Developing sensory systems must coordinate the growth of neural circuitry spanning from receptors in the peripheral nervous system (PNS) to multilayered networks within the central nervous system (CNS). This breadth presents particular challenges, as nascent processes must navigate across the CNS–PNS boundary and coalesce into a tightly intermingled wiring pattern, thereby enabling reliable integration from the PNS to the CNS and back. In the auditory system, feedforward spiral ganglion neurons (SGNs) from the periphery collect sound information via tonotopically organized connections in the cochlea and transmit this information to the brainstem for processing via the VIII cranial nerve. In turn, feedback olivocochlear neurons (OCNs) housed in the auditory brainstem send projections into the periphery, also through the VIII nerve. OCNs are motor neuron‐like efferent cells that influence auditory processing within the cochlea and protect against noise damage in adult animals. These aligned feedforward and feedback systems develop in parallel, with SGN central axons reaching the developing auditory brainstem around the same time that the OCN axons extend out toward the developing inner ear. Recent findings have begun to unravel the genetic and molecular mechanisms that guide OCN development, from their origins in a generic pool of motor neuron precursors to their specialized roles as modulators of cochlear activity. One recurrent theme is the importance of efferent–afferent interactions, as afferent SGNs guide OCNs to their final locations within the sensory epithelium, and efferent OCNs shape the activity of the developing auditory system.

中文翻译：

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回话：olivocochlear 传出系统的发展。

开发感觉系统必须协调从周围神经系统 (PNS) 中的受体到中枢神经系统 (CNS) 中的多层网络的神经回路的生长。这种广度提出了特殊的挑战，因为新生过程必须跨越 CNS-PNS 边界并合并成紧密混合的布线模式，从而实现从 PNS 到 CNS 的可靠集成并返回。在听觉系统中，来自外围的前馈螺旋神经节神经元 (SGN) 通过耳蜗中以音调局部方式组织的连接收集声音信息，并通过 VIII 颅神经将此信息传输到脑干进行处理。反过来，位于听觉脑干中的反馈橄榄蜗神经元 (OCN) 也会通过 VIII 神经将投射发送到外围。OCN 是运动神经元样传出细胞，可影响耳蜗内的听觉处理并保护成年动物免受噪声损伤。这些对齐的前馈和反馈系统并行发展，SGN 中央轴突到达发育中的听觉脑干，同时 OCN 轴突向发育中的内耳延伸。最近的研究结果已经开始揭示指导 OCN 发展的遗传和分子机制，从它们起源于运动神经元前体的通用库到它们作为耳蜗活动调节剂的特殊作用。一个反复出现的主题是传出-传入相互作用的重要性，因为传入 SGN 将 OCN 引导到它们在感觉上皮细胞内的最终位置，而传出 OCN 塑造正在发育的听觉系统的活动。