How do conductors' movements communicate compositional features and interpretational intentions?

Conductors use body movements to communicate their interpretations of musical works though performance directions regarding selected musical features. The aim of this study was to examine how the kinematic features of conducting movements relate to compositional elements such as rhythmic patterns, melodic peaks, dynamic changes, and also how they relate to conductors’ own interpretational comments. Six conductors with conducting experience of between 4 and 29 years were interviewed and asked to annotate a musical score (Eine Kleine Nachtmusik by W. A. Mozart, No. 13, K. 525, first movement, mm. 1–55) according to a number of interpretational intentions. They then performed the same piece of music with a string quintet, while their upper body movements were recorded using a 9-camera Qualisys motion capture system. Kinematic parameters including baton speed, acceleration, and jerk were extracted via Visual 3D and Matlab software packages. Cross correlation confirmed that, as expected, within conductor baton movement kinematic patterns were more similar than between-conductor patterns. A novel analysis method (Deviation Point Analysis) was developed, which revealed particular time-points in the score with distinctive baton movement features, including movement kinematic deviations and high movement variability between conductors, which related to specific melodic, rhythmic, and dynamic
structures and interpretational intentions.