Print Email Facebook Twitter Sensory Weighting of Force and Position Feedback in Human Motor Control Tasks Title Sensory Weighting of Force and Position Feedback in Human Motor Control Tasks Author Mugge, W. Schuurmans, J. Schouten, A.C. Van der Helm, F.C.T. Faculty Mechanical, Maritime and Materials Engineering Department Biomechanical Engineering Date 2009-04-02 Abstract In daily life humans integrate force and position feedback from mechanoreceptors, proprioception, and vision. With handling relatively soft, elastic objects, force and position are related and can be integrated to improve the accuracy of an estimate of either one. Sensory weighting between different sensory systems (e.g., vision and proprioception) has been extensively studied. This study investigated whether similar weighting can be found within the proprioceptive sensory system, more specifically between the modalities force and position. We hypothesized that sensory weighting is governed by object stiffness: position feedback is weighted heavier on soft objects (large deflections), while force feedback is weighted heavier on stiff objects (small deflections). Subjects were instructed to blindly reproduce either position or force while holding a one degree of freedom haptic manipulator that simulated a linear spring with one of four predetermined stiffnesses. In catch trials the spring was covertly replaced by a nonlinear spring. The difference in force (?F) and position (?X) between the regular and the catch trials revealed the sensory weighting between force and position feedback. A maximum likelihood estimation model predicted that: (1) task instruction did not affect the outcome measures, and (2) force feedback is weighted heavier with increasing object stiffness as was hypothesized. Both effects were found experimentally, and the subjects’ sensory weighting closely resembled the optimal model predictions. To conclude, this study successfully demonstrated sensory weighting within the proprioceptive system. To reference this document use: http://resolver.tudelft.nl/uuid:0b66b626-c2a0-4eb4-87c6-ba4fabad93a3 Publisher Society for Neuroscience ISSN 0270-6474 Source Journal of Neuroscience, 29 (17), 2009 Part of collection Institutional Repository Document type journal article Rights (c) 2009 Creative Commons 3.0 Files PDF Mugge_2009-1.pdf 271.25 KB Close viewer /islandora/object/uuid%3A0b66b626-c2a0-4eb4-87c6-ba4fabad93a3/datastream/OBJ/view