Hichory dickory dock

Finally going through my old gmails one by one. This BBC report caught my eye in Oct last year. And talking of time, half of this year is almost over. And its almost just yesterday that a colleague had mentioned having a new year's party, which we've been postponing every month, - and now six months are almost over. I try not to think about time too much. It scares me. The rate at which it rushes past, especially when one is working. One day in the office melts into another, one deadline into next..and all around things are changing... Its hard to get a grip on the bigger picture. And that is somehow scary. Oh well, enough waffle. Here is the article:
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Time out of mind

We can't touch time, or smell it. Yet it is utterly inescapable. But, research shows, time is - at least partly - something we control in our heads.
It's four in the morning, and schoolgirl Bethany McQuerry is starting her homework. Her dad, Clay, does the family's washing before going to the 24-hour supermarket. Meanwhile, Bethany's mum and brother, Janelle and Casey, sleep on.

But Bethany is no swot and Clay is no housework obsessive. They just wake up early every single day, whether they like it or not - it's as if they have permanent jet lag.

Bethany and Clay have to get things done early in the morning, because they also fall asleep in the early evening. The difference in timekeeping has divided the family, from North Carolina, US.

"There have been times when I wished we would function the same as other families," says Janelle. "It does make it hard when you're wanting to be together."

Only recently did Clay discover there was a biological explanation for his and Bethany's unusual behaviour, known as ASPS, or Advanced Sleep Phase Syndrome - a disorder of the body clock that shifts their day forward.

Caveman experiment

The body clock determines our most fundamental behaviours: when we wake up, go to sleep, and eat. But it also determines our physical strength and performance over a day.


However basic the clock's functions seem to us today, its existence was only proved in 1962, by a French caver.
Michel Siffre had been planning to study the movement of a glacier through an underground cave, when he realised the enormous potential of his experiment for the field of biology.

"I had the idea of my life: I decided not to take a watch in the cave. I decided to live without time cues," he said.

By isolating himself underground, away from daylight, clocks or routines, he hoped to discover whether the body had its own rhythm. And if so, what it was.

"I decided to live following my feelings of hunger, my feelings of going to sleep. In the cave it's always dark, then your body follows its own sense," said Mr Siffre.

His plan was to call a surface-team of assistants every time he woke, ate, exercised or urinated so every one of his biological functions could be monitored.

Each time, he would give an estimate of the date and time, and the surface-team would compare this with the real time. This he did for two months, before emerging into the real world. Mentally, he had completely lost track of time, but the results showed his body had kept up a rhythm.

While the length of Siffre's waking days varied widely, from 40 hours to just six, a clear pattern emerged. The average length of his days was just over 24 hours. Evolution, it seems, had tailored his body's clock to run closely to the Earth's day length.

It's now known that the body clock is controlled by a tiny pea-sized organ in the brain called the suprachiasmatic nucleus, or SCN. This tiny region commands a chain of chemical and nervous instructions that ripple through the body, controlling how each organ and tissue functions over the 24-hour day.

It's this mechanism that has gone wrong in the case of Clay and Bethany McQuerry. Their early rising is due to the inheritance of a single mutation that throws the whole body clock off kilter.

Does time fly?

While the body clock keeps the rest of us "in synch" with the world around us, that's not our only experience of time. We also have a completely separate sense of time passing.

Mostly, we're pretty good at estimating durations of time - how long you've been online, for example. But people also speak of "time flying" when they're enjoying themselves, or slowing right down in perilous situations such as car crash.


But is there any real distortion of perceived time here, or are people re-inventing their experiences after the event?
Psychologist Dr David Eagleman, of the University of Texas, recently set out to nail this assumption, and a BBC film crew was there to record it. He asked volunteer Jesse Kallus to perform a terrifying backwards free-fall of 33 metres.

If the anecdotes are correct, Jesse's perception of time would be slowed by the terrifying experience. But how could one monitor such a thing?

Mr Eagleman came up with a cunning device: the "perceptual chronometer", a wristwatch-like device which flicked blindingly fast between two LED screens.

Normally the flicker would be so fast Jesse could only see a blur. But if time slowed down for him, he might be able to discern the two different screens and read a random number on one of them.

"There's no way to fake this test," says Dr Eagleman, "because if time is not running more slowly, they can't see the sequence."

All Jesse had to do was jump, and read. As he ascended the 33ft metal cage no-one seemed to believe this curious experiment might work.


When Jesse landed, he noted he had seen "98". Dr Eagleman checked. In fact the number was 96. Not quite spot-on, but the two numbers look very similar on a digital screen.
"I would have loved it if he had seen the numbers exactly," says Dr Eagleman. "But this at least suggests to me that he's able to take in information faster than he was before".

Further jumps got similar results - all suggesting that time did seem to slow down for Jesse during the jump.

So while time on the clock may be constant, the time in one's brain is elastic and personal - something to remember in a boring meeting when time seems to grind to a halt. Time is not simply a fourth dimension in which we exist. It's something we, at least partly, create in our minds.

See the original at the link