Sensory-motor strategies for odor-guided navigation

项目摘要 动物通过动态的、迭代的感觉-运动过程与世界互动，这些过程引导他们的 正在进行的运动。气味导航是基本自然行为的基础，如 寻找食物来源，但对告知适应性的感觉信号的性质知之甚少 运动的变化。在这里，我们建议测试分布式活动如何对空间信息进行编码 以及这种信息是如何被更高阶的大脑区域解码的。嗅觉采样 通过嗅觉发生--离散的感官样本被认为提供了当前气味的快照 环境。一种可能性是动物通过比较强度来提升浓度梯度。 在接二连三的气味中。另一种是方向信息可能以左至右“立体声”的形式呈现 两个半球之间的比较。为了解决这个问题，我们使用新的成像工具来可视化大型- 气味引导搜索小鼠双侧嗅球的尺度活动动力学。 我们还描述了解码该空间的下游电路中的函数计算 信息，使用全细胞记录和光遗传刺激建立双边规则 突触整合，以及高分辨率在体光刺激标测，以测量交叉 完整电路中的半球相互作用。最后，我们使用光遗传活动操控 气味引导搜索以测试交叉嗅觉与左右立体声比较在快速驾驶中的因果作用 机动调整。总之，这些数据将有助于建立感觉-运动算法 是关键的行为学行为的基础，并为更广泛地探索动物是如何 利用感官线索在复杂的自然环境中导航。

Project Summary Animals interact with the world through dynamic, iterative sensory-motor processes that guide their ongoing movement. Odor-guided navigation is the basis for fundamental natural behaviors such as finding food sources, but little is known about the nature of the sensory signals that inform adaptive changes in locomotion. Here we propose to test how spatial information is encoded by distributed activity in the olfactory bulb, and how this information is decoded by higher-order brain areas. Olfactory sampling occurs through ‘sniffs’ – discrete sensory samples thought to provide a snapshot of the current odor environment. One possibility is that animals ascend concentration gradients by comparing intensity across successive sniffs. Another is that directional information may be present in left-right ‘stereo’ comparisons between hemispheres. To address this issue, we use new imaging tools to visualize large- scale activity dynamics over both hemispheres of olfactory bulb in mice engaged in odor-guided search. We also characterize functional computations in the downstream circuits that decode this spatial information, using whole cell recordings and optogenetic stimulation to establish rules for bilateral synaptic integration, as well as high-resolution in vivo photostimulation mapping to measure cross- hemisphere interactions in the intact circuit. Finally, we use optogenetic activity manipulations during odor-guided search to test the causal role of cross-sniff vs. left-right ‘stereo’ comparisons in driving rapid locomotor adjustments. Together, these data will help establish the sensory-motor algorithms that underlie a key ethological behavior, and provide a foundation for a wider exploration of how animals exploit sensory cues to navigate complex natural environments.