Sensory control of a motor sequence

摘要 动物从它们的环境中收集感官信息，并利用这些信息在众多环境中进行选择。 他们可以执行的行为。精确的神经回路使他们能够检测，比较， 联合收割机的感觉刺激跨越空间和时间来组织运动序列仍然是未知的。 果蝇的理毛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，以确定相关的感觉神经元和回路 用于启动和进行苍蝇梳理序列。理毛是与生俱来的-- 梳理毛发的能力是与生俱来的，依赖于基因指定的神经连接，因此， 可以通过基因筛选进行解剖。但构成这些行为的顺序 梳理是灵活的：有很高的可能性，头部扫和前腿摩擦将发生 早期和后腿子程序，以清洁后身体部分将发生后，但 这些运动的确切顺序并不固定。苍蝇使用更新的感官线索来修改 腿扫的轨迹，清洁回合的持续时间，以及移动的顺序，以消除 不同的碎片分布。 对神经系统如何组织的深刻机械理解可靠但适应性强 运动序列将解决更大的问题，动物如何利用洪水， 感官数据，他们如何平衡需要行使运动精确与需要， 根据上下文修改它，以及有限数量的神经元如何产生各种各样的神经元。 动物行为。神经回路基序构成了所有神经系统的基本计算单元。 系统.定义完成控制运动的感觉比较的电路 一个简单的系统中的序列，如苍蝇梳理，将提供一个模板， 所有的大脑是如何实现相似的功能的

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.