title: Dual-hemisphere transcranial direct current stimulation improves performance in a tactile spatial discrimination task.
abstract: OBJECTIVE
  The aim of this study was to test the hypothesis that dual-hemisphere transcranial direct current stimulation (tDCS) over the primary somatosensory cortex (S1) could improve performance in a tactile spatial discriminative task, compared with uni-hemisphere or sham tDCS.
  
  
  METHODS
  Nine healthy adults participated in this double-blind, sham-controlled, and cross-over design study. The performance in a grating orientation task (GOT) in the right index finger was evaluated before, during, immediately after and 30min after the dual-hemisphere, uni-hemisphere (1mA, 20min), or sham tDCS (1mA, 30s) over S1. In the dual-hemisphere and sham conditions, anodal tDCS was applied over the left S1, and cathodal tDCS was applied over the right S1. In the uni-hemisphere condition, anodal tDCS was applied over the left S1, and cathodal tDCS was applied over the contralateral supraorbital front.
  
  
  RESULTS
  The percentage of correct responses on the GOT during dual-hemisphere tDCS was significantly higher than that in the uni-hemisphere or sham tDCS conditions when the grating width was set to 0.75mm (all p<0.05).
  
  
  CONCLUSIONS
  Dual-hemisphere tDCS over S1 improved performance in a tactile spatial discrimination task in healthy volunteers.
  
  
  CONCLUSIONS
  Dual-hemisphere tDCS may be a useful strategy to improve sensory function in patients with sensory dysfunctions.
authors.affiliation: Tokyo Bay Rehabilitation Hospital, Chiba, Japan.
authors.forename: Shuhei
authors.initials: S
authors.lastname: Fujimoto
authors.affiliation: Tokyo Bay Rehabilitation Hospital, Chiba, Japan; Keio University School of Medicine, Tokyo, Japan.
authors.forename: Tomofumi
authors.initials: T
authors.lastname: Yamaguchi
authors.affiliation: Tokyo Bay Rehabilitation Hospital, Chiba, Japan; Keio University School of Medicine, Tokyo, Japan.
authors.forename: Yohei
authors.initials: Y
authors.lastname: Otaka
authors.affiliation: Tokyo Bay Rehabilitation Hospital, Chiba, Japan.
authors.forename: Kunitsugu
authors.initials: K
authors.lastname: Kondo
authors.affiliation: Nagoya Institute of Technology, Aichi, Japan. Electronic address: tanaka1976@gmail.com.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Tanaka
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D001288:Attention / Q000502:physiology; D018592:Cross-Over Studies; D004311:Double-Blind Method; D005260:Female; D007839:Functional Laterality / Q000502:physiology; D006801:Humans; D008297:Male; D009473:Neuronal Plasticity / Q000502:physiology; D010919:Placebos; D012016:Reference Values; D013003:Somatosensory Cortex / Q000502:physiology*; D065855:Spatial Processing / Q000502:physiology*; D011795:Surveys and Questionnaires; D014110:Touch / Q000502:physiology*; D055698:Touch Perception / Q000502:physiology*; D065908:Transcranial Direct Current Stimulation; D050781:Transcranial Magnetic Stimulation; D055815:Young Adult
chemical_list: D010919:Placebos
keywords: Cortical plasticity; Inter-hemispheric inhibition (IHI); Somatosensory cortex; Tactile; Transcranial direct current stimulation (tDCS); Transcranial magnetic stimulation (TMS)