Fabrication and characterization of multicoil neural probes

There is virtue in long-term neural stimulation for the treatment of symptoms associated with neurological disorders. To date, implanted electrical probes¹ have had great success in mitigating seizures and symptoms of e.g. Parkinson’s disease and other pathologies. However, chronic stimulation has proven challenging as electrode performance degrades over time. Alternatively, new technologies are exploring electrical stimulation via changing magnetic fields², harnessing the physical properties set out by Maxwell’s equations. Most magnetic neural probes use a single coil design on silicon substrates; multiple coils using substrate materials with increased pliability may improve these technologies. Here, we discuss the modeling, making, and measuring of multicoil magnetic probes microfabricated on flexible polymer substrates for potential long-term neural stimulation. This novel device design is characterized toward the goal of recording of device-driven action potentials in spatially removed neurons.

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2. S.W. Lee, F. Fallegger, B.D.F. Casse, S.I. Fried, Implantable microcoils for intracortical magnetic stimulation. Sci. Adv. 2, e1600889 (2016).