An Optoelectronics Device to Write-In and Read-Out Activity in Brain Circuits

点击翻译按钮获取中文摘要

1264816Nurmikko, ArtoThe proposed research aims to contribute to the emerging field of neurotechnology by providing a new class of brain "write-in"/ "read-out" devices with unique attributes for bidirectional communication with neural circuits. The project aims to have an impact on both basic neuroscience while providing an important technology piece to future prospects for treating severely neurologically impaired individuals via electronic communications with brain circuits. This is a development project that lies at the very intersection of biomedical engineering and health sciences. More specifically, its aim is to create a new generation of devices that enables the combination of spatially and temporally specific stimulation of and recording from brain circuits in vivo mobile animal models, to advance the understanding of brain function at a fundamental level on one hand, while extrapolating squarely at possible applications e.g. to cases of neurological injury on the other. Extracting information about functional connectivity and performance of neural circuits by electrical recording by arrays of sensing microelectrodes is a well-established and powerful technique. For example, by acquiring resolution at a single neuron level from cortical circuits by implanted multielectrode arrays with real-time decoding the intention of a brain to execute motor action has recently enabled a human tetraplegic patient, with neural signal pathways from the brain to spinal cord inoperative, to control a robotic arm and hand by "thought". Supported further by several powerful demonstrations in non-human primates of brain control, a grand challenge to future neural prostheses is to "close-the-loop" for cortical control of assistive devices, for instance by providing a proxy by brain stimulation for lost sensory capability such as touch. Stimulation by electrical means has been traditionally used to excite the brain across multiple spatial scales for both research and has today specific therapeutic use. Importantly, however, the ability to specifically access well-targeted neural circuits for both excitation and inhibition has been now opened by techniques of "optogenetics", a pioneering new approach in basic and applied brain science and neurotechnology. The optical method offers a much more direct and less ambiguous stimulation of brain circuits to inform brain circuits. To reach this goal, a multielement biomedical implant device is proposed where up to 100 microscale elements are integrally arrayed for dual use - in simultaneously delivering light to and electrically reading out neural circuit dynamics ("100 points of light"). Meeting both fundamental physical and practical physiological challenges, a specific class of so-called wide bandgap crystalline semiconductors is exploited - which have the unusual combinatorial attributes of optical transparency and high electrical conductivity. The proposed device-driven research program leverages directly from expertise in the PIs laboratory where work on development of new neural recording methods (such as by wireless implants) intersects with other research strands where wide-bandgap semiconductors are studied and microfabricated to different types of light-emitting devices. In culmination of the research, the new optical stimulation/electrical read-out capability will be tested and employed in vivo in mobile animal models for fundamental brain science and neurotechnology development purposes.