Restoring Diabetic Tactile Sense with Mechanical Noise

Stochastic resonance (SR) is a counterintuitive phenomenon in which slight amounts of noise imparted to a system actually increase its sensitivity to weak stimuli. SR has been shown to produce a demonstrable effect in human sensory cells. In both healthy young and clinical subjects-elderly, diabetics, and stroke sufferers-a notable increase in tactile and proprioceptive sensitivity is seen when electrical or mechanical noise is presented at the site of the stimulus. Dysfunction in the tactile system in diabetics is known to have significant clinical sequelae including gait abnormalities, propensity to fall, and foot ulcers. Diabetic peripheral neuropathy, with its complications, costs the U.S. healthcare system many billions of dollars annually. The goal of the proposed research is to advance early laboratory results toward a therapeutic device for enhancing the tactile sense in diabetic patients. The work will demonstrate the ability of mechanical stimulation to improve sensitivity using two metrics. First, we will determine the magnitude of the SR benefit in diabetics using standard neurological examinations, specifically the Semmes-Weinstein and vibration perception threshold tests. Second, we will explore the functional benefit of mechanical stimulation in stance and sway experiments. Both experiments will give a measure of true functional benefit. PROPOSED COMMERCIAL APPLICATIONS: If successful, the proposed research will lead to medical devices that improve tactile sensitivity in people who suffer from diabetic peripheral neuropathy. This would improve quality of life for these individuals while reducing the costs of caring for them. Additional medical applications include use of technology in stroke, aging, and rehabilitation medicine.