“If I received 10 cents each time my child says ‘are we there soon?’, I would already be rich”: this is what many parents can say to themselves when undertaking family trip. Having three young children myself, I know all too well the fear that can take hold of you when, barely 30 minutes after the start of a trip that should last five hours, the interrogation begins.

It all starts out rather politely. “Mom, when are we getting there?” a small voice calls out from the back seat of the car. Then the tone becomes more offensive and we begin to compare the distance that I had announced an hour earlier and the one that still remains to be covered…

When the trip ends, I’ve usually resolved never to go on vacation with the kids again. But why do the journeys seem so excruciatingly long to them?

Perception of distances

One explanation is that our experience of time changes with age , often resulting in the feeling that time passes more quickly as we get older. This will give the impression that “Christmas comes faster every year”.

It is assumed that this impression of time passing more quickly comes from the fact that with age, each duration becomes a smaller proportion of our life. At age 7, for example, one year represents 14.30% of your entire life. At age 70, that’s only 1.43% of your life. Thus, a five-hour trip seems far more impressive to a 5-year-old than to a 50-year-old, simply because it equates to a longer portion of his life.

But there are other things to consider. As we grow up, as we get older, we understand what relates to distances and geography. This wealth of knowledge helps us find benchmarks and clues to assess where we are on a journey and the journey that remains to be covered.

For example, if I go from Paris to Amiens, I know that we enter the final stretch of the trip when we pass Beauvais. In the UK, if I’m going from Manchester to Devon, I know I’m about halfway when we leave Birmingham. This information helps me structure the time. I also have a GPS that gives me an arrival time, adjusting it in real time, warning me of obstacles and possible delays. Without direct access to these facts, children depend on what adults tell them to estimate the progress of the journey.

Attention span

The uncertainties children face are heightened by the lack of control they have over the journey itself. Adults determine which gas station to stop at and which route to take, which can make them feel like the journey is dragging on.

Indeed, time uncertainty , or the feeling of not knowing when something is going to happen can slow down the passage of time, and this is a phenomenon that we also experience in adulthood.

Remember the last time your train inexplicably stopped just outside the station, or you saw the “waiting” sign endlessly flashing in front of baggage claim as you exited the plane. I bet none of these issues were resolved quickly in your eyes – and you would have appreciated an announcement from the train conductor or airport staff. Not knowing what is going on gives us the impression that events are dragging on.

As soon as a doubt about a deadline appears, controlling it will quickly become our primary objective. Human beings have a limited cognitive capacity and cannot pay attention to everything all the time. We must therefore set priorities according to the circumstances.

When a deadline becomes uncertain, we pay much more attention to it than normal, which results in the feeling that time passes much more slowly. Since children are more subject to these uncertainties than adults, without distraction, they will scrutinize the progress of the journey, whatever it may be.

Boredom and entertainment

Finally, if the time spent in the car can go on forever for children, it is quite simply because they are locked up and have nothing else to do but watch the landscape pass by through the window. This experience confronts them with boredom while their parents, up front, probably relish having some time to sit and think.

Children’s desire for stimulation and entertainment often causes this boredom to set in quickly, slowing the passage of time. Like temporal uncertainty, our level of boredom affects our perception of durations by modifying the attention we pay to it.

In these cases, we tend to scan the clock, which gives us the impression that time is stretching out . Conversely, when we’re happily busy, we pay little attention to the time, our attention span being taken up by other things, and we feel like time flies .

So what should parents do? Those of you with a big trip in store might be rushing to stock up on games and snacks to provide a steady stream of entertainment for your kids. However, I urge you to be careful. If you manage to reduce the refrain “are we there soon? “, perhaps you wake up there the risk of another catchphrase:” My heart hurts! And when a child gets motion sickness, both experience and research show that it’s up to the parents that the journey is going to seem much longer

Author Bio: Ruth Ogden is a Reader in Experimental Psychology at Liverpool John Moores University