Attempting to understand why people seem to experience time dilation during frightful situations like falls and accidents, scientists at Baylor College of Medicine in Houston, Texas developed a simple watch-like device dubbed the “perceptual chronometer”. The results seem to deflate the time inflation dogma:
“People commonly report that time seemed to move in slow motion during a car accident,” said Dr. David Eagleman, assistant professor of neuroscience and psychiatry and behavioral sciences at BCM. “Does the experience of slow motion really happen, or does it only seem to have happened in retrospect? The answer is critical for understanding how time is represented in the brain.”
When roller coasters and other scary amusement park rides did not cause enough fear to make “time slow down,” Eagleman and his graduate students Chess Stetson and Matthew Fiesta sought out something even more frightening. They hit upon Suspended Catch Air Device diving, a controlled free-fall system in which “divers” are dropped backwards off a platform 150 feet up and land safely in a net. Divers are not attached to ropes and reach 70 miles per hour during the three-second fall.
“It’s the scariest thing I have ever done,” said Eagleman. “I knew it was perfectly safe, and I also knew that it would be the perfect way to make people feel as though an event took much longer than it actually did.”
The experiment consisted of two parts. In one, the researchers asked participants to reproduce with a stopwatch how long it took someone else to fall, and then how long their own fall seemed to have lasted. In general, people estimated that their own fall appeared 36 percent longer than that of their compatriots.
However, to determine whether that distortion meant they could actually see more events happening in time – like a camera in slow motion – Eagleman and his students developed a special device called the perceptual chronometer that was strapped to the volunteers’ wrists. Numbers flickered on the screen of the watch-like unit. The scientists adjusted the speed at which the numbers flickered until it was too fast for the divers to see.
They theorized that if time perception really slowed, the flickering numbers would appear slow enough for the divers to easily read while in free-fall.
They found that while the subjects were able to read numbers presented at normal speeds during the free-fall, they could not read them at faster-than-normal speeds.
More from BCM press release: Does time slow in a crisis?
Complete article at PLoS ONE: The Effect of Predictability on Subjective Duration