Entrainment

Processes of rhythmic coordination and synchronization, also known as "entrainment," are among the most disctinctive characteristics of human behavior. While recent research has shown that rhythmic entrainment is exhibited by non-human species from cockatoos to sea-lions, human entrainment is qualitatively different, however, because it involves:

• Flexibility and thus robustness of entrainment;
• Complexity of entrainable and entrained behaviors;
• High relevance for joint action and social interaction.

Currently, I am engaged in three projects dealing with synchronization and entrainment.

Nori Jacoby, Justin London, and I are studying two corpuses of jembe drum ensemble music from Mali, which together comprise approx. 4 hours of running time. We extracted the onset timings of all drum-strokes for each of the ensemble members, which amounts to a total of about 190,000 data-points. Our analysis asks who follows whom, and who adapts to whom, as revealed by the process of micro-rhythmic error correction that allows us keeping in time together.

In the second of the two corpuses, we had four different trio ensembles play the same piece over and over again (74 takes all told) and had the two jembe players in each ensemble switch roles between accompaniment and lead parts. We are thus able to tease apart the effect of a player's musical role (lead vs. accompanying drum) from their individual personalities in the entrainment process.

The project is deeply collaborative, with workloads shared between Nori, Justin, and myself. To our knowledge, this is the first study of its kind outside the realm of European art music, in a field of research pioneered by studies in piano duet and string quartet playing.

Tapping along with simple rhythmic stimuli has been among the most influential experimental paradigms for the study of our rhythm perception and synchronization capacities. Many studies using Western participants gave robust evidence for a bias towards the simplest integer ratios (1:2 in particular) in synchronizing with uneven rhythms.

I designed and am coordinating a collaborative project that partially replicates, in cross-cultural setting, a classical experimental study by Dirk-Jan Povel (1981). Daniel Goldberg, Andre Holzapfel, Timo Fischinger, and I tested culturally diverse participant groups from four different countries on three continents. Nori Jacoby, Justin London and I will collaborate in analyzing data and the interpretation of results.

To our knowledge, this is among the first studies applying the tapping paradigm to understand rhythm perception in cross-cultural and cross-sub-cultural perspectives.

I am participating in an international research project on Interpersonal Entrainment in Music Performance, co-ordinated by Martin Clayton and Tuomas Eerola of Durham University. I have contributed a corpus of audio-visual recordings of jembe drum ensemble performances and will help design an experiment to study the perception of ensemble entrainment with and across cultural contexts. I then will carry out this experiment in Mali, in parallel with similar experiments carried out in other cultural contexts.

In the future, I hope to expand my perspective to include rhythmic co-ordination and entrainment in music and dance.