14/08/2015
Everybody knows people who seem to bumble through life with no sense of time — they dither for hours on a “quick” e-mail or expect an hour’s drive to take 20 minutes. These people are always late. But even for them, such minor lapses in timing are actually exceptions. We notice these flaws precisely because they’re out of the ordinary.Humans, like other animals, are quite good at keeping track of passing time. This talent does more than keep office meetings running smoothly. Almost everything our bodies and brains do requires precision clockwork — down to milliseconds. Without a sharp sense of time, people would be reduced to insensate messes, unable to move, talk, remember or learn.“We don’t think about it, but just walking down the street is an exquisitely timed operation,” says neuroscientist Lila Davachi of New York University. Muscles fire and joints steady themselves in a precisely orchestrated time series that masquerades as an unremarkable part of everyday life. A sense of time, Davachi says, is fundamental to how we move, how we act and how we perceive the world.Yet for something that forms the bedrock of nearly everything we do, time perception is incredibly hard to study. “It’s a quagmire,” says cognitive neuroscientist Peter Tse of Dartmouth College.The problem is thorny because there are thousands of possible intricate answers, all depending on what exactly scientists are asking. Their questions have begun to reveal an astonishingly complex conglomerate of neural timekeepers that influence each other.New findings hint that the brain has legions of assorted clocks, all tick-tocking at different rates. Some parts of the brain handle milliseconds and others …