title: Low-frequency repetitive TMS plus anodal transcranial DCS prevents transient decline in bimanual movement induced by contralesional inhibitory rTMS after stroke.
abstract: BACKGROUND
  Low-frequency repetitive transcranial magnetic stimulation (rTMS) over the unaffected motor cortex may improve motor function of the paretic hand after stroke. However, low-frequency rTMS might adversely affect bimanual movement by decreasing transcallosal function.
  
  
  OBJECTIVE
  The authors investigated whether combined administration of rTMS and transcranial direct current stimulation (tDCS) prevents deterioration of bimanual movement induced by low-frequency rTMS over the unaffected hemisphere.
  
  
  METHODS
  A total of 27 participants with chronic subcortical stroke were randomly assigned to receive either 1 Hz rTMS over the unaffected hemisphere, anodal tDCS over the affected hemisphere, or a combination of rTMS and tDCS. All patients performed a pinching motor-training task after stimulation. Bimanual movement and transcallosal inhibition (TCI) were evaluated after stimulation.
  
  
  RESULTS
  rTMS and rTMS-tDCS enhanced the motor training effect on the paretic hand. rTMS decreased bimanual coordination and reduced TCI from the unaffected to the affected hemisphere (TCI(unaff-aff)). rTMS-tDCS changed TCI balance of both hemispheres but did not affect bimanual coordination or TCI(unaff-aff). The change in bimanual coordination was negatively correlated with TCI(unaff-aff). Following stimulation, improvement in the pinch force in the paretic hand was negatively correlated with TCI balance.
  
  
  CONCLUSIONS
  Inhibitory rTMS over the unaffected hemisphere transiently caused deterioration of bimanual movements for the current task in stroke patients. This short-term decline was prevented by combined administration of low-frequency rTMS over the unaffected hemisphere and anodal tDCS over the affected hemisphere. These responses to bihemispheric stimulation suggest possible caution and opportunities for the rehabilitation of hand function after stroke.
authors.affiliation: Department of Physical Medicine and Rehabilitation, Tohoku University Graduates School of Medicine. 2-1 Seiryo-cho, Aobaku, Sendai, 980-8575, Japan. naoyuki@m.tohoku.ac.jp
authors.forename: Naoyuki
authors.initials: N
authors.lastname: Takeuchi
authors.forename: Takeo
authors.initials: T
authors.lastname: Tada
authors.forename: Yuichiro
authors.initials: Y
authors.lastname: Matsuo
authors.forename: Katsunori
authors.initials: K
authors.lastname: Ikoma
mesh_terms: D000368:Aged; D000704:Analysis of Variance; D055592:Biophysical Phenomena / Q000502:physiology; D001921:Brain / Q000503:physiopathology; D004599:Electric Stimulation Therapy / Q000379:methods*; D004576:Electromyography; D019054:Evoked Potentials, Motor / Q000502:physiology; D005260:Female; D007839:Functional Laterality / Q000502:physiology*; D006801:Humans; D016014:Linear Models; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009069:Movement Disorders / Q000175:diagnosis / Q000209:etiology* / Q000517:prevention & control*; D009433:Neural Inhibition / Q000502:physiology; D010812:Physical Stimulation / Q000009:adverse effects; D011597:Psychomotor Performance / Q000502:physiology; D011712:Pyramidal Tracts / Q000503:physiopathology; D020521:Stroke / Q000473:pathology; D000071939:Stroke Rehabilitation; D013997:Time Factors; D014057:Tomography, X-Ray Computed; D050781:Transcranial Magnetic Stimulation / Q000009:adverse effects*