Songjiang Hospital and Songjiang Research Institute, Shanghai Key Laboratory of Emotions and Affective Disorders, Shanghai Jiao Tong University School of Medicine, Shanghai, 201600, China.
Department of Anatomy and Physiology, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China.
Nat Commun. 2024 May 27;15(1):4495. doi: 10.1038/s41467-024-48924-8.
Unified visual perception requires integration of bottom-up and top-down inputs in the primary visual cortex (V1), yet the organization of top-down inputs in V1 remains unclear. Here, we used optogenetics-assisted circuit mapping to identify how multiple top-down inputs from higher-order cortical and thalamic areas engage V1 excitatory and inhibitory neurons. Top-down inputs overlap in superficial layers yet segregate in deep layers. Inputs from the medial secondary visual cortex (V2M) and anterior cingulate cortex (ACA) converge on L6 Pyrs, whereas ventrolateral orbitofrontal cortex (ORBvl) and lateral posterior thalamic nucleus (LP) inputs are processed in parallel in Pyr-type-specific subnetworks (Pyr and Pyr) and drive mutual inhibition between them via local interneurons. Our study deepens understanding of the top-down modulation mechanisms of visual processing and establishes that V2M and ACA inputs in L6 employ integrated processing distinct from the parallel processing of LP and ORBvl inputs in L5.
统一的视觉感知需要在初级视皮层（V1）中整合自下而上和自上而下的输入，然而 V1 中自上而下输入的组织仍不清楚。在这里，我们使用光遗传学辅助的回路映射来确定来自更高阶皮层和丘脑区域的多种自上而下的输入如何与 V1 的兴奋性和抑制性神经元相互作用。自上而下的输入在上层重叠，但在深层分离。来自内侧次级视觉皮层（V2M）和前扣带皮层（ACA）的输入汇聚在 L6 锥体神经元上，而腹外侧眶额皮层（ORBvl）和外侧膝状体核（LP）的输入则在锥体神经元特异性子网络（Pyr 和 Pyr）中平行处理，并通过局部中间神经元在它们之间产生相互抑制。我们的研究加深了对视觉处理的自上而下调制机制的理解，并确立了 L6 中的 V2M 和 ACA 输入采用的是与 L5 中 LP 和 ORBvl 输入的并行处理不同的整合处理方式。
