The cortex is organized as a hierarchical processing structure. Feedback from higher levels of the hierarchy, known as top-down signals, have been shown to be involved in attentional and contextual modulation of sensory responses. Here we argue that top-down input to the primary visual cortex (V1) from A24b and the adjacent secondary motor cortex (M2) signals a prediction of visual flow based on motor output. A24b/M2 sends a dense and topographically organized projection to V1 that targets most neurons in layer 2/3. By imaging the activity of A24b/M2 axons in V1 of mice learning to navigate a 2D virtual environment, we found that their activity was strongly correlated with locomotion and resulting visual flow feedback in an experience-dependent manner. When mice were trained to navigate a left-right inverted virtual environment, correlations of neural activity with behavior reversed to match visual flow. These findings are consistent with a predictive coding interpretation of visual processing.

中文翻译：

---

鼠标皮质中的感觉运动电路，用于视觉流量预测。

皮质组织为分层处理结构。来自高层层次的反馈（称为自上而下的信号）已显示出与感官反应的注意力和情境调制有关。在这里，我们认为从A24b到主视觉皮层（V1）和相邻的次要运动皮层（M2）的自顶向下输入表示基于运动输出的视觉流预测。A24b / M2向V1发送密集且按地形组织的投影，该投影针对第2/3层中的大多数神经元。通过对学习导航2D虚拟环境的小鼠V1中A24b / M2轴突的活性进行成像，我们发现它们的活性与运动密切相关，并以经验依赖的方式产生了视觉流反馈。当训练小鼠在左右倒立的虚拟环境中导航时，神经活动与行为的相关性反转以匹配视觉流。这些发现与视觉处理的预测编码解释一致。