title: Transcranial direct current stimulation (tDCS) over primary motor cortex leg area promotes dynamic balance task performance.
abstract: OBJECTIVE
  The aim of the study was to investigate the effects of facilitatory anodal tDCS (a-tDCS) applied over the leg area of the primary motor cortex on learning a complex whole-body dynamic balancing task (DBT). We hypothesized that a-tDCS during DBT enhances learning performance compared to sham tDCS (s-tDCS).
  
  
  METHODS
  In a randomized, parallel design, we applied either a-tDCS (n=13) or s-tDCS (n=13) in a total of 26 young subjects while they perform the DBT. Task performance and error rates were compared between groups. Additionally, we investigated the effect of tDCS on the relationship between performance and kinematic variables capturing different aspects of task execution.
  
  
  RESULTS
  A-tDCS over M1 leg area promotes balance performance in a DBT relative to s-tDCS, indicated by higher performance and smaller error scores. Furthermore, a-tDCS seems to mediate the relationship between DBT performance and the kinematic variable velocity.
  
  
  CONCLUSIONS
  Our findings provide novel evidence for the ability of tDCS to improve dynamic balance learning, a fact, particularly important in the context of treating balance and gait disorders.
  
  
  CONCLUSIONS
  TDCS facilitates dynamic balance performance by strengthening the inverse relationship of performance and velocity, thus making tDCS one potential technique to improve walking ability or help to prevent falls in patients in the future.
authors.affiliation: Max Planck Institute for Human Cognitive and Brain Sciences, Department of Neurology, D-04103 Leipzig, Germany.
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Kaminski
authors.affiliation: Max Planck Institute for Human Cognitive and Brain Sciences, Department of Neurology, D-04103 Leipzig, Germany; Cerebral Imaging Centre, Douglas Mental Health Institute, Department of Psychiatry, McGill University, Montreal, Quebec, Canada.
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Steele
authors.affiliation: Max Planck Institute for Human Cognitive and Brain Sciences, Department of Neurology, D-04103 Leipzig, Germany; Institute for General Kinesiology and Exercise Science, Faculty of Sport Science, University of Leipzig, Leipzig, Germany.
authors.forename: Maike
authors.initials: M
authors.lastname: Hoff
authors.affiliation: Max Planck Institute for Human Cognitive and Brain Sciences, Department of Neurology, D-04103 Leipzig, Germany; Department of Experimental Psychology and Methods, Faculty of Psychology, University of Leipzig, Leipzig, Germany.
authors.forename: Christopher
authors.initials: C
authors.lastname: Gundlach
authors.affiliation: Max Planck Institute for Human Cognitive and Brain Sciences, Department of Neurology, D-04103 Leipzig, Germany.
authors.forename: Viola
authors.initials: V
authors.lastname: Rjosk
authors.affiliation: Max Planck Institute for Human Cognitive and Brain Sciences, Department of Neurology, D-04103 Leipzig, Germany.
authors.forename: Bernhard
authors.initials: B
authors.lastname: Sehm
authors.affiliation: Max Planck Institute for Human Cognitive and Brain Sciences, Department of Neurology, D-04103 Leipzig, Germany; Mind and Brain Institute, Charité and Humboldt University, D-10117 Berlin, Germany.
authors.forename: Arno
authors.initials: A
authors.lastname: Villringer
authors.affiliation: Max Planck Institute for Human Cognitive and Brain Sciences, Department of Neurology, D-04103 Leipzig, Germany; Institute for General Kinesiology and Exercise Science, Faculty of Sport Science, University of Leipzig, Leipzig, Germany. Electronic address: patrick.ragert@uni-leipzig.de.
authors.forename: Patrick
authors.initials: P
authors.lastname: Ragert
mesh_terms: D000328:Adult; D001696:Biomechanical Phenomena; D005260:Female; D006801:Humans; D007866:Leg / Q000294:innervation* / Q000502:physiology; D008297:Male; D009044:Motor Cortex / Q000502:physiology*; D004856:Postural Balance; D065908:Transcranial Direct Current Stimulation
keywords: Balance in humans; Kinematics; Non-invasive brain stimulation; Velocity