Department of Psychology, New York University, 6 Washington Place, New York, NY 10003, USA.
Neuropsychologia. 2011 May;49(6):1428-34. doi: 10.1016/j.neuropsychologia.2010.12.020. Epub 2010 Dec 21.
The prefrontal cortex (PFC) and posterior parietal cortex (PPC) are critical neural substrates for working memory. Neural activity persists in these regions during the maintenance of a working memory representation. Persistent activity, therefore, may be the neural mechanism by which information is temporarily maintained. However, the nature of the representation or what is actually being represented by this persistent activity is not well understood. In this review, we summarize the recent functional magnetic resonance imaging (fMRI) studies conducted in our laboratory that test hypotheses about the nature of persistent activity during a variety of spatial cognition tasks. We find that the same areas in the PFC and PPC that show persistent activity during the maintenance of a working memory representation also show persistent activity during the maintenance of spatial attention and the maintenance of motor intention. Therefore, we conclude that persistent activity is not specific to working memory, but instead, carries information that can be used generally to support a variety of cognitions. Specifically, activity in topographically organized maps of prioritized space in PFC and PPC could be read out to guide attention allocation, spatial memory, and motor planning.
前额叶皮层（PFC）和顶后皮质（PPC）是工作记忆的关键神经基质。在工作记忆表征的维持过程中，这些区域的神经活动持续存在。因此，持续的活动可能是信息暂时维持的神经机制。然而，这种持续活动所代表的表征的本质或实际上代表的内容还不是很清楚。在这篇综述中，我们总结了我们实验室最近进行的功能磁共振成像（fMRI）研究，这些研究检验了关于在各种空间认知任务中持续活动的本质的假设。我们发现，在工作记忆表征的维持过程中表现出持续活动的 PFC 和 PPC 中的相同区域，在空间注意力的维持和运动意图的维持过程中也表现出持续活动。因此，我们得出结论，持续的活动并不是专门针对工作记忆的，而是携带可以用来支持各种认知的信息。具体来说，PFC 和 PPC 中优先空间的地形组织图中的活动可以被读取出来，以指导注意力分配、空间记忆和运动计划。
