Résumé
We often move in synchrony with auditory rhythms such as while listening music, applauding or dancing with other people. The control of such coordination is one of the main issues in experimental psychology and several studies have investigated the processes underling the synchrony of our movements with a metronome (Repp, 2005). It has been demonstrated that the processes underlying the synchronization depend on whether the movement is continuous or discontinuous. More specifically, synchronized continuous and discontinuous movements present differences at the level of cycle-to-cycle dynamics. An event-based timing has been revealed in synchronization of discontinuous movements and an emergent timing in synchronization of continuous movements, which are characterized respectively by a negative or non-negative lag 1 autocorrelation of the series of movement's periods (Torre & Delignières, 2008). Continuous and discontinuous movements also present differences at the level of within-cycle dynamics. The limit cycle (velocity vs. position) of synchronized discontinuous movements has an important nonlinearity and asymmetry whereas the limit cycle of continuous movements is nearly circular with a slight asymmetry at the point where the metronome occurs (Torre & Balasubramaniam, 2009). It has been demonstrated that cycle-to-cycle and within-cycle dynamics are not independent and that the specific movement trajectories observed for continuous or discontinuous movements contribute to the achievement of emergent and event-based timings, respectively.