The Role of Execution Noise in Movement Variability

摘要: The origin of variability in goal-directed movements is not well understood. Variability can originate from several neural processes such as target localization, movement planning, and execution. Here we examine resulting noise In experiments, subjects moved their unseen hand to visual targets, under conditions which were designed minimize the expected localization planning processes. We tested short 32 directions a center-out reaching task. endpoints initial direction varied systematically with direction, some having up twice others. second experiment four same but different extents. Here, longer curved, endpoint ellipses aligned straight line between starting end position, they roughly last part trajectory. show that observed these experiments cannot be explained by A combination both signal-dependent signal-independent amplitude motor commands temporal duration explain variability. Our results suggest that, general, execution accounts for at least large proportion