Psychology Department, Indiana Wesleyan University, Marion, IN, 46953, USA; Lumen Research Institute, Excelsia College, Sydney, Australia.
Department of Neurobiology and Anatomy, McGovern Medical School, University of Texas Health Science Center, Houston, TX, 77030, USA.
Neurosci Biobehav Rev. 2019 May;100:77-84. doi: 10.1016/j.neubiorev.2019.02.010. Epub 2019 Feb 18.
According to traditional systems consolidation theories neocortical long-term plasticity (i.e., cellular consolidation) lags behind, and is dependent upon, hippocampal long-term plasticity. In this review, we examine accumulating evidence that local neocortical and hippocampal cellular consolidation occurs with a similar time-course. The implication is that the rate-limiting step for systems consolidation is the time it takes for cellular consolidation in longer connections throughout a more distributed extra-hippocampal system that comes to coordinate distributed neocortical activity during recall. The hippocampus is, thus, crucial for the development of this extra-hippocampal coordinating system, and acts to coordinate activities crucial for recall until it develops. Recent work on schema formation, engram cells, and the role of sleep in consolidation add substantial evidence for this "unified theory" of systems and cellular consolidation. Here, we discuss this evidence, its implications, and consider remaining questions.
根据传统的系统巩固理论,新皮层的长期可塑性(即细胞巩固)滞后于并依赖于海马体的长期可塑性。在这篇综述中,我们考察了越来越多的证据表明,局部新皮层和海马体的细胞巩固具有相似的时间过程。这意味着,系统巩固的限速步骤是在更长的连接中进行细胞巩固所需的时间,这些连接分布在更广泛的海马体外系统中,在回忆期间协调分布式新皮层活动。因此,海马体对于发展这种海马外协调系统至关重要,并在其发展之前协调回忆所需的活动。最近关于图式形成、记忆痕迹细胞和睡眠在巩固中的作用的研究为这一“系统和细胞巩固的统一理论”提供了大量证据。在这里,我们讨论这些证据、其含义以及考虑剩余的问题。