Neuronal cell-types are arranged in brain-wide circuits to guide behavior. In mice, the superior colliculus is comprised of a set of cell-types that each innervate distinct downstream targets. Here we reveal the brain-wide networks downstream of four collicular cell-types by combining functional ultrasound imaging (fUSi) with optogenetics to monitor neural activity at a resolution of ~100 μm. Each neuronal group triggered different behaviors, and activated distinct, partially overlapping sets of brain nuclei. This included regions not previously thought to mediate defensive behaviors, e.g. the posterior paralaminar nuclei of the thalamus (PPnT), that we show to play a role in suppressing habituation. Electrophysiological recordings support the fUSi findings and show that neurons in the downstream nuclei preferentially respond to innately threatening visual stimuli. This work provides insight into the functional organization of the networks governing defensive behaviors and demonstrates an experimental approach to explore the whole-brain neuronal activity downstream of targeted cell-types

中文翻译：

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神经活动介导胶质依赖行为的全脑图

神经元细胞类型排列在全脑电路中以指导行为。在小鼠中，上丘由一组细胞类型组成，每种类型都可支配不同的下游靶标。在这里，我们将功能超声成像（fUSi）与光遗传学相结合，以约100μm的分辨率监测神经活动，从而揭示了四种胶体细胞类型下游的全脑网络。每个神经元组触发不同的行为，并激活不同的，部分重叠的脑核集。这包括以前没有被认为可以介导防御行为的区域，例如丘脑的后椎板旁核（PPnT），我们证明其在抑制习惯性中发挥了作用。电生理记录支持fUSi的发现，并显示下游核中的神经元优先响应先天性威胁的视觉刺激。这项工作提供了对管理防御行为的网络的功能组织的见解，并展示了一种探索目标细胞类型下游全脑神经元活动的实验方法。