Musical structure, micromotion, and adaptive gesture in instrumental performance: a critical cross-study synthesis

This article presents an integrative synthesis of seven studies conducted within a research program on expert saxophone performance: five performer-centered observational, kinematic, and interview studies, complemented by two perceptual experiments. The studies are compared according to musical and task conditions, movement descriptors and scales, and evidential perspective. Rhythm and pitch were most consistently associated with movement. Faster or rhythmically denser passages were linked to shorter or more frequent actions, while rhythmic density increased knee-cycle frequency as amplitude decreased. Pitch contour accompanied recurrent flexion–extension patterns, and knee trajectories showed predictive temporal precedence relative to a modeled pitch-expectation profile. Under movement restriction, projected center-of-mass range, velocity, distance, and area decreased, whereas knee phase changes increased and specific postural-frequency measures remained comparatively stable. Three non-exclusive interpretations of persistent micromotion are considered: postural regulation, sensorimotor entrainment and prediction, and motor learning. On this basis, the paper proposes an adaptive, multidimensional model in which musical structure and task constraints selectively reorganize movement across dimensions and scales, while expressive, technical, postural, and communicative functions remain overlapping and context-dependent. The model provides an empirically grounded framework for causal experiments and learning interventions on the functions of performative movement.