Ferromagnetic Fiber Systems for Multiplexing Neural Recording and Modulation with Spatial Selectivity

Despite the great success achieved by recently developed neural interfaces, multi-site monitoring and regulating neural activities with high spatial and temporal selectivity remain a challenge. Here, an implantable, remotely controllable, fiber-based ferromagnetic system permitting 3D navigation, omnidirectional steering, multiplexing neural recording, and modulation is presented. A family of fibers is fabricated that allows for the heterogeneous integration of ferromagnetic, optical, microfluidic, electrical, and electrochemical components into the proposed multifunctional neural interface. Coupling with magnetic actuation, it is demonstrated that this system can enable optical and chemical modulation of local neural activities across multiple distant regions in rodent brains, while simultaneously allowing the real-time monitoring of neural electrophysiological and chemical activities. Furthermore, to systematically identify altered patterns of behaviors, brain activities and dopamine release during optogenetic modulation of specific nuclei in Parkinsonian animals this platform is employed. This proposed system with high spatial selectivity, multiplexing sensing and multimodal manipulating capabilities offers a versatile platform to advance both fundamental neuroscience studies and translational applications in neurologic disease treatments. © 2024 Wiley-VCH GmbH.