Ährlund-Richter S, Osako Y, Jenks K R, Odom E, Huang H, Arnold D B, Sur M
The Picower Institute for Learning and Memory, Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA, USA.
Department of Biology, Division of Molecular and Computational Biology, Dornsife College, University of Southern California, Los Angeles, CA, USA.
bioRxiv. 2024 Aug 11:2024.08.06.606894. doi: 10.1101/2024.08.06.606894.
The mammalian Prefrontal Cortex (PFC) has been suggested to modulate sensory information processing across multiple cortical regions via long-range axonal projections. These axonal projections arise from PFC subregions with unique brain-wide connectivity and functional repertoires, which may provide the architecture for modular feedback intended to shape sensory processing. Here, we used axonal tracing, axonal and somatic 2-photon calcium imaging, and chemogenetic manipulations in mice to delineate how projections from the Anterior Cingulate Cortex (ACA) and ventrolateral Orbitofrontal Cortex (ORB) of the PFC modulate sensory processing in the primary Visual Cortex (VISp) across behavioral states. Structurally, we found that ACA and ORB have distinct patterning of projections across both cortical regions and layers. ACA axons in VISp had a stronger representation of visual stimulus information than ORB axons, but both projections showed non-visual, behavior-dependent activity. ACA input to VISp enhanced the encoding of visual stimuli by VISp neurons, and modulation of visual responses scaled with arousal. On the other hand, ORB input shaped movement and arousal related modulation of VISp visual responses, but specifically reduced the encoding of high-contrast visual stimuli. Thus, ACA and ORB feedback have separable projection patterns and encode distinct visual and behavioral information, putatively providing the substrate for their unique effects on visual representations and behavioral modulation in VISp. Our results offer a refined model of cortical hierarchy and its impact on sensory information processing, whereby distinct as opposed to generalized properties of PFC projections contribute to VISp activity during discrete behavioral states.
哺乳动物的前额叶皮质(PFC)被认为可通过长距离轴突投射调节多个皮质区域的感觉信息处理。这些轴突投射起源于具有独特全脑连接性和功能组合的PFC子区域,这可能为旨在塑造感觉处理的模块化反馈提供架构。在这里,我们使用轴突追踪、轴突和体细胞双光子钙成像以及对小鼠进行化学遗传学操作,来描绘PFC的前扣带皮质(ACA)和腹外侧眶额皮质(ORB)的投射如何在不同行为状态下调节初级视觉皮质(VISp)中的感觉处理。在结构上,我们发现ACA和ORB在皮质区域和层中具有不同的投射模式。VISp中的ACA轴突比ORB轴突对视觉刺激信息的表征更强,但两种投射都表现出非视觉的、依赖行为的活动。ACA对VISp的输入增强了VISp神经元对视觉刺激的编码,并且视觉反应的调节随觉醒程度而变化。另一方面,ORB输入塑造了VISp视觉反应中与运动和觉醒相关的调节,但特别减少了对高对比度视觉刺激的编码。因此,ACA和ORB反馈具有可分离的投射模式,并编码不同的视觉和行为信息,推测这为它们对VISp中的视觉表征和行为调节产生独特影响提供了基础。我们的结果提供了一个关于皮质层级及其对感觉信息处理影响的精细模型,据此PFC投射的独特而非一般特性在离散行为状态期间有助于VISp的活动。