perception,
multisensory,
falls,
balance
Recent research has provided evidence suggesting a link between
inefficient processing of multisensory information and incidence of
falling in older adults. Specifically, Setti et al. (Exp Brain Res
209:375-384, 2011) reported that older adults with a history of falling
were more susceptible than their healthy, age-matched counterparts to
the sound-induced flash illusion. Here, we investigated whether balance
control in fall-prone older adults was directly associated with
multisensory integration by testing susceptibility to the illusion under
two postural conditions: sitting and standing. Whilst standing,
fall-prone older adults had a greater body sway than the age-matched
healthy older adults and their body sway increased when presented with
the audio-visual illusory but not the audio-visual congruent conditions.
We also found an increase in susceptibility to the sound-induced flash
illusion during standing relative to sitting for fall-prone older adults
only. Importantly, no performance differences were found across groups
in either the unisensory or non-illusory multisensory conditions across
the two postures. These results suggest an important link between
multisensory integration and balance control in older adults and have
important implications for understanding why some older adults are prone
to falling.