Gamelan Project Demonstration: Online Analysis of Synchrony

• In Event: Translating Scientific and Technological Advances From the Laboratory to the Classroom: It’s About Time

Abstract

The gamelan project is focused on the relationship between ability at synchrony, or the coordinated processing of time, and other cognitive abilities, especially those relating to attention and learning. An immediate challenge in undertaking such a study is that of recording and measuring group activity and interaction in an environment that reflects a normal classroom setting as fully as possible.

We constructed gamelan-like instruments such that each key (resonating metal plate) of each instrument was wired with piezoelectric sensors in such a way that its audio signal was perfectly isolated, allowing for very accurate recording and measurement of sound onsets, which correspond to subjects striking the keys. We analyzed each subject’s recording for vector strength, a measure that is often used in analysis of synchrony of neuronal firing.

Playing music in a group setting makes specific cognitive demands on players. The player must calculate rhythmic intervals and periods as played by the ensemble. Further, the player must be able to perceive the degree to which s/he was able to play successfully on the beat and calculate the difference into their next estimation so as to maintain a steady rhythm and remain synchronized with the ensemble. Finally, players must be able to listen selectively to various members of the ensemble, identifying which players or instruments must be “tuned in” and which must be “tuned out” in order to remain synchronized with the ensemble.

For the present demonstration, we will invite conference participants to play these instruments, and learn a few basic techniques from Alexander Khalil. An overhead on-screen display will show in real time how well each participant is synchronizing with the driving beat of the ensemble. Thus, participants as well as the audience in general will be able to experience the type of effort and processing needed to maintain synchrony while receiving real-time feedback from our online analysis.

Author

• Victor Minces, University of California - San Diego