Vagus nerve stimulation (VNS) researchers notched another success with FDA approval of a drug-free rehabilitation system that uses the technology to help patients who have lost mobility in their hands and arms as a result of ischemic stroke regain function. Microtransponder Inc.’s Vivistim pairs rehabilitation exercises with VNS to enhance their impact. The clinical study evaluated by the FDA for the system's approval showed that Vivistim doubled the improvement in upper extremity motor function compared to supervised rehabilitative exercises alone at six weeks and 90 days.