This work is directed at the development of a microelectrode array for electrocorticography (ECoG) that allows the recording and stimulation of neural activity on the surface of the brain over a large area at high spatial resolution. Existig technologies either allow the recording of neural activity (i) over a large brain area at low spatil resolution (standard commercial ECoGs), or (ii) over a small brain area at high spatial resolution (so called µECoGs). BMSEED aims to produce large-area-high-resolution µECoG electrode arrays (lahrµECoGs). Conventional ECoG electrode arrays are placed on the surface of the brain, and are used as a less invasive alternative to penetrating microelectrodes, which are inserted into the brain tissue. They are used (i) in neuroscience research to explore the fundamentals of how the brain operates, (ii) in brain-machine-interfaces (BMIs) to record neural activity to drive a neuroprosthesis for amputees or to move a computer cursor for the paralyzed, and (iii) for monitoring neural activity during epilepsy surgery to identify the regions of the corex that generate seizures, which subsequently are removed. These applications would benefit from BMSEED's lahrµECoG because it would provide more accurate localization of the recorded signals (i.e., normal neural activity as well as seizures) over a large area, thus improving brain research, making BMIs more robust, and improving clinical outcomes in epilepsy surgery by providing the neurosurgeon with more accurate localization of seizure activity. In all ECOGs, each recording electrode requires one wire to electrically connect to the data acquisition system without intersecting (i.e., without shorting) with other wires. This becomes increasingly difficult as the density and total number of electrodes increases. BMSEED's lahrµECoG solves this problem by routing the lead wires on multiple levels. In addition, our proprietary technology to produce mechanically robust microelectrodes using microfabrication techniques allows us to reduce the thickness, thus the stiffness, of the device, making the implant more compliant. Importantly, BMSEED's lahrµECoG consists entirely of materials that are suitable for implantation in humans, thus simplifying the FDA approval process. The first specific aim is to optimize the profile of the slope between different levels to provide a reliable electrical connection, and to fabricate and electromechanically characterize prototypes of the lahrµECoG. The second aim is to demonstrate the biocompatibility and capabilities of the prototypes. To that end, a lahrµECoG will be chronically implanted in five cats, and neural recording and micro-stimulation data will be obtained for at least two months. At the end of phase I, BMSEED will have (i) developed the capability to produce multi-level metallization and prototypes of lahrµECoGs, and (ii) characterized their capabilities in a cat model. In phase II, BMSEED will extend the lahrµECoGs development to multi-level metallization on larger, clinically relevant substrate sizes. Our customers will initially be research laboratories, and, after FDA approval, biomedical companies for BMI applications and hospitals for clinical applications.
Public Health Relevance Statement: Public Health Relevance: This work proposes the development of a microelectrode array for electrocorticography (ECoG) that allows the recording and stimulation of neural activity over a large area of the brain at a high spatial resolution. This tool will provide improved methods for research on how the brain operates, improve brain-machine-interfaces (BMI) to aid amputees and the paralyzed, and improve clinical outcomes in epilepsy surgery by providing the neurosurgeon more accurate information about the location of seizure activity.
NIH Spending Category: Assistive Technology; Bioengineering; Brain Disorders; Epilepsy; Neurodegenerative; Neurosciences; Rehabilitation
Project Terms: Amputees; Animals; Area; awake; biomaterial compatibility; Brain; brain machine interface; brain research; brain tissue; Caliber; Clinical; clinical application; clinically relevant; Computers; Custom; Data; data acquisition; density; design; Development; Devices; Dose; Eastern Cooperative Oncology Group; electric impedance; Electrocorticogram; Electrodes; Electrophysiology (science); Encapsulated; Epilepsy; Evaluation; Family Felidae; Felis catus; Film; Goals; Gold; Hospitals; Human; Implant; implantation; improved; in vivo; Laboratory Research; Lead; Location; Measures; Mediating; Microelectrodes; Microfabrication; Modeling; Monitor; Movement; nanoparticle; neural stimulation; neuroprosthesis; Neurosciences Research; Neurosurgeon; neurotransmission; Operative Surgical Procedures; Outcome; Paralysed; Phase; Platinum; Polychlorinated Biphenyls; prevent; Problem Solving; Process; Property; prototype; public health relevance; relating to nervous system; Research Methodology; resistant strain; Resolution; response; Route; Rupture; Seizures; Signal Transduction; Silicones; Site; Small Business Innovation Research Grant; Stretching; Surface; System; Techniques; Technology; Temperature; Testing; Thick; Time; Titania; Titanium; tool; Utah; Work
