This research will develop a tactile sensor system for the insensate hand. loss of sensation in the hand can be caused by trauma to the peripheral nerves or a spinal cord injury. Peripheral neuropathy can also be caused by diseases such as diabetes or infection. The results are a major loss of hand function. Preliminary research using a new conductive polymer to measure pressure distributions under the insensate foot shows promise. This sensor (Interlink) changes its resistance in response to pressure changes. The sensor is less than 1 mm thick and can be made in any size. Research would (1) Develop a means of ruggedly attaching the lead wires so they can withstand the abuse of high pressures developed during grasp. (2) Develop a means of encapsulation that will permit the sensors to be immersed in water. (3) Develop a glove to hold the sensors in place, which will not impede normal use. A likely candidate is the open-mesh spandex material used for girdles. (4) Determine the location of sensors for optimal tactile sensation using a limited number (for example 16) of sensors. (5) Determine the optimal method and location for providing force feedback using an alternative pathway to the brain. Electrotactile and vibrotactile stimulation are most promising. (6) Determine the characteristics of each element of the system, especially accuracy, repeatability, and durability. (7) Evaluate the system on normals who have tactile sensitivity diminished using padding between the glove and skin or cooling the palmar surface. Tests would include manual dexterity, tactile sensitivity, tactile gradient, detection of contact manual control, and grip force. (8) Make the system available to physicians who treat patients with insensate hands. (9) Investigate alternative sensors such as capacitive, semiconductor strain gage, and optical sensors as a possible improvement.

National Institute of Health (NIH)
National Institute of Neurological Disorders and Stroke (NINDS)
Research Project (R01)
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Surgery, Anesthesiology and Trauma Study Section (SAT)
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University of Wisconsin Madison
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