Galvanic vestibular stimulation in humans produces online arm movement deviations when reaching towards memorized visual targets.
Using galvanic vestibular stimulation (GVS), we tested whether a change in vestibular input at the onset of goal-directed arm movements induces deviations in arm trajectory. Eight head-fixed standing subjects were instructed to reach for memorized visual targets in complete darkness. In half of the trials, randomly-selected, a 3 mA bipolar binaural galvanic stimulation of randomly alternating polarity was triggered by the movement onset. Results revealed significant GVS-induced directional shifts of reaching movements towards the anode side. The earliest significant deviations of hand path occurred 240 ms after stimulation onset. The likely goal of these online deviations of arm trajectory was to compensate for a vestibular-evoked apparent change in the spatial relationship between the target and the hand.
Bresciani
J P
JP
UMR Mouvement et Perception, CNRS et Université de la Méditerranée, 163 Avenue de Luminy, Case Postale 910, 13288 Cedex 9, Marseille, France. bresciani@laps.univ-mrs.fr
Blouin
J
J
Popov
K
K
Bourdin
C
C
Sarlegna
F
F
Vercher
J L
JL
Gauthier
G M
GM
D000328:Adult; D001132:Arm; D004558:Electric Stimulation; D006801:Humans; D008568:Memory / Q000502:physiology; D009068:Movement / Q000502:physiology*; D011434:Proprioception / Q000502:physiology; D011597:Psychomotor Performance / Q000502:physiology*; D013028:Space Perception / Q000502:physiology; D014722:Vestibule, Labyrinth / Q000502:physiology*