Advanced three-dimensional microscale electrode array for high-density volumetric neural interfacing

Project Summary/AbstractSystems neuroscience is powered by progressively more sophisticated microscale neural probe technologies. Decoding the complex neural circuits underlying memory, behavior and perception often requires, in part, recording from as many neurons as possible in targeted brain regions with high spatial and temporal precision and over multiple spatial and temporal scales. While advances in neural probe technologies over the last 10 years have led to impressive gains in neural interfacing capabilities, current technologies are up against fundamental limitations in three critical aspects: (i) optimized electrode site density with minimized tissue displacement, (ii) sufficiently sampling a prescribed brain volume via precise positioning of sites with the tissue volume, and (iii) recording reliable and stable neuronal activity over time scales of minutes to months.The overall goal is to develop and commercialize an innovative neural probe platform technology that pushes well beyond current neural interfacing limits in these aspects. The proposed “G3” platform technology will achieve order-of-magnitude improvements in probe size, electrode site density and count, three-dimensional site layouts, and recording longevity. The fully elaborated array will be a 4096-site intracortical array with a precise three- dimensional layout of sites that is custom fit to the target region. The G3 platform technology is innovative through the use of advanced implant materials, the development of a sophisticated microfabrication and assembly process, and the significant expansion of the neural interfacing design space to enable new neuroscience discovery.The specific goals of this SBIR Phase I project are to develop the G3 platform technology and to prototype and test several reference designs. Specific Aim 1 of the Phase I project will develop the microfabrication process for the G3 platform technology. Resulting G3 probes will be 5-µm thick, and each 20-µm wide shank will have electrode sites on both sides of the planar substrate. Specific Aim 2 will develop micro-assembly techniques to make and validate three-dimensional arrays of G3 probes. The most advanced Phase I device will be a three-dimensional 1024-site array consisting of four planar probes each having four penetrating shanks. Phase I probes will undergo quantitative electrical and mechanical bench-level testing to evaluate feasibility and refine the designs and manufacturing processes to meet specific functional requirements.Project NarrativeSystems neuroscience is powered by progressively more sophisticated microscale neural probe technologies; however, current technologies are up against fundamental limitations related to size, site positioning in the tissue volume, and long-term recording reliability. The overall goal of this project is to develop and commercialize an innovative neural probe platform technology that pushes well beyond current neural interfacing limits and provides order-of-magnitude improvements in probe size, electrode site density and count, three-dimensional site layouts, and recording longevity. The platform technology will enable multiple product families that will serve the global neuroscience research market and may also be applicable to highly specific clinical markets.