SFB 1134: Functional ensembles: cellular components, patterned activity and plasticity of co-active neurons in local networks

表征即使不是神经科学的主旋律，也是神经科学的一项基本原则：我们都相信，感知、记忆、思想、选择、行动和感觉在神经系统中都有物理联系。越来越多的证据表明，神经元表征是由可复制的多神经元活动模式形成的。因此，基本的认知或行为状态与一组共同活动的神经元有因果关系，称为神经元集合。我们使用大量的现代方法来监控、分析和操纵定义的功能系统和网络中的神经元集合。我们的技术方法包括单细胞和多细胞水平的电生理学、神经元活动的生命成像、病毒介导的特定细胞群体的修饰、光遗传操作、解剖示踪技术、超微结构分析和高级数据分析。我们研究行为啮齿动物或脑片的助记、感觉、情绪和执行控制系统。用这种跨学科的方法和统一的函数系综思想，我们将澄清三个重要的问题：i)选定的神经元是如何被缠绕到一个系综中的，其他神经元是如何被排除的？Ii)不同网络中时空活动模式的特征是什么？iii)集合如何适应新的体验和变化的内部或外部条件？我们希望共同有助于理解细胞和网络水平的机制，允许我们的神经系统以功能适应的方式形成表征。

Representation is a fundamental principle of neuroscience, if not its overarching leitmotif: We all believe that perceptions, memories, thoughts, choices, actions and feelings have a physical correlate in the nervous system. Converging evidence indicates that neuronal representations are formed by reproducible multi-neuronal activity patterns. Thus, elementary cognitive or behavioral states are causally linked to groups of co-active neurons, called neuronal ensembles.We use a large variety of modern approaches to monitor, analyse and manipulate neuronal ensembles in defined functional systems and networks. Our technical approaches comprise electrophysiology at the single- and multiple cell level, life imaging of neuronal activity, virus-mediated modification of defined cell populations, optogenetic manipulations, anatomical tracing techniques, ultrastructural analyses and advanced data analysis. We study mnemonic, sensory, emotional and executive control systems in behaving rodents or brain slice preparations. With this interdisciplinary approach and the unifying idea of functional ensembles as elementary representations we will clarify three important questions: i) How are selected neurons entrained into an ensemble, and how are others excluded? ii) What are the characteristic features of spatio-temporal activity patterns in different networks?iii) How do ensembles adapt to novel experience and to changing inner or outer conditions?Together, we hope to contribute to understanding the cell- and network-level mechanisms allowing our nervous system to form representations in a functionally adaptive manner.