An intrinsically soft organic electrode consisting of poly(3,4‐ethylenedioxythiophene)‐modified polyurethane (PEDOT‐PU) is embedded into a bilayer film of polyvinyl alcohol (PVA) hydrogels for developing a self‐closing cuff electrode for neuromodulation. The curled form of the PVA hydrogel is prepared by releasing internal stress in the bilayer structure. The inner diameter of the cuff electrode is set to less than 2 mm for immobilization to the vagus nerve (VN) of humans and pigs. The stability of the immobilization is examined, while the pressure applied to a nerve bundle is at a harmless level (≈200 Pa). Since the electrode is totally organic, MRI measurements can be conducted without image artifacts. The large electric capacitance of the PEDOT‐PU (≈27 mF cm−2) ensures a safe stimulation of living tissues without Faradaic reactions. The practical performance of the cuff electrode for VN stimulation is demonstrated by observation of bradycardia induction in a pig.

Vagus Nerve Stimulation In article 2201627 by Matsuhiko Nishizawa and co‐workers, a totally organic hydrogel‐based cuff‐type stimulation electrode with self‐closing properties is developed. The cuff electrode is spontaneously immobilized to the vagus nerve by wrapped around the nerve bundle with harmless pressure. The organic nature of the electrode is compatible with MRI imaging.