Why the trip home is shorter, but not faster
When we travel by car the trip home often seems shorter than the initial trip away from the place of origin. This perceptual phenomenon (called the Return Trip Effect) has been noted in many contexts and its existence has puzzled drivers and researchers alike since the distance travelled and time spent traveling are usually identical. It has recently been proposed that the reason for this effect may be due to the fact that the outward trip has more unpredictable elements which make the initial trip seem longer. An alternative interpretation is that drivers pay less attention to familiar tasks (like the trip home) and our sense of trip duration is shorter when we are engaged in task-unrelated thoughts. In this paper we provide data from a driving simulator experiment that contrast these two interpretations as well as determine actual travel times as drivers complete return trips on familiar roads. The results indicate that there is no difference in participants' travel times on the two legs of the journey (i.e., the return trip is not actually faster). When elements of the scene are changed to include new elements and change existing elements during the return leg, the participants' actually did travel faster (decreasing their return trip time). Although changing expectations may play a role in the Return Trip Effect for unfamiliar destinations, when traveling on familiar roads these data suggest that lower levels of conscious engagement with driving is the likely reason for the subjective experience of shorter return trips.