title: Transcranial brain stimulation to promote functional recovery after stroke.
abstract: OBJECTIVE
  Noninvasive brain stimulation (NIBS) is increasingly used to enhance the recovery of function after stroke. The purpose of this review is to highlight and discuss some unresolved questions that need to be addressed to better understand and exploit the potential of NIBS as a therapeutic tool.
  
  
  RESULTS
  Recent meta-analyses showed that the treatment effects of NIBS in patients with stroke are rather inconsistent across studies and the evidence for therapeutic efficacy is still uncertain. This raises the question of how NIBS can be developed further to improve its therapeutic efficacy.
  
  
  CONCLUSIONS
  This review addressed six questions: How does NIBS facilitate the recovery of function after stroke? Which brain regions should be targeted by NIBS? Is there a particularly effective NIBS modality that should be used? Does the location of the stroke influence the therapeutic response? How often should NIBS be repeated? Is the functional state of the brain during or before NIBS relevant to therapeutic efficacy of NIBS? We argue that these questions need to be tackled to obtain sufficient mechanistic understanding of how NIBS facilitates the recovery of function. This knowledge will be critical to fully unfold the therapeutic effects of NIBS and will pave the way towards adaptive NIBS protocols, in which NIBS is tailored to the individual patient.
authors.affiliation: aDanish Research Centre for Magnetic Resonance, Centre for Functional and Diagnostic Imaging and Research, Copenhagen University Hospital Hvidovre, Hvidovre bDepartment of Neurology, Copenhagen University Hospital Bispebjerg, Copenhagen, Denmark.
authors.forename: Estelle
authors.initials: E
authors.lastname: Raffin
authors.forename: Hartwig R
authors.initials: HR
authors.lastname: Siebner
mesh_terms: D006801:Humans; D015201:Meta-Analysis as Topic; D020127:Recovery of Function / Q000502:physiology*; D020521:Stroke / Q000628:therapy*; D050781:Transcranial Magnetic Stimulation