Implantable, Wireless, and Power-Efficient Trimodal Neural Interface for Electro-Optogenetic Manipulation of Visual Cortex in Small Freely Behaving Animals
Award Goal This proposal aims to realize an integrated, wireless, trimodal opto-electro neural interface to tackle the critical challenge of high-resolution spatiotemporal mapping and closed-loop control of visual cortex, which will enable better understanding of the structure and function of brain networks during visual processing of small, freely behaving animals.
Blindness has affected millions of people worldwide, and at present is incurable. A cortically-based visual prosthesis is believed to provide a therapeutic solution for all causes of blindness. However, restoration of visual senses to a useful level has not yet been achieved with cortical implants, mainly due to the complex organization of visual cortex and visual preprocessing in the retina and the lateral geniculate nucleus. Therefore, the objective of this proposal is to realize a novel neural interface for high-resolution stimulation and recording of neural activity in visual cortex, which will enable better understanding of the structure and function of neural networks during visual processing. The proposed technology development of this research will yield novel and enabling tools for seamless communication with brain networks of small animals, by which neuroscientists could significantly move fundamental neuroscience knowledge forward. The developed ultra-low-power microelectronics and advanced microfabrication techniques can be applicable to other implantable devices and biomedical systems. In addition, the proposed project will offer unique training opportunities for students at multiple levels. Integrated outreach activities will effectively convert state-of-the-art science and technologies into educational resources accessible to local K-12 schools and communities. To reach broader audiences, the results will be disseminated through science fairs, publication, workshops and conferences.
As the core of this proposal, a wireless, trimodal neural interface will be developed to form the most comprehensive interface with the central nervous system of awake, freely behaving animal subjects. In particular, a multichannel opto-electro array will incorporate epidural light emitting diodes, intracortical microscale waveguide, and microelectrodes in a single platform, capable of optogenetic/electrical stimulation and electrical recording of neural activity of specific cell populations. Implantable, ultra-low-power microelectronic system-on-a-chip will be able to receive and process neural recording data and drive the optical/electrical neural stimulating array. Wireless telemetry links will be implemented to transfer power and data efficiently between the external data-acquisition/control units and implanted neural interface. These key components will be integrated on a mechanically flexible substrate and encapsulated by a hybrid biopolymer package. The integrated wireless neural interface will be implanted and characterized in the primary visual cortex of anesthetized and freely behaving rats, in order to validate its efficacy for wireless neural recording and stimulation. The proposed research activities will be conducted by a collaborative team with complementary research expertise in the areas of bioMEMS, microelectronics, and neurophysiology. Achievement of the goals of this research will pave the road towards the development of a fully functional, cortically-based visual neuroprosthetic system capable of generating artificial vision for completely blind individuals. While the proposal is specifically tailored for studying the visual function of the brain, the developed technologies can also be used for functional mapping and controlling of other regions of the brain and nervous system, particularly those related to motor functions (e.g. spinal cord and peripheral nervous systems).
