debris and trash.

"All those tasks need to be several people, like three or four people. So that was difficult because you never knew when you woke up, who's waiting for you or what you need to do,"  Lançon said. 

The team celebrates as they emerge from the Lombrives Cave after 40 days on Sunday. (Renata Brito/The Associated Press)

Nevertheless, Lançon said she enjoyed her time in the cave, and was in no rush to leave. She got along well with her fellow volunteers, and says she never got cabin fever or even a strong desire to leave. 

That wasn't the case for everyone.

Johan Francois, a math teacher and sailing instructor, said he sometimes had "visceral urges" to abandon the experiment, and would run 10,000-metre circles just to stay active.

Still, he admitted the experience had its benefits. With no daily obligations and no children around, the challenge was "to profit from the present moment without ever thinking about what will happen in one hour, in two hours," he said.

Two-thirds of the participants expressed a desire to remain underground a bit longer in order to finish group projects started during the expedition, said Benoit Mauvieux, a chronobiologist involved in the research.

Asked if she'd ever go back, Lançon said: "Why not?" 

"Maybe in a few years," she added. "But for now, I'm just happy to be out."

Written by Sheena Goodyear with files from The Associated Press. Interview produced by Mehek Mazhar. 

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