title: Ablation of the inferior olive prevents H-reflex down-conditioning in rats.
abstract: We evaluated the role of the inferior olive (IO) in acquisition of the spinal cord plasticity that underlies H-reflex down-conditioning, a simple motor skill. The IO was chemically ablated before a 50-day exposure to an operant conditioning protocol that rewarded a smaller soleus H-reflex. In normal rats, down-conditioning succeeds (i.e., H-reflex size decreases at least 20%) in 80% of animals. Down-conditioning failed in every IO-ablated rat (P< 0.001 vs. normal rats). IO ablation itself had no long-term effect on H-reflex size. These results indicate that the IO is essential for acquisition of a down-conditioned H-reflex. With previous data, they support the hypothesis that IO and cortical inputs to cerebellum enable the cerebellum to guide sensorimotor cortex plasticity that produces and maintains the spinal cord plasticity that underlies the down-conditioned H-reflex. They help to further define H-reflex conditioning as a model for understanding motor learning and as a new approach to enhancing functional recovery after trauma or disease.
authors.affiliation: National Center for Adaptive Neurotechnologies, Wadsworth Center, New York State Department of Health, Albany, New York; Department of Biomedical Sciences, State University of New York, Albany, New York; xiangyang.chen@health.ny.gov.
authors.forename: Xiang Yang
authors.initials: XY
authors.lastname: Chen
authors.affiliation: National Center for Adaptive Neurotechnologies, Wadsworth Center, New York State Department of Health, Albany, New York;
authors.forename: Yu
authors.initials: Y
authors.lastname: Wang
authors.affiliation: National Center for Adaptive Neurotechnologies, Wadsworth Center, New York State Department of Health, Albany, New York;
authors.forename: Yi
authors.initials: Y
authors.lastname: Chen
authors.affiliation: National Center for Adaptive Neurotechnologies, Wadsworth Center, New York State Department of Health, Albany, New York;
authors.forename: Lu
authors.initials: L
authors.lastname: Chen
authors.affiliation: National Center for Adaptive Neurotechnologies, Wadsworth Center, New York State Department of Health, Albany, New York; Department of Biomedical Sciences, State University of New York, Albany, New York; Department of Neurology, Albany Stratton Department of Veterans Affairs Medical Center, Albany, New York; and Department of Neurology, Columbia University College of Physicians and Surgeons, New York, New York.
authors.forename: Jonathan R
authors.initials: JR
authors.lastname: Wolpaw
mesh_terms: D000818:Animals; D002531:Cerebellum / Q000502:physiology; D003214:Conditioning, Classical; D005071:Evoked Potentials; D006181:H-Reflex; D008297:Male; D009847:Olivary Nucleus / Q000502:physiology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013116:Spinal Cord / Q000502:physiology
keywords: cerebellum; learning; operant conditioning; plasticity; spinal cord