title: Effects of robotically modulating kinematic variability on motor skill learning and motivation.
abstract: It is unclear how the variability of kinematic errors experienced during motor training affects skill retention and motivation. We used force fields produced by a haptic robot to modulate the kinematic errors of 30 healthy adults during a period of practice in a virtual simulation of golf putting. On day 1, participants became relatively skilled at putting to a near and far target by first practicing without force fields. On day 2, they warmed up at the task without force fields, then practiced with force fields that either reduced or augmented their kinematic errors and were finally assessed without the force fields active. On day 3, they returned for a long-term assessment, again without force fields. A control group practiced without force fields. We quantified motor skill as the variability in impact velocity at which participants putted the ball. We quantified motivation using a self-reported, standardized scale. Only individuals who were initially less skilled benefited from training; for these people, practicing with reduced kinematic variability improved skill more than practicing in the control condition. This reduced kinematic variability also improved self-reports of competence and satisfaction. Practice with increased kinematic variability worsened these self-reports as well as enjoyment. These negative motivational effects persisted on day 3 in a way that was uncorrelated with actual skill. In summary, robotically reducing kinematic errors in a golf putting training session improved putting skill more for less skilled putters. Robotically increasing kinematic errors had no performance effect, but decreased motivation in a persistent way.
authors: Department of Mechanical and Aerospace Engineering, University of California, Irvine, California; jeduarte@uci.edu.
authors: Jaime E
authors: JE
authors: Duarte
authors: Department of Mechanical and Aerospace Engineering, University of California, Irvine, California; Department of Biomedical Engineering, University of California, Irvine, California; and Department of Anatomy and Neurobiology, University of California, Irvine, California.
authors: David J
authors: DJ
authors: Reinkensmeyer
mesh_terms: D000328:Adult; D054874:Athletic Performance / Q000502:physiology*; D005260:Female; D006055:Golf / Q000502:physiology*; D006801:Humans; D007858:Learning / Q000502:physiology*; D008297:Male; D009042:Motivation / Q000502:physiology*; D009048:Motor Skills / Q000502:physiology*; D057181:Pleasure; D015203:Reproducibility of Results; D012371:Robotics / Q000379:methods*; D012680:Sensitivity and Specificity; D055815:Young Adult
keywords: motivation; motor learning; motor skill; movement variability; robotic training