Fig. 4.

A: motor learning as reflected in lateral force production early in force field learning. Mean normalized force profiles (±SE) over the course of movement are shown. A value of 1 represents full compensation for the force field. B: lateral force production late in force field learning. Subjects in the reinforcement group show greatest learning; control subjects show least learning. Data for the 24-h condition are not shown but lie behind the passive group data. C: motor learning as evaluated by lateral forces applied to the channel walls, normalized by the ideal force, for movements early and late in learning (means ± SE). It can be seen that the force index increases from early to late in learning. *P < 0.05; **P < 0.001.