title: Brain Function and Upper Limb Outcome in Stroke: A Cross-Sectional fMRI Study.
abstract: OBJECTIVE
  The nature of changes in brain activation related to good recovery of arm function after stroke is still unclear. While the notion that this is a reflection of neuronal plasticity has gained much support, confounding by compensatory strategies cannot be ruled out. We address this issue by comparing brain activity in recovered patients 6 months after stroke with healthy controls.
  
  
  METHODS
  We included 20 patients with upper limb paresis due to ischemic stroke and 15 controls. We measured brain activation during a finger flexion-extension task with functional MRI, and the relationship between brain activation and hand function. Patients exhibited various levels of recovery, but all were able to perform the task.
  
  
  RESULTS
  Comparison between patients and controls with voxel-wise whole-brain analysis failed to reveal significant differences in brain activation. Equally, a region of interest analysis constrained to the motor network to optimize statistical power, failed to yield any differences. Finally, no significant relationship between brain activation and hand function was found in patients. Patients and controls performed scanner task equally well.
  
  
  CONCLUSIONS
  Brain activation and behavioral performance during finger flexion-extensions in (moderately) well recovered patients seems normal. The absence of significant differences in brain activity even in patients with a residual impairment may suggest that infarcts do not necessarily induce reorganization of motor function. While brain activity could be abnormal with higher task demands, this may also introduce performance confounds. It is thus still uncertain to what extent capacity for true neuronal repair after stroke exists.
authors.affiliation: Centre of Knowledge, Rehabilitation Centre 'De Hoogstraat', Utrecht, The Netherlands; Dept. Rehabilitation & Sports Medicine, Brain Center Rudolf Magnus, UMCU, Utrecht, The Netherlands.
authors.forename: Floor E
authors.initials: FE
authors.lastname: Buma
authors.affiliation: Dept of Neurology & Neurosurgery, Brain Center Rudolf Magnus, UMCU, Utrecht, The Netherlands.
authors.forename: Mathijs
authors.initials: M
authors.lastname: Raemaekers
authors.affiliation: Centre of Knowledge, Rehabilitation Centre 'De Hoogstraat', Utrecht, The Netherlands; Dept. Rehabilitation & Sports Medicine, Brain Center Rudolf Magnus, UMCU, Utrecht, The Netherlands; Dept. Rehabilitation Medicine, Research Institute MOVE Amsterdam, VU University Medical Center, Amsterdam, The Netherlands.
authors.forename: Gert
authors.initials: G
authors.lastname: Kwakkel
authors.affiliation: Dept of Neurology & Neurosurgery, Brain Center Rudolf Magnus, UMCU, Utrecht, The Netherlands.
authors.forename: Nick F
authors.initials: NF
authors.lastname: Ramsey
mesh_terms: D000328:Adult; D000368:Aged; D001921:Brain / Q000503:physiopathology*; D002545:Brain Ischemia / Q000503:physiopathology*; D005260:Female; D007839:Functional Laterality / Q000502:physiology; D059907:Functional Neuroimaging; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009048:Motor Skills / Q000502:physiology; D009473:Neuronal Plasticity / Q000502:physiology; D020127:Recovery of Function / Q000502:physiology*; D020521:Stroke / Q000503:physiopathology*; D034941:Upper Extremity / Q000503:physiopathology*