In children, a sense of time starts early

toddler holding alarm clock

As they grow, children develop a more sophisticated understanding of time.

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Young children are creatures of the here and now. It’s amazing to watch a moment of complete and utter devastation blow over as soon as the funny moose toy starts squeaking. These short attention spans are refreshing — there’s nothing like a toddler to encourage living in the moment.

But as they grow up, children expand their mental horizons to include the past and the future. Minutes, hours, days and years start to take on new meaning as children acquire a deeper concept of time.  

This gradual emergence is really fun to watch. Baby V, who isn’t a baby anymore, now understands the past. Her toddler brain categorizes anything that’s already happened as yesterday. She devoured a fancy ice cream sundae “yesterday,” even though that memorable event was weeks ago. Her concept of the future seems nebulous too, though I haven’t been able to test this precisely. We’re working with a slight language barrier.

At her tender age, Baby V already understands which way the arrow of time is pointing (though if you ask my physics-minded colleague Andrew Grant, we should be careful with those existential assumptions). After 2 1/2 years in this world, Baby V has picked out important patterns about time’s passage. But it turns out that she’s been doing this her entire life, studies suggest.

Babies are born into the world primed to sense time’s passing. If you think about it, most of what’s relevant to a baby’s life — milk, daylight, snuggles right before bed — come at somewhat predictable times. And babies are no dummies. They slurp up these patterns and use them to guess what’s coming next.

One of the clearest examples of this early sense of time comes from a study that put 1-month-old babies in the dark. Every 20 seconds, a light came on for four seconds, causing the babies’ pupils to shrink. After learning the pattern, the babies’ eyes started anticipating the light: Their pupils shrank every 20 seconds, even when the light didn’t come on, scientists reported in 1972.

Babies can even estimate durations, researchers have found. After watching a puppet of Sylvester the Cat jiggle while a tone played for certain lengths of time, 6-month-olds became bored and began looking at the puppet for less time. But when the tone unexpectedly lasted longer, the babies became interested again and looked longer, suggesting that the babies recognized the change in duration of the tone.

These results and others serve as evidence that babies actually possess a “primitive” sense of time that improves and grows more sophisticated with age, French psychologist Sylvie Droit-Volet describes in a 2013 review in Neuropsychologia.

Then, between the ages of 3 and 5, children grow more aware of time and its passing, particularly for mundane, everyday activities. But preschoolers still make some interesting perceptual errors, such as thinking that lights that shine brighter last longer, Droit-Volet writes.

Around seven, kids start to show signs of a sophisticated sense of time that Droit-Volet calls “explicit time knowledge,” exhibiting skills such as overtly estimating how long things will take. Children’s sense of time grows stronger from there. 

It’s fun to contrast children’s perceptions of time with my own as a parent. After reporting on how the brain cobbles together its own sense of time, I’m convinced that we all constantly fall prey to various timing mistakes. But I think parents, especially those with little kids, often experience time in strange ways. Since the arrival of Baby V and her little sister, I’ve definitely been tumbling through my own baffling time warp. It’s true, what they say. The days with young children are long, but oh, how the years are short.

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Laura Sanders is the neuroscience writer. She holds a Ph.D. in molecular biology from the University of Southern California.