Minimum distance error <i>D-min</i> continually decreased in groups receiving error amplification.

<p>Panel <b>A</b> shows the raw <i>D-min</i> for an exemplar subject in the DEA-2.0 group; black hollow circles are the actual errors; the red circles are the amplified errors. Panels <b>B</b> to <b>D</b> show <i>D-min</i> for the last day of practice with no manipulation (Day 3) and three subsequent days (Day 4–6) in which subjects received either no error amplification (controls; panel <b>B</b>) or different magnitudes of deterministic or stochastic error amplification (DEA or SEA, respectively; panels <b>C</b> and <b>D</b>). For panels <b>B-D,</b> <i>D-min</i> was averaged in 20-trial bins. The insets in each plot show the averaged data for all six practice days.