Have you ever dropped something, only to watch in slow motion as it falls and breaks?
Humans and other animals are good at estimating short time durations, which has led psychologists to infer that we must have some kind of internal clock. One influential theory for how this clock works is that it’s like a pacemaker that releases pulses. These pulses gather in an ‘accumulator’ and give us a sense of how much time has passed.
But as you say, our internal clock is far from perfect, with many factors affecting how it works and distorting our subjective sense of time. A popular explanation is that this happens via the speeding up or slowing down the release of pulses from the pacemaker.
Let’s take your example of falling, an experience that most people find scary. Research suggests that when we’re scared, the pacemaker goes into overdrive and releases pulses more quickly. This leads to more pulses in the accumulator and an overestimation of how much time has passed.
Say you fell for five seconds – if your accumulator filled up more quickly than usual, you might judge that seven seconds had gone by. In other words, time would appear to have stretched, to be longer than it really is, which you perceive as the passage of time having slowed down.
Scientists have mimicked these effects with drugs. Stimulants that increase arousal lead to overestimates of the passage of time (felt as time slowing down), while drugs, such as tranquillisers, that lower arousal, tend to lead to underestimates of how much time has passed (felt as time speeding up).
You may have noticed that in action movies, the hero will often experience time as slowed down during a dramatic event and this gives them a kind of super sense for what’s going on. That would be cool if it were true, but sadly a study from 2007 suggested that that’s not how it works. They tested volunteers’ ability to perceive a rapidly moving image as they fell onto a safety net. The volunteers felt like time had slowed down, but it didn’t help them perceive the dynamic image.
Read more:
- Why does time seem to go slower when we’re bored?
- How does time change when we dream?
- Why does time speed up when you get older?
- Do dogs have a concept of time?
Asked by: Kacie Wong, Peterborough
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