Altered sensory function and balance in older persons.

The effects of three different visual inputs (eyes open, eyes closed, and inaccurate) while standing on an unstable surface (respectively, UEO, UEC, UI) were compared in a group of healthy elderly community dwellers (N = 239; mean age 76) and young (N = 34; mean age 34) adults. Subjects with medical factors known to affect balance were excluded. Body sway and loss of balance measured dynamic force platform (EquiTest, NeuroCom International). Visual and somatosensory inputs were rendered inaccurate through tilting of the standing surface and/or the visual surround proportional to the subject's angle of sway (sway-referencing). The elderly group had significantly more difficulty balancing during UEC and UI, and a larger proportion lost their balance during UI. These findings are compared to those of other dynamic posturography studies in which sensory inputs were controlled. Issues of age, frailty, screening, and test protocol are addressed in order to account for differences in results among studies.