NCS-FO: A circuit theory of cortical function

该项目旨在开发和测试一个新的概念框架，以了解大脑功能，并为基于生物的人工智能系统提供信息。基本理论认为，任何神经元和任何皮质区域的性质都不是固定的，而是随着知觉任务、预期和注意的变化而经历状态变化。由于这种自上而下的信息可以通过多种途径传递，每个神经元本质上都是整个大脑的一个缩影。在这个框架中，神经元被视为自适应处理器，而不仅仅是标签行中的一个链接，承担着执行当前任务所需的功能。这一理论解释了电路水平上的皮质功能。通过反馈和内在联系之间的相互作用，神经元选择与任务相关的输入，并抑制不相关的输入。这些实验将结合视觉心理物理学、功能磁共振成像、大规模高密度电极阵列记录和光遗传操作。这些技术将被用来测量皮质区域之间的有效连通性的变化，以及当动物执行不同的视觉识别任务时，有效连通性与不同记录位置的神经元所代表的信息之间的关系。将开发计算模型来解释如何实现依赖于任务的连接选通，并将重现实验观察到的功能动力学。虽然这些实验将集中在视觉通道上，但这项工作的发现将形成一个广泛适用于整个大脑的大脑功能一般理论。

This project aims to develop and test a new conceptual framework for understanding brain function, and informing biologically based artificial intelligence systems. The underlying theory holds that the properties of any neuron and any cortical area are not fixed but undergo state changes with changing perceptual task, expectation and attention. Because of the multiple routes by which this top-down information can be conveyed, each neuron is essentially a microcosm of the brain as a whole. In this framework, a neuron is viewed as an adaptive processor rather than merely a link in a labeled line, taking on functions that are required for performing the current task. The theory accounts for cortical function at the circuit level. Through an interaction between feedback and intrinsic connections neurons select inputs that are relevant to a task and suppress inputs that are irrelevant. The experiments will combine visual psychophysics, fMRI, large scale high density electrode array recordings and optogenetic manipulation. These techniques will be used to measure changes in effective connectivity between cortical areas and the relationship between effective connectivity and the information represented by neurons at different recording sites as animals perform different visual recognition tasks. Computational models will be developed to account for how task-dependent gating of connections can be achieved and will reproduce the functional dynamics observed experimentally. Though the experiments will focus on the visual modality, the findings from the work will formulate a general theory of brain function that is broadly applicable to the brain as a whole.