The ability to estimate short durations of time is critical for learning and survival, said Dr. John Gibbon of the New York State Psychiatric Institute and Columbia University. The human interval clock is running all the time as people unconsciously monitor the timing of external events and respond to them. Unconsciously, you are counting the seconds, without looking at your watch. But if the light fails to turn green in the expected amount of time, you start fretting, wondering if it is working properly. If enough time passes, you may decide to run the red light.
People use interval clocks when engaged in music or sports.
Basketball players, Meck points out, know that they will be penalized under certain circumstances if they hold the ball for longer than several seconds without dribbling or passing. They keep track of the time in their brains rather than by checking a clock. Musicians use their interval clocks to simultaneously measure not just the beat but the phrase, the crescendos and innuendoes. Great jazz players shade the time in violation of strict beats and that is what makes the music interesting, Gibbon said. In the case of the basketball player, different parts of the brain are working on different tasks.