Sensory control of a motor sequence

摘要 动物从它们的环境中收集感官信息，并使用它在众多信息中进行选择 他们可以执行的行为。准确的神经回路使他们能够检测、比较和 将跨越空间和时间的感觉刺激组合在一起来组织运动序列仍是未知的。 果蝇的梳理行为是一种感觉驱动的运动序列。我们建议使用 光遗传学工具和行为分析来识别相关的感觉神经元和回路 用于启动和推进苍蝇梳理序列。打扮是与生俱来的--基本 修剪的能力是与生俱来的，依赖于基因指定的神经连接，因此 可以通过基因筛查进行解剖。而是构成的行动的顺序 美容是灵活的：很有可能会发生扫头和前腿摩擦 早期和后腿子程序清洁身体后部将在稍后进行，但 这些运动的确切顺序并不是固定的。苍蝇使用更新的感觉线索来修改 扫腿的轨迹，清洁回合的持续时间，以及移动的顺序 有效地将不同的碎屑分布。 对神经系统如何组织可靠但适应性的深入机械性理解 运动序列将解决更大的问题，即动物如何利用洪水般的 感官数据，它们如何平衡运动的需要和运动的需要 根据上下文以及有限数量的神经元如何产生不同的 动物行为。神经回路模体构成了所有神经的基本计算单位 系统。定义完成控制马达的感觉比较的电路 更简单的系统中的序列，如苍蝇梳理，将为理解提供一个模板 如何在所有大脑中实现相似的功能。

Abstract Animals collect sensory information from their environment and use it to select among the many behaviors they can perform. The exact neural circuits that enable them to detect, compare, and combine sensory stimuli across space and time to organize motor sequences remain unknown. Grooming behavior in Drosophila is a sensory-driven motor sequence. We propose to use optogenetic tools and behavioral analysis to identify the sensory neurons and circuits relevant for initiation and progression of the fly grooming sequence. Grooming is innate – the basic capacity to groom is inborn, relying on genetically-specified neural connections, and therefore accessible to dissection by genetic screens. But the sequence of the actions that constitute grooming is flexible: there is a high probability that head sweeps and front leg rubs will occur early and that back leg subroutines to clean the posterior body parts will happen later, but the exact order of these movements is not fixed. Flies use updating sensory cues to modify the trajectory of leg sweeps, the duration of cleaning bouts, and the order of movements to remove different distributions of debris effectively. A deep mechanistic understanding of how the nervous system organizes reliable but adaptive motor sequences will address the larger questions of how animals make use of a flood of sensory data, how they balance the need to exercise a movement precisely with the need to modify it based on context, and how a limited number of neurons produce the diverse array of animal behaviors. Neural circuit motifs form the basic computational units of all nervous systems. Defining the circuits that accomplish sensory comparisons that control a motor sequence in a simpler system such as fly grooming will provide a template for understanding how similar functions are achieved in all brains.