Neurophotonic-electronic brain-machine interface system

大脑映射和解锁大脑电路，可以为诊断和治疗从帕金森病和阿尔茨海默病到精神疾病的大脑疾病提供令人难以置信的机会。这一直是科学界努力的驱动力，并导致了大脑研究方法的几项突破性创新（例如：光遗传学、连接组学、磁共振成像、用于模拟大脑的超级计算机等）。这些方法中的每一种都面临着技术或根本性的挑战。因此，大脑中数十亿神经元网络的完整映射仍然是一个挑战。我们正在开发一种电子-光子脑机接口系统，用于同时对大脑皮层进行光学刺激沿着对神经元进行电记录。我们的系统由微激光器和光可切换的石墨烯基电极组成。微激光器被设计成类似于生物神经元，并以高时间分辨率和微米级空间分辨率的光脉冲形式发射尖峰。这些光脉冲会打开皮层上的石墨烯电极，为神经元刺激提供所需的电压。为了调制微激光器，我们需要一个任意波形发生器（AWG）。AWG可以高速输出用户定义的任意形状的波形，可以模拟真实世界的信号（例如，spikes）。电极必须与大脑皮层的复杂拓扑结构超共形，以实现对神经元的稳定刺激和记录。因此，电极的基底必须是超薄的、透光的和生物相容的。Parylene是唯一能够满足这些要求的聚合物。我们正在申请聚对二甲苯沉积系统（即。涂布机）来制造用于制造光可切换石墨烯电极的衬底。** 该设备将支持我们的合作和跨学科研究计划，以及我们在三个部门（工程物理，电气工程，神经科学）以及我们的合作者的10+ HQP（化学工程，化学）作为NSERC CREATE-MAPS计划的一部分，每天访问我们的实验室设备（如电子束蒸发器）。争取多样性，包括平衡的性别代表性，包容性和代表性不足的群体的进步，我们的团队由一名女博士后（委内瑞拉），3名女研究生和5名女本科生，以及2名来自代表性不足的少数民族的研究生组成。通过生物和人工微激光神经元之间的双向通信，所提出的系统能够将大脑中复杂的未知神经元网络复制到芯片上的已知硬件组件网络。复制的网络可以用来解锁大脑的通信模式。如果大规模成功，这种大脑绘图技术可用于研究影响全球10亿人的神经系统疾病。

Brain mapping and unlocking the brain circuitry, can open incredible opportunities for the diagnosis and treatment of brain disorders from Parkinson and Alzheimer's disease to mental disorders. This has been the driving force of the scientific community's effort and has resulted in several ground-breaking innovations in brain study methods (eg. optogenetics, connectomics, magnetic resonance imaging, supercomputers for simulating the brain etc.). Each of these approaches faces either technological or fundamental challenges. As such, a complete mapping of the networks of billions of neurons in the brain remains a challenge.******We are developing an electronic-photonic brain-machine interface system for simultaneous optical stimulation of the brain cortex along with electrical recording of neurons. Our system is composed of microlasers and light-switchable graphene-based electrodes. The microlasers are engineered to be analogous to biological neurons and emit spikes' as light pulses with high temporal resolution and micron-scale spatial resolution. These light spikes switch on the graphene-based electrodes on the cortex to deliver the required electric voltage for neurons stimulation.******For modulating the microlasers, we are requesting an arbitrary waveform generator (AWG). An AWG can output user-defined arbitrary shape waveforms at high speeds that can mimic real-world signals (eg. spikes). The electrodes must be ultra-conformal to the complex topology of the brain's cortex to enable stable stimulation and recording of the neurons. Therefore, the electrodes' substrate must be ultra-thin, transparent to light, and biocompatible. Parylene is the only polymer that can satisfy these requirements. We are requesting a parylene deposition system (ie. a coater) to make the substrates for fabricating the light-switchable graphene electrodes. ******This equipment will support our collaborative and interdisciplinary research program, and the training of our 19 HQP across three departments (eng. physics, electrical eng., neuroscience) in addition to 10+ HQP of our collaborators (chemical eng., chemistry) as part of the NSERC CREATE-MAPS program who access our lab equipment (such as e-beam evaporator) on a daily basis. Striving for diversity including balanced gender representation, inclusivity and advancement of under-represented groups, our team consists of a female postdoc (Venezuela), 3 female graduate and 5 female undergrad students, and 2 graduate students from underrepresented minority.******Enabled by the bidirectional communication between the biological and artificial microlaser neurons, the proposed system is capable of copying' a complex unknown network of neurons in the brain to a known network of hardware components on a chip. The copied network can be used to unlock the communication patterns of the brain. If successful on a large-scale, such a brain mapping technique could be used to study neurological disorders that affect 1 billion people globally.