Abstract
When participants are presented with a target and overlapping penalty region, participants initially aim closer to the penalty region than optimal before shifting their endpoint to a more optimal location. Previously we divided participants into three groups, to explore the effect of different types of visual feedback. In the No Feedback group, the target/penalty configuration would disappear when participants initiated the movement. In the Terminal Feedback group, the configuration would disappear and then reappear upon screen contact. Finally, a Full Feedback group saw the configuration for the entire duration of the movement. We showed no difference in endpoint adaptation away from the penalty region over the course of exposure between the groups, but the Terminal/Full Feedback groups showed greater undershooting of the target, even once full feedback was given in a transfer task. Our results may be related to the finding that individuals have two distinct phases of movement: an initial increase in velocity to reach peak, followed by a decrease presumably to fine-tune the movement using visual feedback. The purpose of this study was to compare the kinematics of the reaches made to the target/penalty configurations under different feedback conditions to determine how visual feedback may have impacted endpoint selection. Results indicate that movement kinematics, including time after peak velocity, changed across exposure to the task in all groups. Other feedback mechanisms, aside from visual feedback, may have helped participants in all conditions select a more optimal endpoint over the course of task exposure.
