Effects of extrinsic feedback on the motor learning after stroke

Abstract

Aim: This study aims to investigate the effects of the type of extrinsic feedback provided equally in terms of timing and frequency of delivery on the motor learning after stroke. Methods: Twenty post-stroke individuals were distributed randomly into two groups according to the type of feedback provided: knowledge of performance experimental group (KPEG) and knowledge of results experimental group (KREG). Additionally, a control group (CG) was consisted of 20 healthy individuals age- and feedback-matched with the experimental groups. The task was a pointing skill performed in a virtual reality system. The acquisition phase consisted of 3 days/ 75 trials per day. Two retention tests (ret1 and ret2) were run after four days from the acquisition phase. Dependent variable measures were defined by motor performance and movement pattern. Results: The statistical analysis showed interaction effect F(3,108 = 49.13, p = 0.01) among KPEG and KREG. Based on the motor performance parameters (score) the KPEG improved performance significantly from pre to post (p = 0.001), and maintain it from pre to ret1 (p = 0.002), and from the pre to ret2 (p = 0.001). However, the KREG only showed a difference in motor performance from the pre to post (p = 0.003). Compared to the KREG, the KPEG showed improvement on the movement pattern based on the smoothness (p = 0.004), which suggests that the KPEG performed more corrections of movements in relation to the CG and KREG groups. Conclusion: These findings suggest that KP allowed better motor learning in individuals after stroke.