title: Body response to binaural monopolar galvanic vestibular stimulation in humans.
abstract: We investigated the possibility of obtaining an anteroposterior body response to galvanic vestibular stimulation (GVS) by applying an equivalent stimulus to both sides of the vestibular apparatus. An original 'double fronto-mastoidal' stimulation was used on eight subjects standing with their head facing forwards. Both the onset and the cut-off of the current did induce an anteroposterior body tilt, without any lateral component. The amplitude of the tilt increased as a function of stimulus intensity. GVS evokes anteroposterior or lateral sway of similar spatio-temporal features according to the stimulation configuration. We suggest that the central nervous system makes use of the discrepancy between the left and right vestibular activity to orientate the response: equivalent afferent flows would result in an anteroposterior body response whereas lateral sway is obtained with discrepant ones.
authors.affiliation: Centre de Recherche Cerveau et Cognition, UMR CNRS/UPS/EHESS 5549, Faculté de Médecine, Toulouse, France. severac@cerco.ups-tlse.fr
authors.forename: A
authors.initials: A
authors.lastname: Séverac Cauquil
authors.forename: M F
authors.initials: MF
authors.lastname: Gervet
authors.forename: M
authors.initials: M
authors.lastname: Ouaknine
mesh_terms: D000328:Adult; D004558:Electric Stimulation; D007839:Functional Laterality / Q000502:physiology*; D006801:Humans; D009949:Orientation / Q000502:physiology*; D011187:Posture / Q000502:physiology*; D014722:Vestibule, Labyrinth / Q000502:physiology*