LEILA FADEL, HOST:
Here's something that new parents hear a lot, especially from older parents. The days are long, but the years are short. For the latest in our series Finding Time, NPR's Rhitu Chatterjee explores the science behind that old parenting adage.
RHITU CHATTERJEE, BYLINE: Almost as soon as our son was born, we started to hear this common saying from friends and family. I remember my mother-in-law telling us that we should try and enjoy every day, no matter how hard it might feel in the moment. Now, I was in my early 40s when I became a mom. Time already felt precious to me. And pregnancy complications had forced my son into the world six weeks before his due date. So I couldn't take any moment for granted. When we finally brought our tiny 4-pound, 9-ounce preemie home from intensive care, I was determined to enjoy every minute with him.
(SOUNDBITE OF BABY VOCALIZING)
CHATTERJEE: Hi, Shona. Look at Ma. Look at Ma.
I wanted to make precious memories like these, hoping that in the process I could slow time down. And I did succeed, but only for brief moments, like when our son flashes a smile at us or when he rolled over for the first time. But now that he's nearly 3 years old, I'm finding myself looking back and wondering where the time went.
SHONA: And then a tree man came.
CHATTERJEE: When did my baby turn into a toddler who speaks full sentences and makes up his own bedtime stories?
SHONA: Tree man was driving a tree truck. And it's full of trees in the tree truck.
CHATTERJEE: Wow. So a tree man came with the tree trunk.
So is there a biological explanation for the shared experience of parental time? And why is that even when we do succeed to slow time down in the moment, the years still fly by? To find out, I called Peter Tse, a neuroscientist at Dartmouth College.
PETER TSE: We don't have a single perception of time. We have perception of time in the moment. Perceptual time, you might call that. And then you have how you regard time by looking through your memories.
CHATTERJEE: Let's start with our perception of time in the moment.
TSE: We don't have a cesium atom clock in our head that's saying, OK, this how many units of objective time have gone by.
CHATTERJEE: Rather than a super-precise timekeeper, he says the brain uses the amount of information it processes in the moment.
TSE: So if you process more information per unit objective time, time seems to slow down.
CHATTERJEE: Like when you're visiting a new place, soaking in all the details of the sights and sounds around you or during an emotionally charged incident.
TSE: For example, if you're driving and you're skidding and about to hit the back of a car, it seems to go in slow motion. Because suddenly your brain's processing tons of information and you're fully attentive, time seems to slow down.
CHATTERJEE: It's the same when a parent has those emotionally engaging moments with their child. Psychologist Ruth Ogden is at Liverpool John Moores University.
RUTH OGDEN: The things that you're talking about, like your child first rolling over, your child first talking to you about something that you think is important, when you have those meaningful conversations with them, even when they're about nothing.
CHATTERJEE: Ogden studies how our perception of time changes with different experiences, and she's also a mother of three.
OGDEN: Specifically in these two-way interactions that we have with our children, they are very all-encompassing for us. They are joyful moments, like you said. It's something that you treasure forever. And that means when you're in them, you're not thinking about anything else.
CHATTERJEE: And so they last longer in the moment. It's also why we have such vivid memories of these experiences. But if parenthood is full of these beautiful memory-making moments, why then do our kids' childhoods seem to go by so quickly? Ogden says that has to do with the less-fun part of parenting.
OGDEN: Parenting is full of routine. It's full of organization. It's full of - for want of a better word, there's a lot of monotony in parenting.
CHATTERJEE: Consider caring for a newborn. We spend most of our time indoors trying to make sure the baby eats, poops, naps and sleeps on time - tedious and monotonous tasks that can make the days drag on and bleed into one another but in the end aren't very memorable at all.
OGDEN: So when you're trying to make a routine, you don't do anything new. And that kind of means that you don't form as many memories as you would normally do.
CHATTERJEE: And the number of memories, Ogden says, is key to how the brain estimates time in retrospect.
OGDEN: To help us to judge how long or short something was. Our brain looks at how many memories we formed in a period of time.
CHATTERJEE: If there are lots of memories...
OGDEN: Then it must have been a long time, and if I've got very few memories from that time, it must have been a short time.
CHATTERJEE: But Ogden says there's a way to counteract this by focusing less on routine and more on ways to make new memories with our kids.
OGDEN: The more you break the out with different activities or different things today, then the more chance you've got of making these nice memories, the things that are going help to stretch out your retrospective feelings on how the years passed when your children were young.
CHATTERJEE: And that's what happened with our family last year. Recently, while driving back home from somewhere, my husband Nick and I realized that 2022 had felt longer than the two years before.
NICK: Yeah. We were able to travel more and see more friends and loved ones.
CHATTERJEE: Like, we went to New York. We went to South Carolina.
NICK: We introduced him to dolphins in Florida.
CHATTERJEE: And we went to India, where our son finally met my uncles, first cousins, second cousins. We celebrated an Indian festival, Durga Puja, introduced him to the sounds and smells that make up so many of my childhood memories.
(SOUNDBITE OF MUSIC)
CHATTERJEE: Last year was also the first time my father, who lives in India, was able to visit us for an extended period of time, giving us a whole new set of memories to cherish, like one summer morning when I woke up and found my father and my son snuggling and being silly together.
(SOUNDBITE OF ARCHIVED RECORDING)
UNIDENTIFIED PERSON: Goo, goo, goo, goo, goo.
(SOUNDBITE OF BABY LAUGHING)
CHATTERJEE: And perhaps sharing these memories more often is another way to remind myself that my son's childhood isn't going by in the blink of an eye.
(SOUNDBITE OF ARCHIVED RECORDING)
UNIDENTIFIED PERSON: (Non-English language spoken).
(SOUNDBITE OF BABY BABBLING)
CHATTERJEE: Rhitu Chatterjee, NPR News.
(SOUNDBITE OF MEN I TRUST'S "TAILWHIP REVISITED")
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