Balance benefits from noisy insoles

If Granny has trouble keeping her equilibrium, it may be because her feet have become less sensitive to pressure changes. Boston scientists have found that they can diminish swaying in elderly people by sending subliminal, erratic vibrations to the bottoms of the seniors’ feet. This subtle postural therapy relies on a principle known as stochastic resonance, whereby noise improves signal recognition in a system such as the nerves (SN: 11/23/96, p.