Coordinate Frame for Proprioception Acuity Changes Accompanying Motor Learning
Abstract
Proprioception is important for skilled motor control. Improvements in proprioception occur in conjunction with motor learning. However, it has not been established whether these improvements occur within intrinsic or extrinsic coordinate frames. In Experiment 1 we gave participants a perceptual test of sensed limb position and a motor learning task in the same location of the workspace or in two different locations of the workspace. Participants performed better on the proprioception test when the motor learning task was completed in the same location as the proprioception test. In Experiment 2 we tested whether this perceptual improvement occurred in an intrinsic or extrinsic coordinate frame. Proprioceptive improvements were observed when participants maintained the same joint angles, but no improvements were found when participants altered their joint angles and maintained the same hand position. This consists with the idea that perceptual changes associated to motor learning occur in an intrinsic coordinate frame.
Keywords: human, proprioception, motor learning, somatosensory cortex, intrinsic coordinate frame, extrinsic coordinate frame, sensory, perceptual