Abstract

Sensorimotor synchronization is the process by which we are able to synchronize a motor response with a sensory stimulus that occurs at predictable intervals over time. A common experimental paradigm for studying this process is finger tapping to a metronome. It has been found that finger trajectory is asymmetric and this asymmetry increases with timing accuracy, suggesting that the relatively high velocity of the finger flexion phase compared to the extension phase may provide proprioceptive feedback that aids in synchronization. In this study, we examined how the kinematics of the motor response varies in relation to changes in the frequency of occurrence of the stimulus and to changes in the degree of sensory feedback during the motor response. Participants were asked to tap on three different surfaces offering varying degrees of tactile feedback while synchronizing to a virtual metronome playing at one of two different rates. Motion capture equipment recorded their finger movement. It was expected that the greater the amount of sensory feedback from the tapping surface, the more symmetric the finger trajectory would become, as dependence on a high velocity phase could decrease and movement could more resemble the symmetric sinusoidal motion that models of motor control would predict for the repetitive to and fro movement of finger tapping in the absence of a synchronization constraint. We provide evidence showing that the degree of tactile feedback from the tapping surface does influence trajectory and velocity.