Snip from NYT:
In a study being published in the January issue of The Annals of Neurology, researchers report that vibrating insoles allow diabetics with numb feet and stroke victims with uncertain balance to stand quietly without swaying and losing their balance. The random vibrations, which were so subtle that people did not have any conscious awareness of them, effectively stimulated the neurons on the bottom of their feet. That provided their wobbly balance system with missing information about how their stance was changing moment to moment.
An earlier study using the vibrating insoles had a similar result, said James J. Collins, a professor of biomedical engineering at Boston University who led the research. In that experiment, the vibrations helped elderly subjects stand as steadily as most 20-year-olds.
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