Deploying Intracortical Electrode Arrays to Record and Stimulate in a Tissue Volume

Project Summary The overall goal of this project is to develop a new intracortical electrode array where a flat device is inserted that then deploys microelectrodes at controlled distances within a volume of tissue. This deployable neural interface will overcome two critical limitations associated with recording and stimulation of the cortex: 1) each insertion only leads to placement of electrodes at a point or along a linear path within brain tissue and 2) the recording performance is reduced by adverse tissue response. This work will result in deployable electrode arrays using shape-changing liquid crystal polymer (LCP) substrates with microelectrodes patterned by photolithography. The LCP substrates remain flat during fabrication and processing, then deploy after implantation to predetermined locations that are up to 200 µm away from the implantation site. The central premise of this work is that electrode deployment from a single insertion can enable volumetric placement of microelectrodes in mouse cortex with viable recording and stimulation capability for over four months. The team’s published and preliminary data demonstrate the feasibility of creating deployable electrode arrays using shape-changing liquid crystal polymer (LCP) substrates with microelectrodes patterned by photolithography. To realize this premise, three specific aims are proposed: 1) Fabricate and characterize deployable electrode arrays, 2) Characterize the foreign body response elicited by deploying microelectrode arrays, and 3) Characterize deploying microelectrode arrays by chronic recording and measuring electrochemical performance of the electrodes. The team brings together the necessary expertise in materials and microfabrication (PI Ware) and neural interface design and characterization (Co-I Pancrazio), and histological response to implanted devices (Co-I Capadona).