Fig. 1.

Schematics showing the proposed learning framework and task design. (A) Schematic showing how the forward model may support implicit motor adaptation in the presence of sensory FB not causally related to self-generated movement. (B) Events on trials with visual FB. The robotic apparatus brought the participant’s hand to the starting location to initiate a trial. On movement trials (Top), the target turned green (GO), cueing participants to reach through the target. On trials with visual FB, participants observed a white FB cursor move along a rotated trajectory (Rotation). On no-movement trials (Bottom), the target turned magenta 100 ms after turning green, cueing participants to withhold movement (STOP). After a delay, an animation played showing the FB cursor moving 15° off-target (Animation). The hand is shown in the figure for illustrative purposes but was not visible during the experiment. (C) How STL was computed using a triplet paradigm. Triplets were composed of two go trials without visual FB flanking either a movement or a no-movement trial with visual FB. STL was measured as the difference between reach angles on the flanking trials. (D) Pseudorandomized order in which trials were presented for an example participant. Color indicates movement condition (movement, green; no-movement, magenta).