An advanced surgical microscope for novel studies of sensorimotor integration for flight control

大脑的一个关键作用是合成控制运动的感觉信息。大多数神经科学研究都是在有限的准备中进行的，这给我们对自由运动所需的复杂运动的控制的理解留下了很大的空白。机动性对生存至关重要，也容易受到疾病、损伤和衰老的影响。我的实验室小组使用蜂鸟和斑胸草雀作为研究模型，因为它们明确的视觉通路和极其灵活的飞行可以在实验环境中进行研究。我们现在正在使用新技术来研究自由飞行的鸟类的大脑，这在以前是不可能的。然而，我们缺少一种必不可少的设备，即现代手术显微镜。

A key role of the brain is to synthesize sensory information for the control of movement. Most neuroscience research occurs in restricted preparations, which leaves a major gap in our understanding of the control of complex motions required for free movement. Maneuverability is critical for survival, and susceptible to disease, injury, and ageing. My laboratory group uses hummingbirds and zebra finches as research models because their well-defined visual pathways and extremely maneuverable flight can be studied in an experimental setting. We are now using new technologies to study the brain in freely flying birds, something which was not previously possible. However, we lack one essential piece of equipment, a modern surgical microscope. In recent studies, my group investigated how visual signals are processed in the brain and transformed into motor commands for fundamental control tasks including velocity, centering, decelerating, obstacle avoidance, group behaviour (flocking), and holding station (hovering). Through a previous RTI grant, we developed an integrated flight arena that includes automated flight tracking of 3D trajectories, real-time closed-loop visual stimulus presentation, and a moving track that allows electronics to travel with the flying bird for simultaneous electrophysiological recording and optogenetic activation. There is no other laboratory in the world with these capabilities. A significant challenge to our work is that there are no modern surgical microscopes available in our building or department. The two available scopes date from the middle of the last century and have poor optical resolution, lighting, and control. The ability to make chronic implants for employing tetrode recordings and optogenetic stimulation requires a state-of-the-art surgical microscope that has four essential features: 1) high resolution optics over an extended depth of field, 2) directed light sources for optical resolution in deep cavities, 3) hands-free optical control, and 4) stable positioning and flexible 6-axis maneuverability to cope with the movement of wires, cables, and visual monitors around an animal subject. To facilitate the efficient transmission of skill for expertise to HQP, the scope also requires video recording and display, and an assistant's objective. A modern surgical scope will allow for investigation of the neural circuits that control complex locomotion, research that is not otherwise possible. Three specific questions that will guide this work are: a) how do solitary versus social flyers encode the motion of other birds, whether in the object motion visual pathway or in the optic flow visual pathway?; b) how do the major optic flow nuclei contribute to the encoding of distinct guidance algorithms for forward motion?; c) are distinct guidance algorithms between hovering and forward flight mediated by efference copy suppression of optic flow signals?