title: Effects of Subdural Monopolar Cortical Stimulation Paired With Rehabilitative Training on Behavioral and Neurophysiological Recovery After Cortical Ischemic Stroke in Adult Squirrel Monkeys.
abstract: BACKGROUND
  Cortical stimulation (CS) combined with rehabilitative training (RT) has proven effective for enhancing poststroke functional recovery in rats, but human clinical trials have had mixed outcomes.
  
  
  OBJECTIVE
  To assess the efficacy of CS/RT versus RT in a nonhuman primate model of cortical ischemic stroke.
  
  
  METHODS
  Squirrel monkeys learned a pellet retrieval task, then received an infarct to the distal forelimb (DFL) representation of primary motor cortex. A subdural monopolar electrode was implanted over the spared DFL representation in dorsal premotor cortex (PMD). Seven weeks postinfarct, monkeys underwent 4 to 6 weeks of RT (n = 8) or CS/RT (n = 7; 100 Hz, cathodal current) therapy. Behavioral performance was assessed before and after infarct, prior to therapy, and 1 and 12 weeks posttherapy (follow-up). The primary outcome measure was motor performance at 1 week posttherapy. Secondary outcomes included follow-up performance at 12 weeks and treatment-related changes in neurophysiological maps of spared DFL representations.
  
  
  RESULTS
  While postinfarct performance deficits were found in all monkeys, both groups demonstrated similar recovery profiles, with no difference in motor recovery between the RT and CS/RT groups. Posttherapy, PMD DFL area was significantly expanded in the RT group but not the CS/RT group. A significant relationship was found between motor recovery and DFL expansion in premotor cortex.
  
  
  CONCLUSIONS
  Results suggest that the specific parameters utilized here were not optimal for promoting behavioral recovery in nonhuman primates. Though CS/RT has consistently shown efficacy in rat stroke models, the present finding has cautionary implications for translation of CS/RT therapy to clinical populations.
authors.affiliation: University of Texas Southwestern Medical Center, Dallas, TX, USA erik.plautz@utsouthwestern.edu.
authors.forename: Erik J
authors.initials: EJ
authors.lastname: Plautz
authors.affiliation: University of Kansas Medical Center, Kansas City, KS, USA.
authors.forename: Scott
authors.initials: S
authors.lastname: Barbay
authors.affiliation: University of Kansas Medical Center, Kansas City, KS, USA.
authors.forename: Shawn B
authors.initials: SB
authors.lastname: Frost
authors.affiliation: Massasoit Community College, Brockton, MA, USA.
authors.forename: Elena V
authors.initials: EV
authors.lastname: Zoubina
authors.affiliation: University of Texas Southwestern Medical Center, Dallas, TX, USA.
authors.forename: Ann M
authors.initials: AM
authors.lastname: Stowe
authors.affiliation: University of Montreal, Montreal, Quebec, Canada.
authors.forename: Numa
authors.initials: N
authors.lastname: Dancause
authors.affiliation: University of Kansas Medical Center, Kansas City, KS, USA.
authors.forename: Ines
authors.initials: I
authors.lastname: Eisner-Janowicz
authors.affiliation: University of Kansas Medical Center, Kansas City, KS, USA.
authors.forename: Scott D
authors.initials: SD
authors.lastname: Bury
authors.affiliation: University of Kansas Medical Center, Kansas City, KS, USA.
authors.forename: Michael D
authors.initials: MD
authors.lastname: Taylor
authors.affiliation: University of Kansas Medical Center, Kansas City, KS, USA.
authors.forename: Randolph J
authors.initials: RJ
authors.lastname: Nudo
mesh_terms: D000818:Animals; D001522:Behavior, Animal; D002545:Brain Ischemia / Q000534:rehabilitation / Q000628:therapy*; D004195:Disease Models, Animal; D004599:Electric Stimulation Therapy / Q000379:methods* / Q000592:standards; D005260:Female; D008297:Male; D009044:Motor Cortex / Q000503:physiopathology*; D009473:Neuronal Plasticity / Q000502:physiology; D020127:Recovery of Function / Q000502:physiology*; D012453:Saimiri; D020521:Stroke / Q000628:therapy*; D000071939:Stroke Rehabilitation
keywords: implanted stimulation electrodes; neuronal plasticity; premotor cortex; primary motor cortex; primate