Optrode array for optical neural stimulation and recording

光学方法在神经科学、医学成像和诊断等领域正在建立。例如，光遗传学尽管是一个新兴的研究领域，但已被《自然方法》评为2010年年度方法。我们建议开发和测试一种新的设备结构，以促进三维深层组织光的渗透和收集，同时时空调制不同波长的能力，以推进广泛的应用在光学神经刺激和记录。由光学透明针组成的3D光极阵列可以直接穿透1 mm到组织中，从而为光传播创建多个独立的路径，避免由于组织吸收和散射引起的衰减。我们将开发适用于可见光甚至近红外应用的SiO2阵列。这项研究的智力价值在于解决了几乎所有光激发模式的障碍，其中穿透深度由光极长度而不是波长决定。我们建议利用广泛的身体的微加工方法开发的穿透电极，以实现相同的优势，为光学传输和接收相比，外部的方法。更广泛的影响：这项工作可能产生多种广泛的、具有潜在变革性的影响。虽然我们的重点是光遗传神经刺激和记录，但光极阵列器件在基础神经科学研究、高选择性光动力治疗以及用于诊断和治疗的深层组织成像中具有应用。从应用神经科学和神经工程学的角度来看，光极阵列装置将有助于更深入地进入神经组织，例如中枢或外周神经束内的轴突束。在多个刺激/记录部位上更深入的访问可以使神经系统障碍或疾病后失去的运动或感觉功能得以恢复。潜在的代表性应用包括瘫痪后手抓握或站立的恢复，以及肢体丧失后皮肤和本体感觉反馈的恢复。从教育的角度来看，拟议的研究固有的跨学科和互动性质将为生物光子学，微制造，神经工程和基础神经科学的培训提供独特的机会，并将与犹他州大学正在进行的主要研究和教育活动协同互动。从多样性和外展的角度来看，生物工程系（其中PI是一个兼职教师，和共同PI终身教职成员）在吸引和指导女工程师，沿着最近加强学院和大学范围内的推广和招聘工作，建立成功将有助于将代表性不足的人口纳入新兴的神经工程增长领域。

Optical methods are becoming established in the fields of neuroscience, medical imaging and diagnostics, etc. Optogenetics, for example, despite being a nascent field of study, has been named the Method of the Year 2010 by Nature Methods. We propose to develop and test a novel device structure to facilitate three-dimensional deep-tissue light penetration and collection with capabilities for simultaneous spatiotemporal modulation of different wavelenghts to advance a broad range of applications in optical neural stimulation and recording. A 3D optrode array consisting of optically transparent needles can penetrate 1 mm directly into tissue, thereby creating multiple independent paths for light propagation that avoid attenuation due to tissue absorption and scattering. We will develop SiO2 arrays suitable for visible and even NIR applications. The intellectual merits of this research lie in the addressing the barrier for nearly all modes of optical excitation where penetration depth is determined by optrode length, not by wavelength. We propose to leverage off of the extensive body of microfabrication methods developed for penetrating electrodes to achieve the same advantages for optical delivery and reception as compared to external approaches. Broader Impact: Multiple, broadly enabling, and potentially transformative, impacts may emerge from this work. Although our focus is on optogenetic neural stimulation and recording, optrode array devices have application in basic neuroscience research, highly selective photodynamic therapy, and deep tissue imaging for diagnostics and therapy. From an applied neuroscience and neuroengineering perspective, the optrode array device will facilitate deeper access into neural tissue, such as axon bundles within the fasicles of central or peripheral nerves. Deeper access across multiple stimulation/recording sites may enable restoration of lost motor or sensory function after nervous system disorders or disease. Potential representative applications, among many, include restoration of hand grasp or stance after paralysis, and restoration of cutaneous and proprioceptive sensory feedback after limb loss. From an educational perspective, the inherently interdisciplinary and interactive nature of the proposed research will provide unique opportunities for training in biophotonics, microfabrication, neuroengineering, and basic neuroscience, and will interact synergistically with ongoing major research and educational initiatives at the University of Utah. From diversity and outreach perspectives, the established success of the Bioengineering Department (of which the PI is an adjunct-faculty member, and the co-PI a tenure-track member) in attracting and mentoring female engineers, along with recently enhanced College- and University-wide outreach and recruitment efforts, will help bring underrepresented populations into the emerging neuro-engineering growth area.