Each motif is a different combination of three different types of taps. In a long tap, the user keeps the finger on the trackpad for two beats. A short tap consists of a single beat, and a pulse tap is a quick tap on the touchpad. The researchers assume that each combination of taps would be carried out across a regular interval at about 120 BPM (beats per minute) though the speed of the interval could be easily changed to match the user's dexterity.

In their tests, the researchers had found that users could easily learn and reproduce this series of taps, and could then use these taps as shortcuts for commands. After the tests were completed, 9 of the 14 participants preferred using the rhythmic patterns over the hot keys, and another two had no preference.

The research could open a new form of user interface, noted Princeton University computer science assistant professor Rebecca Fiebrink, who moderated Ghomi's talk. People all over the world can naturally recognize and respond to rhythms. "Rhythm is something people have an innate ability to perform" yet it's not used as an input very often, she said, adding that someone does not need to be trained as a musician to easily learn the researchers' rhythmic motifs.

Ghomi did not estimate how many tap patterns a user could potential memorize, though he speculated that it would probably not be that much different than the total number of hot-key combinations users remember. He referred to earlier studies showing fluent computer users memorize about eight hot-key combinations.

The IDG News Service