Many of our daily activities, such as riding a bike to work or reading a book in a noisy cafe, and highly skilled activities, such as a professional playing a tennis match or a violin concerto, depend upon the ability of the brain to quickly make moment-to-moment adjustments to our behavior in response to the results of our actions. Particularly, they depend upon the ability of the neocortex to integrate the information provided by the sensory organs (bottom-up information) with internally generated signals such as expectations or attentional signals (top-down information). This integration occurs in pyramidal cells (PCs) and their long apical dendrite, which branches extensively into a dendritic tuft in layer 1 (L1). The outermost layer of the neocortex, L1 is highly conserved across cortical areas and species. Importantly, L1 is the predominant input layer for top-down information, relayed by a rich, dense mesh of long-range projections that provide signals to the tuft branches of the PCs. Here, we discuss recent progress in our understanding of the composition of L1 and review evidence that L1 processing contributes to functions such as sensory perception, cross-modal integration, controlling states of consciousness, attention, and learning. Expected final online publication date for the Annual Review of Neuroscience, Volume 44 is July 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

中文翻译：

---

新皮质层1：自上而下和自下而上的集成的优雅解决方案。

我们的许多日常活动（例如骑自行车上班或在嘈杂的咖啡馆里读书）以及高技能的活动（例如专业打网球比赛或小提琴协奏曲）都取决于大脑快速做出反应的能力根据我们的行动结果对我们的行为进行瞬间的调整。特别地，它们取决于新皮质将感觉器官提供的信息（自下而上的信息）与内部生成的信号（例如期望或注意信号）（自上而下的信息）整合的能力。这种整合发生在锥体细胞（PC）及其长的顶端树突中，后者在第1层（L1）中广泛分支成树突状簇。新皮层的最外层L1在整个皮层区域和物种中高度保守。重要的，L1是自上而下信息的主要输入层，由丰富而密集的远程投影网格中继，这些投影向PC的簇状分支提供信号。在这里，我们讨论了我们对L1组成的理解的最新进展，并回顾了L1加工有助于诸如感官知觉，跨模式整合，控制意识状态，注意力和学习等功能的证据。《神经科学年度评论》（第44卷）的最终最终在线发布日期为2021年7月。有关修订的估算，请参见http://www.annualreviews.org/page/journal/pubdates。我们讨论了我们对L1组成的理解的最新进展，并回顾了L1加工有助于诸如感官知觉，跨模式整合，控制意识状态，注意力和学习等功能的证据。《神经科学年度评论》（第44卷）的最终最终在线发布日期为2021年7月。有关修订的估算，请参见http://www.annualreviews.org/page/journal/pubdates。我们讨论了我们对L1组成的理解的最新进展，并回顾了L1加工有助于诸如感官知觉，跨模式整合，控制意识状态，注意力和学习等功能的证据。《神经科学年度评论》（第44卷）的最终最终在线发布日期为2021年7月。有关修订的估算，请参见http://www.annualreviews.org/page/journal/pubdates。