Collie Matthew F, Jin Chennan, Kellogg Emily, Vanderbeck Quinn X, Hartman Alexandra K, Holtz Stephen L, Wilson Rachel I
bioRxiv. 2025 Apr 26:2025.04.23.650240. doi: 10.1101/2025.04.23.650240.
To pursue an unpredictably moving visual object, the brain must generate motor commands that continuously steer the object to the midline of the visual field via feedback. Behavior implies that visual pursuit relies on a feedback loop with flexible gain, but the mechanisms of this "adaptive control" are not well-understood. Here we show that adaptive control in the pursuit system involves two parallel feedback loops. One serves to steer the object coarsely toward the midline; the properties of this pathway are relatively constant. The other functions to steer the object precisely to the midline, and its properties are flexible: gain increases when the object is moving away from the midline, when the pursuer is running fast, and during arousal. Genetically suppressing this flexible pathway decreases pursuit performance in aroused males. Our findings show how biological feedback systems can implement adaptive control to drive vigorous error correction while avoiding instability.
Parallel pathways detect a visual object in the frontal versus lateral visual fieldSteering arises from combined ipsilateral excitation and contralateral inhibitionThe circuit for frontal objects is direction-selective, for anticipatory steeringThe circuit for frontal objects is also recruited during fast running and arousal.
为了追踪一个不可预测移动的视觉对象，大脑必须通过反馈生成运动指令，将该对象持续引导至视野中线。行为表明视觉追踪依赖于具有灵活增益的反馈回路，但这种“自适应控制”的机制尚未得到充分理解。在这里，我们表明追踪系统中的自适应控制涉及两个并行的反馈回路。一个用于将对象大致引导向中线；该通路的特性相对恒定。另一个功能是将对象精确引导至中线，其特性是灵活的：当对象远离中线、追踪者快速奔跑以及处于唤醒状态时，增益会增加。通过基因抑制这条灵活的通路会降低处于唤醒状态的雄性的追踪性能。我们的研究结果表明生物反馈系统如何能够实施自适应控制以驱动有力的误差校正，同时避免不稳定。
并行通路在额叶与外侧视野中检测视觉对象
转向源于同侧兴奋和对侧抑制的结合
额叶对象的回路具有方向选择性，用于预期转向
在快速奔跑和唤醒期间也会调用额叶对象的回路。
