Interlimb Coordination of Rhythm and Beat Performance

Interlimb coordination is critical to the successful performance of simple activities in everyday life and it depends on precisely timed perception-action coupling. This is particularly true in music-making, where performers often use body-movements to keep the beat while playing more complex rhythmic patterns. In the current study, we used a musical rhythmic paradigm of simultaneous rhythm/beat performance to examine how interlimb coordination between voice, hands and feet is influenced by the inherent hierarchical relationship between rhythm and beat. Sixty right-handed participants—musicians, amateur-musicians and non-musicians—performed three short rhythmic patterns while keeping the underlying beat, using 12 different combinations of voice, hands and feet. Results revealed a bodily hierarchy with five levels 1) left foot, 2) right foot, 3) left hand, 4) right hand, 5) voice, implying a more precise task execution when the rhythm was performed with a limb occupying a higher level in the hierarchy than the limb keeping the beat. The notion of a bodily hierarchy implies that the role assigned to the different limbs is key to successful interlimb coordination: the performance level of a specific limb combination differs considerably, depending on which limb holds the supporting role of the beat and which limb holds the conducting role of the rhythm. Although performance generally increased with expertise, the evidence of the hierarchy was consistent in all three expertise groups. The effects of expertise further highlight how perception influences action: Embracing a predictive coding view, we discuss the possibility that musicians’ more robust metrical prediction models make it easier for musicians to attenuate prediction errors than non-musicians. Overall, the study suggests a comprehensive bodily hierarchy, showing how interlimb coordination is influenced by hierarchical principles in both perception and action.