Changes in learned motor behavior due to the effects of various forms of augmented kinematic feedback
Creators: name: Hale, Trevor A.
Publisher: name: University of British Columbia
Year: 2009

description: The present study was conducted to determine the relative effectiveness of four types of augmented feedback on the acquisition of a rapid aiming movement. Static graphic feedback depicting the primary submovement and error correction phases of the just performed movement (Static group) was compared to numeric KR (KR group). In addition, concurrent kinematic feedback (CD group) was compared to delayed kinematic feedback (DD group). It was predicted that delaying kinematic information would facilitate the performance of the DD group during no-KR retention trials, due to an increased processing of kinesthetic feedback during the movement and subsequent calibration of this information with the delayed visual feedback. It was found that participants in the CD group produced less absolute error, consumed a smaller proportion of TMT in the primary submovement phase, produced less variable primary submovement, and produced longer secondary submovements than participants in the other three groups. In addition they had significantly more trials containing an error correction phase than participants in the Static and DD groups. However, there was no statistical difference between the four groups in their overall Score, TMT, or constant error. These results indicated that participants in the CD group utilized a two movement strategy during Acquisition while those in the DD group did not. As participants in the DD group did not frequently use an error correction phase, it was concluded that delayed visual kinesthetic feedback was not used to calibrate kinesthetic feedback modalities. In Retention, significant condition by group interactions, on most measures, indicated that the removal feedback immediately and significantly affected the performance of the CD group, where as the performance of the KR, Static and DD groups deteriorated after the one week retention interval. It was concluded from these data that the delayed feedback did not induce the disrupting or guiding qualities that concurrent visual feedback did. In addition, these findings supported the Guidance Hypothesis (Salmoni etal., 1984). During both Acquisition and Retention, shifts in end position were found to be concomitant to shifts in start position. That is participants overshot the target when they began their movement with their elbow in the most extended position, and progressively shortened their movement as the start position moved closer to their mid-line. As participants were aiming to a common end point and not a series of targets, 45° from the start positions, it appeared that participants coded the movement endpoint. This effect was most pronounced for participants practicing with delayed feedback; as participants in the CD group accurately hit the target in acquisition by making visually based on-line corrections to the initial end-point code. In Retention, however, the CD group overshot the target and, like the other three groups, produced movements to a common end point. That participants were coding their movements to end at a single common end point rather than traverse a particular distance is well accounted for by the Equilibrium Point Hypothesis (Feldman, 1986). Indeed an equilibrium point interpretation was used to explain these findings.