altered perceptual sensitivity to kinematic invariants in parkinsons disease改变感知敏感性在帕金森病运动不变量.pdfVIP

Altered Perceptual Sensitivity to Kinematic Invariants in Parkinson’s Disease 1,2 3 1 Eran Dayan *, Rivka Inzelberg , Tamar Flash 1 Department of Computer Science and Applied Mathematics, The Weizmann Institute of Science, Rehovot, Israel, 2 Department of Neurobiology, The Weizmann Institute of Science, Rehovot, Israel, 3 Department of Neurology, The Sagol Neuroscience Center, Sheba Medical Center, Tel Hashomer and Tel Aviv University, Tel Aviv, Israel Abstract Ample evidence exists for coupling between action and perception in neurologically healthy individuals, yet the precise nature of the internal representations shared between these domains remains unclear. One experimentally derived view is that the invariant properties and constraints characterizing movement generation are also manifested during motion perception. One prominent motor invariant is the ‘‘two-third power law,’’ describing the strong relation between the kinematics of motion and the geometrical features of the path followed by the hand during planar drawing movements. The two-thirds power law not only characterizes various movement generation tasks but also seems to constrain visual perception of motion. The present study aimed to assess whether motor invariants, such as the two thirds power law also constrain motion perception in patients with Parkinson’s disease (PD). Patients with PD and age-matched controls were asked to observe the movement of a light spot rotating on an elliptical path and to modify its velocity until it appeared to move most uniformly. As in previous reports controls tended to choose those movements close to obeying the two-thirds power law as most uniform. Patients with PD displayed a more variable behavior, choosing on average, movements closer but not equal to a