Effect of imposed auditory rhythms on human interlimb coordination

A non-locomotor task was used to investigate human upper and lower extremity movement coordination. Eighteen normal adult subjects performed simultaneous clapping and foot-tapping in the seated position. Subjects performed the task at their preferred rate as well as at metronome rates of 1-4Hz. Temporal data and interlimb phase-linkage were analysed. Results of the temporal data indicated a reciprocal interaction among the upper and lower extremities. Most subjects also showed shifts in interlimb phase-linkage when they moved their limbs at metronome rates of higher than 1 Hz. These findings may suggest that the central nervous system (CNS) coordinates the self-paced movement of the extremities in the same way that it coordinates them under an externally-paced condition at slower rates.