Timing the moment of impact in fast human movements.

The reported resolution of timing the moment of impact in fast human movements differs widely depending on the task. Surprisingly, better timing is reported for the demanding task of batting a ball than for the much simpler task of tapping in synchrony with two hands. We wondered whether this is because a sizeable part of timing variability arises from misjudging the distance in the direction of one's own movement, so that moving faster (as the bat does when moving toward a ball) improves timing. We found that moving faster does indeed improve timing in both the above-mentioned tasks. After removing the proposed contribution of misjudging the distance in the direction of one's own movement, we estimated that the remaining standard deviation in timing is just over 6ms for both tasks.