Abstract
Somatosensory feedback provides information about ongoing performance and success of movements. Individuals who experience disrupted somatosensory feedback are often faced with re-learning basic goal-directed movements. The present experiment assessed the impact of induced paresthesia, in an otherwise healthy nervous system, on movement performance. Sixteen healthy young (10 females, M age = 21.7) participants attended two sessions on two separate days and completed four conditions: paresthsia/no paresthesia and vision/no vision of the target. Order of the four conditions and associated target locations were blocked and counterbalanced across participants. Paresthesia was induced using a constant current stimulator and confirmed with standardized sensory testing. Participants performed 100 trials per condition and were motivated to improve their movement time (MT) by providing incentive for accurate movements with associated shorter MTs. Movements were recorded using a 3D motion analysis system (300Hz) and analyzed using a 2 (paresthesia condition) by 2 (vision condition) by 2 (early/ late performance) repeated measures ANOVA. Analyses revealed no significant differences for reaction time or constant error. Although MT and time to peak velocity (ttPV) improved with practice, paresthesia led to significantly longer MTs and ttPV. A paresthesia by vision condition interaction revealed that movement endpoints were more variable without vision only when paresthesia was not present. Findings will be discussed in the context of sensorimotor integration and the implications for upper limb rehabilitation.Acknowledgments: This research was funded by the Manitoba Medical Service Foundation, the Manitoba Health Research Council, and the Natural Sciences and Engineering Research Council of Canada. The authors would like to thank Leah Harpelle, Kelsey Brown, and Michele Berthelette for their assistance with target set-up, data collection, data organization, respectively.