Benefits of blocked over serial feedback on complex motor skill learning

The effects of blocked versus serial feedback (FB) on the learning of a com plex motor skill-the production of slalom-type movements on a ski-simulator -were examined. FB was given about force onset, which is considered to be a measure of movement efficiency; relatively late force onsets characterize expert performance. One group of participants (blocked FB; n = 10) received FB about 1 foot per day; for example, for the right foot on Days 1 and 3 a nd for the left foot on Days 2 and 4. For another group (serial FB; n = 10) , the foot about which FB was received was switched on consecutive trials o n each of 4 days of practice. Learning was assessed on no-FB trials at the beginning of Days 2, 3, and 4, and on Day 5. Even though there were no diff erences between groups in force onset, the blocked FB group produced signif icantly larger movement amplitudes and higher movement frequencies than the serial FB group on the retention test on Day 5. Thus, contrary to the lear ning of more simple skills (e.g., T. D. Lee & H. Carnahan, 1990), constantl y changing the movement component that FB is provided about did not seem to be beneficial for the learning of more complex skills. The findings add to the increasing evidence showing that practice variables that have been sho wn to enhance the learning of simple skills can actually be detrimental to the learning of complex skills.