title: Sensory timing cues improve akinesia of grasping movements in Parkinson's disease: a comparison to the effects of subthalamic nucleus stimulation.
abstract: Five parkinsonian subjects with chronic bilateral stimulation of the subthalamic nucleus and five sex- and age-matched healthy controls grasped, lifted, and held an instrumented object. The grip-lift task was either performed at self-determined speed or in response to an auditory cuing signal. Parkinsonian subjects performed the task with subthalamic nucleus stimulation switched ON and OFF. In Parkinson's disease, stimulation of the subthalamic nucleus and the presentation of auditory timing cues improved akinesia of both the grasp and lift components of the task. The finding that auditory timing cues improve akinesia in the absence of subthalamic nucleus stimulation suggests that the basal ganglia are less involved in the control of movements made in response to environmental cues. However, subthalamic nucleus stimulation caused parkinsonian subjects to apply excessive grip forces, regardless of whether the movement was made under self-determined or externally guided speed conditions. This implies that subthalamic nucleus stimulation produces a generalized upregulation in the gain of all components of a movement without the subtlety of focused control that is required to normalize performance.
authors.affiliation: Sobell Department of Motor Neuroscience and Movement Disorders, Institute of Neurology, University College London, London, United Kingdom. dr.dennis.nowak@gmx.de
authors.forename: Dennis A
authors.initials: DA
authors.lastname: Nowak
authors.forename: Stephen
authors.initials: S
authors.lastname: Tisch
authors.forename: Marwan
authors.initials: M
authors.lastname: Hariz
authors.forename: Patricia
authors.initials: P
authors.lastname: Limousin
authors.forename: Helge
authors.initials: H
authors.lastname: Topka
authors.forename: John C
authors.initials: JC
authors.lastname: Rothwell
mesh_terms: D000054:Acceleration; D000161:Acoustic Stimulation; D000328:Adult; D000978:Antiparkinson Agents / Q000008:administration & dosage; D001307:Auditory Perception / Q000502:physiology; D003131:Combined Modality Therapy; D003463:Cues; D004292:Dominance, Cerebral / Q000502:physiology; D020820:Dyskinesias / Q000503:physiopathology / Q000628:therapy*; D004599:Electric Stimulation Therapy; D005260:Female; D018737:Hand Strength; D006801:Humans; D017770:Lifting; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000503:physiopathology / Q000628:therapy*; D011596:Psychomotor Disorders / Q000503:physiopathology / Q000628:therapy*; D020531:Subthalamic Nucleus / Q000503:physiopathology; D013998:Time Perception / Q000502:physiology
chemical_list: D000978:Antiparkinson Agents