Department of Neurobiology and Behavior, State University of New York at Stony Brook, Stony Brook, NY 11794, United States; Graduate Program in Neuroscience, State University of New York at Stony Brook, Stony Brook, NY 11794, United States.
Department of Neurobiology and Behavior, State University of New York at Stony Brook, Stony Brook, NY 11794, United States; Graduate Program in Neuroscience, State University of New York at Stony Brook, Stony Brook, NY 11794, United States.
Curr Opin Neurobiol. 2019 Oct;58:37-45. doi: 10.1016/j.conb.2019.06.007. Epub 2019 Jul 18.
Metastable brain dynamics are characterized by abrupt, jump-like modulations so that the neural activity in single trials appears to unfold as a sequence of discrete, quasi-stationary 'states'. Evidence that cortical neural activity unfolds as a sequence of metastable states is accumulating at fast pace. Metastable activity occurs both in response to an external stimulus and during ongoing, self-generated activity. These spontaneous metastable states are increasingly found to subserve internal representations that are not locked to external triggers, including states of deliberations, attention and expectation. Moreover, decoding stimuli or decisions via metastable states can be carried out trial-by-trial. Focusing on metastability will allow us to shift our perspective on neural coding from traditional concepts based on trial-averaging to models based on dynamic ensemble representations. Recent theoretical work has started to characterize the mechanistic origin and potential roles of metastable representations. In this article we review recent findings on metastable activity, how it may arise in biologically realistic models, and its potential role for representing internal states as well as relevant task variables.
亚稳态大脑动力学的特征是突然的、跳跃式的调制，使得单个试验中的神经活动似乎展开为一系列离散的、准静态的“状态”。越来越多的证据表明，皮质神经活动是作为一系列亚稳态状态展开的。亚稳态活动既发生在对外界刺激的反应中，也发生在持续的、自发产生的活动中。这些自发的亚稳态状态越来越多地被发现用于内部表示，而内部表示不受外部触发的限制，包括审议、注意和期望状态。此外，通过亚稳态状态对刺激或决策进行解码可以逐次进行。关注亚稳态将使我们能够将神经编码的视角从基于试验平均的传统概念转变为基于动态整体表示的模型。最近的理论工作已经开始描述亚稳态表示的机械起源和潜在作用。在本文中，我们回顾了最近关于亚稳态活动的发现，它如何在生物现实模型中产生，以及它在表示内部状态和相关任务变量方面的潜在作用。
