Center for Neural Science, New York University, 4 Washington Place, New York, NY 20003, USA.
Trends Neurosci. 2021 Nov;44(11):888-902. doi: 10.1016/j.tins.2021.09.001. Epub 2021 Oct 12.
Half a century ago persistent spiking activity in the neocortex was discovered to be a neural substrate of working memory. Since then scientists have sought to understand this core cognitive function across biological and computational levels. Studies are reviewed here that cumulatively lend support to a synaptic theory of recurrent circuits for mnemonic persistent activity that depends on various cellular and network substrates and is mathematically described by a multiple-attractor network model. Crucially, a mnemonic attractor state of the brain is consistent with temporal variations and heterogeneity across neurons in a subspace of population activity. Persistent activity should be broadly understood as a contrast to decaying transients. Mechanisms in the absence of neural firing ('activity-silent state') are suitable for passive short-term memory but not for working memory - which is characterized by executive control for filtering out distractors, limited capacity, and internal manipulation of information.
半个世纪前，人们发现新皮层中的持续尖峰活动是工作记忆的神经基础。从那时起，科学家们一直在努力从生物和计算两个层面来理解这一核心认知功能。本文回顾了一些研究，这些研究逐渐支持了一个关于记忆持久活动的递归回路的突触理论，该理论依赖于各种细胞和网络基质，并通过一个多吸引子网络模型进行数学描述。至关重要的是，大脑的记忆吸引子状态与神经元在种群活动子空间中的时间变化和异质性一致。持久活动应该被广泛理解为与衰减瞬变的对比。在没有神经放电的情况下的机制（“活动静默状态”）适合被动的短期记忆，但不适合工作记忆——工作记忆的特点是过滤干扰物的执行控制、有限的容量和信息的内部操作。
