HEMISPHERIC-ASYMMETRY IN THE VISUAL CONTRIBUTION TO POSTURAL CONTROL IN HEALTHY-ADULTS

THIS study was carried out in order to test the hypothesis of a right hemisphere dominance in the visual control of body balance. Eight heal thy adults were subjected to a self-regulated lateral balance task, pe rformed while sitting on a rocking platform. Four visual conditions we re tested: open eyes with normal vision, closed eyes in the dark, left visual field-right hemisphere and right visual field-left hemisphere. Head and support displacements in the roll plane were recorded by mea ns of an optoelectronic system. Two main results emerged from this stu dy: (1) head stabilization in space was much more efficient in the lef t visual field-right hemisphere condition than in the three other visu al conditions, and (2) althought vision played an important role in th e body stability whatever the anatomical level, there was no right hem isphere dominance at the pelvic level. A clear right hemisphere domina nce was thus demonstrated as regards the visual contribution to head s tabilization in space.