Visual-spatial processing within the retrosplenial cortex

了解我们的空间环境以及如何在这些环境中导航对所有物种都至关重要。了解我们的大脑如何支持这些过程是神经科学的长期目标。这一目标正变得越来越重要，因为空间处理对正常衰老和病理性衰老（如阿尔茨海默病）都特别敏感。脾后皮层在处理环境信息方面显得尤为重要。最近的一项研究使用体内成像技术（双光子成像）来识别动物学习空间记忆任务时神经元活动的模式；训练结束时更稳定的表征与动物完成任务的好坏有关。脾后皮层也含有对视觉刺激和运动作出反应的细胞。在神经元水平上结合视觉空间和运动信息可能对脾后皮层在导航中的作用至关重要。该项目将以这些先前的发现为基础，试图在网络水平上理解这些空间表征是如何在脾后皮层形成的。一个重要的问题是，与其他大脑区域（如海马体和视觉皮层）的联系如何帮助这些表征的发展，以及这些大脑结构之间的相互作用如何从一个新的环境到一个熟悉的环境发生变化。该项目的目标将通过结合体内神经元成像和体内电生理学的行为来实现。此外，化学遗传学和光遗传学方法将提供一种暂时灭活或刺激网络内不同通路的方法，以确定功能丧失或获得的影响。总之，这将有助于确定与支撑空间相关表征的获取和保留的脾后皮层相关的特定神经元通路。

Learning about our spatial environments and how to navigate within these environments is critical for all species. It is a long-standing goal of neuroscience to understand how our brains support these processes. This goal is becoming ever more important as it has become apparent that spatial processing is particularly sensitive to both normal ageing and pathological ageing, such as Alzheimer's disease. The retrosplenial cortex appears to be particularly important for processing information about our environments. A recent study used an in vivo imaging technique (two-photon imaging) to identify patterns of neuronal activity that developed as animals learnt a spatial memory task; the more stable representations at the end of training were related to how well the animals performed the task. The retrosplenial cortex also contains cells that respond to visual stimuli and the movement. Combining visual-spatial and movement information at a neuronal level could be critical for the retrosplenial cortex's role in navigation. This project will build on these previous findings to try and understand, at a network level, how these spatial representations within the retrosplenial cortex are formed. An important question is how connections with other brain regions such as the hippocampus and visual cortex help these representations to develop and how the interaction across these brain structures changes from when an environment is new to when it has become familiar and well-learnt. The goals of the project will be achieved using a combining behaviour with in vivo neuronal imaging and in vivo electrophysiology. In addition, chemogenetic and optogenetic approaches would provide a means to temporarily inactivate or stimulate different pathways within the network to determine the effects of loss or gain of function. Together, this will help identify specific neuronal pathways related to the retrosplenial cortex that underpin the acquisition and retention of spatially-related representations.