Institute of Behavioural Neuroscience, University College London, London, United Kingdom.
Front Neural Circuits. 2022 Apr 29;16:792959. doi: 10.3389/fncir.2022.792959. eCollection 2022.
The superior colliculus (SC) is a highly conserved area of the mammalian midbrain that is widely implicated in the organisation and control of behaviour. SC receives input from a large number of brain areas, and provides outputs to a large number of areas. The convergence and divergence of anatomical connections with different areas and systems provides challenges for understanding how SC contributes to behaviour. Recent work in mouse has provided large anatomical datasets, and a wealth of new data from experiments that identify and manipulate different cells within SC, and their inputs and outputs, during simple behaviours. These data offer an opportunity to better understand the roles that SC plays in these behaviours. However, some of the observations appear, at first sight, to be contradictory. Here we review this recent work and hypothesise a simple framework which can capture the observations, that requires only a small change to previous models. Specifically, the functional organisation of SC can be explained by supposing that three largely distinct circuits support three largely distinct classes of simple behaviours-arrest, turning towards, and the triggering of escape or capture. These behaviours are hypothesised to be supported by the optic, intermediate and deep layers, respectively.
上丘（SC）是哺乳动物中脑高度保守的区域，广泛参与行为的组织和控制。SC 接收来自大量脑区的输入，并向大量脑区提供输出。与不同区域和系统的解剖连接的汇聚和发散为理解 SC 如何促进行为带来了挑战。最近在小鼠中的研究提供了大量的解剖数据集，以及大量的新数据，这些数据来自于在简单行为期间识别和操纵 SC 内不同细胞及其输入和输出的实验。这些数据为更好地理解 SC 在这些行为中的作用提供了机会。然而，一些观察结果乍一看似乎相互矛盾。在这里，我们回顾了最近的这些研究工作，并提出了一个简单的框架，可以解释这些观察结果，而只需要对以前的模型进行很小的修改。具体来说，可以假设三个主要不同的回路分别支持三种主要不同的简单行为——静止、转向和触发逃跑或捕获，来解释 SC 的功能组织。这些行为分别被假设为由视顶盖、中间层和深层支持。
