Have you ever felt time moving faster or slower than usual? For most of us, there is one obvious example of this, and we describe it with the phrase “time flies when you’re having fun”. You probably first noticed this effect back at school: in a boring class, time would pass slowly enough to drive you insane, but out in the playground, 1 hour lunch breaks would feel more like 20 minutes. It’s another grand injustice to add to the human condition, like the fact that the best-tasting foods are the most likely to kill you.
Scientific experiments have indeed shown that even under controlled conditions in a lab, we actually perceive time to be significantly shorter when we are enjoying ourselves. In fact, we may even use our time perception as a cue to judge how much we enjoyed an event: the less time it seemed to take, the more fun it must have been. Like many seeming injustices in nature, there are often good evolutionary reasons for the annoying things in our lives.
So what reason could there be for time passing faster when we are positively motivated? One strong theory is that when things are fun, they are likely to be important and so we should spend more time on them. Eating, playing, and sex are all critical drives, so they need to be fun in order to motivate us to chase them down. And if time is moving faster while we engage in these important tasks, we are likely to spend a lot more time on them before moving on to do something else. Fortunately, in the modern developed world, we’ve crafted environments that make it incredibly easy to fulfill these fun drives. Most of us only need to travel for a few minutes to get our hamburger hit. Unfortunately, when it’s so easy to find high-calorie food, it’s also easy to eat ourselves into an unhealthy lifestyle.
We’ve commonly experienced time moving faster during fun, but other time perception effects are more surprising. Find a ticking clock and stare at the ticking hand (a digital clock should be fine if you can see the seconds changing, ideally without the millisecond counter). Keep your head still as you look at the clock, and shift your eyes away from the clock as far to the left or right as possible without discomfort. Keep your eyes here for a short while, then shift your eyes straight back to fixate directly on the clock. Try it a few times so that you can manage this in a single eye movement.
When you look back to the clock, you may notice the ticking hand freeze for a moment. Time noticeably slows down during that single second. This effect is called chronostasis. When you shift your eyes (saccade), the world becomes a complete blur, because the image on your retina is violently moving around. And yet, despite these fast and very frequent saccades, you never feel disoriented or even surprised. This is because your marvelous brain automatically suppresses vision during each saccade to make life a little less dizzy. When you finish a saccade, the brain needs to compensate for lost time. It replaces the vision you lost during the saccade with the new image you see in front of you. So time feels momentarily slower, because your perception is packed with a bit extra. The brain is so good at this that you rarely notice it happening, but when you have a reliable external indicator of time, like a ticking clock, it’s much easier to see the effect in action.
Other interesting reports of time slowing down come from experienced athletes. For example, tennis and baseball players explain that as the ball approaches them, it appears to slow down allowing them to see it more clearly as they prepare to strike — you might think of this as feeling ‘in the zone’. A few years ago, my colleagues at UCL found that when people prepare a reaching action with their arm, time slows and their vision actually improves as the brain takes in more information. Expert basketball players also appear to mentally experience the actions of other players in slow motion.
This is all great evidence that our brains manipulate time when we need a little extra help. It’s always exciting to be reminded that our brains are not passive narraters of the reality around us. They are instead active reconstructors that have evolved to interpret the world in a way that is efficient and practical for survival.