Title Development of a high-density wireless ECoG device for neuroscience research Project Summary In this Small Business Innovation Research (SBIR) proposal, Cortera Neurotechnologies aims to develop a microsystem for long-term neural activity recording in animal models of neurological disease. Existing neural recording devices require wires for powering and communication, and use penetrating electrode arrays that cause scarring and limit recording longevity to a few months. Our device will record electrocorticographic (ECoG) signals from non-penetrating electrodes placed on the surface of the cortex and relay them wirelessly to an external reader. Today, ECoG arrays are used clinically to localize the seizure focus before epilepsy surgery. Recently, researchers have become increasingly interested in ECoG recordings for neuroscience research since it allows access to recordings from human brains. Commercial ECoG grids enable recordings with spatial resolutions of 2-4mm. We are developing a wireless high-density micrometer-scale ECoG (?ECoG) grid with spatial resolution higher than 500m in order to sample all available information, avoid infection and enable a battery of novel experiments on freely-behaving, untethered subjects. The device we propose takes advantage of recent findings to supersede current state-of the art on three different aspects: 1. The wireless functionality of this system will liberate neuroscientists from the need to perform behavioral experiments on tethered animals, and allow them to work with loosely confined animals enabling novel experiments that benefit from continuous neural recordings and unrestricted animal locomotion. Closure of the surgical site will prevent infections and increase the stability of the neural recordings. Translatd into the clinic, a wireless device will restore patient autonomy in addition to greatly reducing th risk of infection. 2. The use of non-penetrating ECoG electrodes in this system will substantially reduce the amount of scarring and other forms of tissue immune response, providing stable neural signals for multiple years as opposed to the few months of current practice. 3. Our system uses polymer-based micro-fabricated ECoG electrodes that are up to 400 times denser than current state of the art. These electrodes allow researchers to sample neural signals with a spatial resolution comparable to penetrating electrodes, while increasing the longevity by orders of magnitude. The use of a flexible assembly further allows the device to conform to the brain surface. With the advantages highlighted above, we hypothesize that this device can become the new standard instrument for chronic neural recordings in animals and eventually reach applications in the clinical human market.
The wireless ECoG device will have a tremendous impact on the neuroscience research community. The brain activity mapping effort recently announced by the Obama administration has a vision to not only advance the understanding of the brain but to develop the tools required to do functional mapping and treat neurological disorders. This device will enable long-term chronic neural recording from truly freely moving animals and trigger new discoveries in neuroscience. The ability of our proposed technology to produce dense, electrode grids with long-term stability and wireless communication will accelerate the development of this vision by providing a completely new tool for gathering information relevant to neuronal functional mapping since high-density, untethered recordings from the cortical surface are currently unobtainable. The understanding of neuronal activity through functional brain mapping coupled with a minimally- invasive recording instrument will lead to numerous disease therapies such as treatments for epilepsy, Parkinson's disease, Alzheimer's and ALS, as well as to neural prosthetics such as for motor and speech impairments.