title: Restoration of upper limb movement via artificial corticospinal and musculospinal connections in a monkey with spinal cord injury.
abstract: Functional loss of limb control in individuals with spinal cord injury or stroke can be caused by interruption of corticospinal pathways, although the neural circuits located above and below the lesion remain functional. An artificial neural connection that bridges the lost pathway and connects cortical to spinal circuits has potential to ameliorate the functional loss. We investigated the effects of introducing novel artificial neural connections in a paretic monkey that had a unilateral spinal cord lesion at the C2 level. The first application bridged the impaired spinal lesion. This allowed the monkey to drive the spinal stimulation through volitionally controlled power of high-gamma activity in either the premotor or motor cortex, and thereby to acquire a force-matching target. The second application created an artificial recurrent connection from a paretic agonist muscle to a spinal site, allowing muscle-controlled spinal stimulation to boost on-going activity in the muscle. These results suggest that artificial neural connections can compensate for interrupted descending pathways and promote volitional control of upper limb movement after damage of descending pathways such as spinal cord injury or stroke.
authors.affiliation: Department of Physiology & Biophysics, University of Washington Seattle, WA, USA ; Washington National Primate Research Center, University of Washington Seattle, WA, USA ; Precursory Research for Embryonic Science and Technology, Japan Science and Technology Agency Tokyo, Japan.
authors.forename: Yukio
authors.initials: Y
authors.lastname: Nishimura
authors.forename: Steve I
authors.initials: SI
authors.lastname: Perlmutter
authors.forename: Eberhard E
authors.initials: EE
authors.lastname: Fetz
mesh_terms: D000818:Animals; D004558:Electric Stimulation / Q000379:methods; D004567:Electrodes, Implanted; D008254:Macaca nemestrina; D008297:Male; D009068:Movement / Q000502:physiology*; D011597:Psychomotor Performance / Q000502:physiology; D011712:Pyramidal Tracts / Q000502:physiology*; D020127:Recovery of Function / Q000502:physiology*; D013119:Spinal Cord Injuries / Q000503:physiopathology / Q000628:therapy*; D034941:Upper Extremity / Q000294:innervation / Q000502:physiology*
keywords: artificial neural connection; brain–computer interface; hand; local field potential; monkey; muscle; spinal cord; spinal cord injury