Department of Rehabilitation Psychology, Daegu University, Gyeongsan-si, Republic of Korea.
Hum Brain Mapp. 2019 Dec 1;40(17):4912-4933. doi: 10.1002/hbm.24747. Epub 2019 Aug 2.
It remains unclear whether and to what extent working memory (WM) temporal subprocesses (i.e., encoding, maintenance, and retrieval) involve shared or distinct intrinsic networks. To address this issue, I constructed a model of intrinsic network contributions to different WM phases and then evaluated the validity of the model by performing a quantitative meta-analysis of relevant functional neuroimaging data. The model suggests that the transition from the encoding to maintenance and to retrieval stages involves progressively decreasing involvement of the dorsal attention network (DAN), but progressively increasing involvement of the frontoparietal control network (FPCN). Separate meta-analysis of each phase effect and direct comparisons between them yielded results that were largely consistent with the model. This evidence included between-phase double dissociations that were consistent with the model, such as encoding > maintenance contrast showing some DAN, but no FPCN, regions, and maintenance > encoding contrast showing the reverse, that is, some FPCN, but no DAN, regions. Two closely juxtaposed regions that are members of the DAN and FPCN, such as inferior frontal junction versus caudal prefrontal cortex and superior versus inferior intraparietal sulcus, showed a high degree of functional differentiation. Although all regions identified in the present study were already identified in previous WM studies, this study uniquely enhances our understating of their roles by clarifying their network membership and specific associations with different WM phases.
目前尚不清楚工作记忆(WM)的时间子过程(即编码、维持和提取)是否以及在何种程度上涉及共享或独特的内在网络。为了解决这个问题,我构建了一个内在网络对不同 WM 阶段贡献的模型,然后通过对相关功能神经影像学数据进行定量元分析来评估该模型的有效性。该模型表明,从编码到维持再到提取阶段的转变涉及到背侧注意网络(DAN)的参与程度逐渐降低,而额顶控制网络(FPCN)的参与程度逐渐增加。对每个阶段效应的单独元分析以及它们之间的直接比较得出的结果与该模型基本一致。这方面的证据包括与模型一致的阶段间双重分离,例如编码>维持对比显示出一些 DAN,但没有 FPCN 区域,而维持>编码对比则显示出相反的情况,即一些 FPCN,但没有 DAN 区域。DAN 和 FPCN 的两个紧密相邻的区域,如额下回与额前皮质和顶内沟的上部分与下部分,表现出高度的功能分化。虽然本研究中确定的所有区域在以前的 WM 研究中已经被确定,但通过阐明它们的网络成员身份以及与不同 WM 阶段的特定关联,本研究独特地增强了我们对它们作用的理解。