FIG. 5.

Human trajectories for the condition with resisting perturbation: (a) Early trial: in this trial, the subject dropped the ball from the cup, hence the trajectory ends just after $P^{+}$. (b) Late trial: the subsequent trajectory after the perturbation entered a contraction region. The black arrowhead indicates the starting point of the trajectory. $P^{-}$ denotes the instant just before the perturbation, while $P^{+}$ denotes the instant after the perturbation. The exact ellipse indicates that the cup has reached the target box at rest, while the pendulum was still oscillating.