Department of Biomedical Engineering, The University of Arizona, Tucson, AZ 85721.
Department of Neurobiology, Northwestern University, Evanston, IL 60201.
Proc Natl Acad Sci U S A. 2021 Jul 27;118(30). doi: 10.1073/pnas.2025775118.
Wireless, battery-free, and fully subdermally implantable optogenetic tools are poised to transform neurobiological research in freely moving animals. Current-generation wireless devices are sufficiently small, thin, and light for subdermal implantation, offering some advantages over tethered methods for naturalistic behavior. Yet current devices using wireless power delivery require invasive stimulus delivery, penetrating the skull and disrupting the blood-brain barrier. This can cause tissue displacement, neuronal damage, and scarring. Power delivery constraints also sharply curtail operational arena size. Here, we implement highly miniaturized, capacitive power storage on the platform of wireless subdermal implants. With approaches to digitally manage power delivery to optoelectronic components, we enable two classes of applications: transcranial optogenetic activation millimeters into the brain (validated using motor cortex stimulation to induce turning behaviors) and wireless optogenetics in arenas of more than 1 m in size. This methodology allows for previously impossible behavioral experiments leveraging the modern optogenetic toolkit.
无线、无电池、完全可皮下植入的光遗传学工具有望彻底改变在自由活动动物中进行的神经生物学研究。新一代的无线设备足够小、薄且轻，可用于皮下植入，与用于自然行为的有线方法相比具有一些优势。然而，当前使用无线功率传输的设备需要进行侵入性的刺激传递，穿透颅骨并破坏血脑屏障。这可能导致组织移位、神经元损伤和瘢痕形成。功率传输限制还极大地限制了操作范围的大小。在这里，我们在无线皮下植入物的平台上实现了高度微型化的电容式储能。通过采用数字方式管理光电组件的功率传输，我们能够实现两类应用：颅外光遗传学刺激大脑深处（通过刺激运动皮层来诱导转向行为进行验证）以及 1 米以上大小的无线光遗传学。这种方法允许利用现代光遗传学工具包进行以前不可能的行为实验。
