Think back to a time when something scary happened to you: maybe your car skidded on black ice; maybe you tripped and fell headlong down a flight of stairs; maybe you took a dare and went on the tallest roller coaster ride at the amusement park. How did time feel?
A brush with death taught David Eagleman about the mysteries of time and the brain. Burkhard Bilger takes us along on a journey of discovery in his tautly written and provocative New Yorker article profiling neuroscientist Eagleman and his work in "The Possibilian." Read all 10 pages. I am betting that you won't look at time, amusement park rides or eye witness testimony quite the same way. Excerpt:
"When David Eagleman was eight years old, he fell off a roof and kept on falling. Or so it seemed at the time....
In the years since, Eagleman has collected hundreds of stories like his, and they almost all share the same quality: in life-threatening situations, time seems to slow down. He remembers the feeling clearly, he says. His body stumbles forward as the tar paper tears free at his feet. His hands stretch toward the ledge, but it’s out of reach. The brick floor floats upward—some shiny nails are scattered across it—as his body rotates weightlessly above the ground. It’s a moment of absolute calm and eerie mental acuity. But the thing he remembers best is the thought that struck him in midair: this must be how Alice felt when she was tumbling down the rabbit hole."
Eagleman is 39 years old now and an assistant professor of neuroscience at Baylor College of Medicine, in Houston. Excerpt.
"If Eagleman’s body bears no marks of his childhood accident, his mind has been deeply imprinted by it. He is a man obsessed by time. As the head of a lab at Baylor, Eagleman has spent the past decade tracing the neural and psychological circuitry of the brain’s biological clocks."
And this is how he spends his life - figuring it out for the rest of us. Excerpt.
"Although Eagleman and his students study timing in the brain, their own sense of time tends to be somewhat unreliable. Eagleman wears a Russian wristwatch to work every morning, though it’s been broken for months. “The other day, I was in the lab,” he told me, “and I said to Daisy, who sits in the corner, ‘Hey, what time is it?’ And she said, ‘I don’t know. My watch is broken.’ It turns out that we’re all wearing broken watches.” Scientists are often drawn to things that bedevil them, he said. “I know one lab that studies nicotine receptors and all the scientists are smokers, and another lab that studies impulse control and they’re all overweight.” But Eagleman’s ambivalence goes deeper. Clocks offer at best a convenient fiction, he says. They imply that time ticks steadily, predictably forward, when our experience shows that it often does the opposite: it stretches and compresses, skips a beat and doubles back.
The brain is a remarkably capable chronometer for most purposes. It can track seconds, minutes, days, and weeks, set off alarms in the morning, at bedtime, on birthdays and anniversaries. Timing is so essential to our survival that it may be the most finely tuned of our senses."
So, we all have some sense of time, but it is "intrinsically subjective." Which may explain why one of my sisters will always be late no matter how early she starts out. The biggest question: where and how does time exist? Apparently, time does not match reality. And this data led Eagleman to research:
"Why does time slow down when we fear for our lives? Does the brain shift gears for a few suspended seconds and perceive the world at half speed, or is some other mechanism at work?"
It seems that the only way to find out was to re-create situations in controlled settings. This leads to the amusement park ride and human subjects. "He needed something completely safe yet plausibly deadly. “I really chewed on this for a while,” he told me. “I couldn’t put people in a car accident.” Then he heard about the SCAD."
I am going to jump ahead here because I am fascinated with just how complex we human creatures really are. Folks try to dissect us this way and that way into isolated brain parts but the bottom line is a lot is not clear. Excerpt.
"Just how many clocks we contain still isn’t clear. The most recent neuroscience papers make the brain sound like a Victorian attic, full of odd, vaguely labelled objects ticking away in every corner. The circadian clock, which tracks the cycle of day and night, lurks in the suprachiasmatic nucleus, in the hypothalamus. The cerebellum, which governs muscle movements, may control timing on the order of a few seconds or minutes. The basal ganglia and various parts of the cortex have all been nominated as timekeepers, though there’s some disagreement on the details. The standard model, proposed by the late Columbia psychologist John Gibbon in the nineteen-seventies, holds that the brain has “pacemaker” neurons that release steady pulses of neurotransmitters. More recently, at Duke, the neuroscientist Warren Meck has suggested that timing is governed by groups of neurons that oscillate at different frequencies. At U.C.L.A., Dean Buonomano believes that areas throughout the brain function as clocks, their tissue ticking with neural networks that change in predictable patterns. “Imagine a skyscraper at night,” he told me. “Some people on the top floor work till midnight, while some on the lower floors may go to bed early. If you studied the patterns long enough, you could tell the time just by looking at which lights are on.”
“There’s always an impulse toward phrenology in neuroscience—toward saying, ‘Here is the spot where it’s happening,’ ” Eagleman told me. “But the interesting thing about time is that there is no spot. It’s a distributed property. It’s metasensory; it rides on top of all the others.”
The real mystery is how all this is coördinated. When you watch a ballgame or bite into a hot dog, your senses are in perfect synch: they see and hear, touch and taste the same thing at the same moment. Yet they operate at fundamentally different speeds, with different inputs. Sound travels more slowly than light, and aromas and tastes more slowly still. Even if the signals reached your brain at the same time, they would get processed at different rates. The reason that a hundred-metre dash starts with a pistol shot rather than a burst of light, Eagleman pointed out, is that the body reacts much more quickly to sound. Our ears and auditory cortex can process a signal forty milliseconds faster than our eyes and visual cortex—more than making up for the speed of light. It’s another vestige, perhaps, of our days in the jungle, when we’d hear the tiger long before we’d see it."
Before I leave you to delve further into Eagleman's work, two mentions: (1) he fell under the spell of Francis Crick, the biologist who years earlier had won the Noble Prize with James Watson for deciphering the structure of DNA. Crick called the work of inquiring into the notion of individual awareness "the scientific search for the soul." And (2):
"Something similar happens in language all the time, Dean Buonomano told me. If someone says, “The mouse on the desk is broken,” your mind calls forth a different image than if you hear, “The mouse on the desk is eating cheese.” Your brain registers the word “mouse,” waits for its context, and only then goes back to visualize it. But language leaves time for second thoughts. The flash-lag effect seems instantaneous. It’s as if the word “mouse” were changed to “track pad” before you even heard it.
The explanation for this is both simple and profoundly strange."
And now for the rest you're on your own. No storyteller worth her salt would ever reveal the end too soon or tell the listener what the moral of a story is - it's your own discovery.
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