Judging joint angles and movement outcome: Shifting the focus of attention in dart-throwing.

Many research studies have shown the advantage of an external focus of attention (FOA) relative to an internal focus for motor learning and performance when the focus is explicitly instructed. The current experiments varied the FOA by asking the participants to judge either joint angles (internal probes) or spatial accuracy (external probes) following dart throws in which vision was removed. The probes were administered without prior practice (Experiment 1) or following 432 practice trials (Experiment 2). Spatial errors and trial-to-trial variability were reduced in Experiment 2 compared with Experiment 1. In both experiments, spatial errors were greater during internal probes compared with external probes or a no-probe control condition. These data suggest that the advantages of an external FOA relative to an internal FOA are not fully attributable to visual processing and that these advantages can be attained using probing questions between trials, whereas previous research has explicitly instructed the FOA.