Studying the effects of Isolation and Sensory Deprivation: losing my sense of time

In 1962, French adventurer, explorer and scientist Michel Siffre having graduated from studying Speleology – the study of caves – chose to spend many months living underground in a cave.

I came across his story on the documentary video selection on my Air France flight to Montpellier for ESA training, in November last year.  I was blown away by his story… and his journey to investigate the meaning and passage of time.

Life underground in a cave

Siffre harbouring an interest in space exploration and living in the age of life in the nuclear fallout shelter, he soon found a way to contribute to the space age- investigating the effects of isolation by living underground in a cave, using himself as his test subject asking himself:

Could people cope with extreme isolation in a confined space? Without the Sun, what would our sleep cycles be like?

In 1962, the 23 year old Siffre lived in complete isolation for a period of two months, 375 feet underground inside a subterranean glacier in the French-Italian Alps.  Importantly he did not take a clock with him and had no daylight to mark the passing of time. Life inside the cave was difficult – shaded from natural light, in perpetual darkness, temperatures held below freezing, with 98 percent humidity. Siffre suffered from hypothermia.  He lived in fear, as a caveman of our past, not from the attack of sabre-toothed tigers, but of being killed by massive chunks of ice that regularly crashed down around his tent. During his 63 days underground, he had let go of reality only once- ‘singing at the top of his lungs and dancing the twist in his black silk tights’.

Discovering the human body’s internal body clock

On emerging, it was found that he had lost his sense of time – being shockingly incorrect and behind by 25 days in his estimation of the correct date.  Whilst underground in the cave, Siffre had used a longline to telephone his research assistants to provide his opinion of the date and time, every time he woke up, ate, and went to sleep.  Unknowingly, he had mostly remained awake for 24 hour periods before sleep.

Internal body clock?

However, whilst his mind had lost track of time, his body had kept its own rhythm to its own cycle.  Siffre had discovered the human body’s internal clock. Years later, some of my ESA research here focuses on the ‘circadian rhythm’ in humans – the biological process which displays an endogenous, entrainable oscillation of about 24 hours.  I am observing the effects of isolation, loss of the day-night cycle and chronic hypobaric hypoxia (lack of Oxygen) on our overwinter crew here.

When in doubt, go to Texas

1972 marked the next project, this time in Texas, USA.  Siffre, sponsored by NASA, had ventured back underground remaining for a period of 6 months in a cave in Texas.  This time, again investigating the passage of time without time cues, he observed something remarkable… that several people including himself adjusted to a 48 hour rather than a 24-hour cycle.

48 hour circadian rhythm?

Warmer and more luxurious than his previous stay underground, he had attached electrodes to his head, to monitor his heart, brain, and muscle activity.  Underground, without natural light, he ran experiments, listened to records, explored the cavern, and caught up on reading Plato. At Day 79, disaster struck as a crack widened in his mind, splitting his ability to remain in control.  He soon became extremely depressed- perhaps instigated by the malfunctioning of his record player broke and mildew began ruining his magazines, books, and scientific equipment.  He had become suicidal, finding his only solace in the companionship of a mouse that occasionally raided his supplies.  Like a scene out of the film the ‘Green Mile’, Siffre had tried to trap the mouse with a dish to make it his pet, but accidentally crushed and killed it, describing in his journal, “Desolation overwhelms me.”

The votes and results are in, from Texas It was found that during the first month, Siffre had fallen into regular sleep-wake cycles that were slightly longer than 24 hours. But after that, his cycles began varying randomly, ranging from 18 to 52 hours.  These results drove the further study into finding ways to induce longer sleep-wake cycles in humans—with potential benefit to soldiers, submariners, night shift workers and astronauts.

Astronauts underground

Ironic or not, today’s astronauts in training now spend time in a cave in Sardinia undergoing psychological training led by Loredana Bessone (HSO-AT) who is based at the Euorpean Space Agency’s European Astronaut Centre.

Our crew had undergone the same training in Paris.  I was satisfied to have been labelled as being ‘crazy’ by Loredana – crazy enough to winter over in Antarctica and crazy enough to go into space.

I think I share some of Siffre’s passion and sentiments, but do not share his passion for life in ‘sediment’ – caving – despite being born and brought up in Derbyshire – a limestone plate of UK, famous for potholing and caving.  I had enough of wriggling through the earth.  Being slim in stature, I naturally found myself stuck in slimmer spaces.

Melting time

My partner Kathy reinvigorated my love of Salvador Dali during our first year at medical school – where we had bunked off a lecture at St Thomas’ Hospital and walked across the grass to an exhibition by Dali located on the South Bank of the River Thames in London.  The £6 entry had been our last, but it was worth it.  My favourite Dali piece – The Persistence of Memory and The Disintegration of the Persistence of Memory (1954) – of the melting pocket watch concept – featured as a bronze cast and also in various paintings.  But even through lazy years sleeping through medical school, I hadn’t ever come closer to the sense and concept of unimportance of time in Dali’s works, than over the past few weeks here living at Concordia.

Our days grow increasingly shorter day by day, and the light is seeping away.  The sunset hangs low and lazy on the horizon even at 11am.

Maybe after all, Antarctica in winter is like living in a big dark cold ice cave.

Only time will tell.

Monsters of your mind

Discussing the prospect of winter at Concordia – our crew members all share the same intrepidation, anxiety and curiosity – knowing full well that in entering any cave – you never know what monsters sleep undisturbed hidden beneath in the unexplored dark corners of your mind, awaiting to be awoken.  Here begins one of the Earth’s most serious and extreme journeys of personal discovery – overwintering in the Antarctic interior.  My only hope is that Loredana was right.

I think Van Morrison sang it best… Here comes the night.

Please fasten your seat-belts, return your tray-tables to their upright position and  hold on tight… Brace… its going to be a rough landing.

Song of the day:

Here comes the night by Van Morrison.

Weather report:

2012/04/20 15:32

-65.4 °C Windchill -77.1 °C
-73.5 °C Pressure 632 hPa
1.7 m/s Relative Humidity 33 %
3.2 knots Wind Origin 311°


For further reading by/ about Siffre see:

  • Hors du temps. L’expérience du 16 juillet 1962 au fond du gouffre de Scarasson par celui qui l’a vécue, Julliard, 1963
  • Des merveilles sous la terre, Hachette, cop. 1976
  • Stalactites, stalagmites, cop. 1984
  • L’or des gouffres: découvertes dans les jungles mayas, Flammarion, 1979
  • Dans les abîmes de la terre, Flammarion, 1975
  • La France des grottes et cavernes, Privat, 1999
  • A la recherche de l’art des cavernes du pays Maya, A. Lefeuvre, 1979
  • Découvertes dans les grottes mayas, Arthaud, 1993