When sitting in a classroom, boardroom, or doctor's office time seems to pass in slow motion. Yet when participating in activities you love, you can get so caught up that you completely lose track of time. New research may support the saying "time flies when we're having fun," is true, but more specifically time flies when we're having goal-motivated fun.

Prior research has suggested that when an individual is experiencing positive feelings, it makes one feel like time is passing at a faster pace. However, these feelings are not high in what experts call "approach motivation." Having fun alone, does not inspire one to want to go out and pursue or achieve a goal. On the contrary, feelings of desire or excitement are very high in approach motivation.

Philip Gable and Bryan Pool, psychological scientists of the University of Alabama, theorized that activities that are high in approach motivation are what make us feel like time is passing faster than normal.

To test their theory, they conducted experiments where participants were instructed to tell the difference between pictures shown for a short period of time versus a long period of time. They were also shown neutral images that were either positive but low in approach motivation (flowers) or positive and high in approach motivation (desserts). For each image they had to specify whether it had been displayed for a short or long period of time.

Results confirmed the researcher's theory. Participants perceived the images that were high in approach motivation as being displayed for a short amount of time.

In another study participants reported time passing faster when observing dessert images with the anticipation that they would be able to eat those desserts later.

Both studies confirm the feeling that time is passing quickly has to do with the yearning to approach or pursue something and is not based on fun or physiological arousal.

"Although we tend to believe that time flies when we're having a good time, these studies indicate what it is about the enjoyable time that causes it to go by more quickly," Gable said. "It seems to be the goal pursuit or achievement-directed action we're engaged in that matters. Just being content or satisfied may not make time fly, but being excited or actively pursuing a desired object can."

The study was published in the journal Psychological Science.