Eye movements are not a prerequisite for learning movement sequence timing through observation

The present experiment examined learning of a three-segment movement sequence using physical or observational practice, and whether permitting eye movements to be made during observation is a prerequisite for learning such a movement sequence. Specifically, participants were required to move a mouse cursor through a three-segment movement sequence in order to satisfy one of three movement time goals (800, 1000, 1200 ms). A yoked-participant design was used in which a physical practice group acted as a learning model, which was viewed simultaneously by two groups that carried out different observational practice procedures. An observation group was permitted to move their eyes whilst observing the model, whereas the fixation group was instructed to maintain fixation on a central target. The difference between pre-test and post-test data indicated that all the three experimental groups significantly altered their timing accuracy, variability and movement kinematics over practice, while the control group's behaviour was unchanged. These data indicate that movement time as well as the underlying movement control was learned following observation of a movement with or without an explicit contribution from eye movements, albeit to a lesser extent during the final segment of the sequence when compared to the physical practice group. The implication is that while similar processes might normally be involved in physical and observational practice, information afforded by eye movements during observation (e.g., efference copy and eye proprioception) is not necessary for movement sequence learning.