Scientists discover the 'return trip effect' is only felt retrospectively

A team of scientists at Kyoto University discover that homeward bound trips feel shorter than outward bound trips, but only after the trip is complete.

Science Notebook

Have you ever noticed that the trip home feels shorter than the trip out?

You're not alone. A number of previous studies have attempted to test this phenomena, known as the “return trip effect,” but none has been able to confirm its existence in the real world. Previous studies, say critics, used trips of durations that were unrealistically short or through environments not found in real life.

But now, research undertaken by Ryosuke Ozawa of Kyoto University, along with colleagues across Japan, suggests that the return trip effect is felt only retrospectively. Their findings appear in this week's issue of the scientific journal PLOS ONE.

In this experiment, 20 males were shown movies, filmed by the research team, of a figure walking. The three groups each watched either an outbound trip and a return trip or two outbound trips.

The subjects were then quizzed, using both prospective and retrospective timing methods. Prospective timing was assessed by having the participants indicate when they believed 3 minute intervals occurred, which tested temporal perception in real time. Retrospective perception, assessed after the movie ended, was measured on an 11-point scale, ranging from shortest to longest. In reality, all movies were equally long, clocking in at just over 20 minutes.

Those marking three-minute intervals during the movie showed no sign of displaying the return trip effect. But according to the 11-point scale results, only the groups that watched the “round-trip” movies estimated that the return trip was shorter.

Prior research conducted by Dan Zakay in 2012 found that the more you need to be at an important event at a specific time tend, the longer the trip there will feel. This happens, Dr. Zakay argued, because you devote more mental resources to thinking about the trip. But on the way back home, the time is no longer as important and fewer resources are devoted to it, making the trip seem shorter.

Now Ozawa’s latest research indicates that we do indeed experience this phenomena, but only after the fact.