title: Recovery of post stroke proximal arm function, driven by complex neuroplastic bilateral brain activation patterns and predicted by baseline motor dysfunction severity.
abstract: OBJECTIVE
  Neuroplastic changes that drive recovery of shoulder/elbow function after stroke have been poorly understood. The purpose of this study was to determine the relationship between neuroplastic brain changes related to shoulder/elbow movement control in response to treatment and recovery of arm motor function in chronic stroke survivors.
  
  
  METHODS
  Twenty-three chronic stroke survivors were treated with 12 weeks of arm rehabilitation. Outcome measures included functional Magnetic Resonance Imaging (fMRI) for the shoulder/elbow components of reach and a skilled motor function test (Arm Motor Abilities Test, AMAT), collected before and after treatment.
  
  
  RESULTS
  We observed two patterns of neuroplastic changes that were associated with gains in motor function: decreased or increased task-related brain activation. Those with significantly better motor function at baseline exhibited a decrease in brain activation in response to treatment, evident in the ipsilesional primary motor and contralesional supplementary motor regions; in contrast, those with greater baseline motor impairment, exhibited increased brain activation in response to treatment. There was a linear relationship between greater functional gain (AMAT) and increased activation in bilateral primary motor, contralesional primary and secondary sensory regions, and contralesional lateral premotor area, after adjusting for baseline AMAT, age, and time since stroke.
  
  
  CONCLUSIONS
  Recovery of functional reach involves recruitment of several contralesional and bilateral primary motor regions. In response to intensive therapy, the direction of functional brain change (i.e., increase or decrease in task-related brain recruitment) for shoulder/elbow reach components depends on baseline level of motor function and may represent either different phases of recovery or different patterns of neuroplasticity that drive functional recovery.
authors.affiliation: Department of Neurology, Case Western Reserve University School of Medicine Cleveland, OH, USA ; Neurology Service, Cleveland VA Medical Center Cleveland, OH, USA.
authors.forename: Svetlana
authors.initials: S
authors.lastname: Pundik
authors.affiliation: Neurology Service, Cleveland VA Medical Center Cleveland, OH, USA.
authors.forename: Jessica P
authors.initials: JP
authors.lastname: McCabe
authors.affiliation: Neurology Service, Cleveland VA Medical Center Cleveland, OH, USA.
authors.forename: Ken
authors.initials: K
authors.lastname: Hrovat
authors.affiliation: Neurology Service, Cleveland VA Medical Center Cleveland, OH, USA.
authors.forename: Alice Erica
authors.initials: AE
authors.lastname: Fredrickson
authors.affiliation: Department of Neurology, Case Western Reserve University School of Medicine Cleveland, OH, USA ; Department of Epidemiology and Biostatistics, Case Western Reserve University Cleveland, OH, USA.
authors.forename: Curtis
authors.initials: C
authors.lastname: Tatsuoka
authors.affiliation: Department of Epidemiology and Biostatistics, Case Western Reserve University Cleveland, OH, USA.
authors.forename: I Jung
authors.initials: IJ
authors.lastname: Feng
authors.affiliation: Department of Neurology, College of Medicine, University of Florida Gainsville, FL, USA ; North Florida/South Georgia, Gainesville VA Medical Center, Brain Rehabilitation Research Center Gainsville, FL, USA.
authors.forename: Janis J
authors.initials: JJ
authors.lastname: Daly
keywords: chronic stroke; functional Magnetic Resonance Imaging; motor learning; motor recovery; motor rehabilitation; neuroplasticity; shoulder/elbow movement task; upper extremity motor function