Department of Clinical, Neuro and Developmental Psychology, Faculty of Behavioral and Movement Sciences, Institute for Brain and Behavior Amsterdam, Vrije Universiteit Amsterdam, 1081 BT Amsterdam, The Netherlands.
Donders Institute for Brain, Cognition and Behaviour, Radboud University Nijmegen Medical Centre, 6500 HB, Nijmegen, The Netherlands.
Learn Mem. 2018 Dec 17;26(1):9-19. doi: 10.1101/lm.048199.118. Print 2019 Jan.
Intrinsic network interactions may underlie individual differences in the ability to remember. The default mode network (DMN) comprises subnetworks implicated in memory, and interactions between the DMN and frontoparietal network (FPN) were shown to support mnemonic processing. However, it is unclear if such interactions during resting-state predict episodic memory ability. We investigated whether intrinsic network interactions within and between the DMN and FPN are related to individual differences in memory performance. Resting-state activity was measured using functional MRI in healthy young adults followed by a memory test for object-location associations that were studied 3 d earlier. We identified two subnetworks within the DMN, the main-DMN and the medial temporal lobe, retrosplenial cortex (MTL_RSC)-DMN. Further, we found regions forming the FPN. Memory performance was associated with lower connectivity within the MTL_RSC-DMN, and stronger connectivity between the main-DMN and FPN. Exploratory whole-brain analysis revealed stronger MTL connectivity with the left posterior parietal cortex that was related to better memory performance. Furthermore, we found increased task-evoked activation during successful retrieval within the main-DMN and FPN, but not within the MTL_RSC-DMN. In sum, lower intrinsic connectivity within the MTL_RSC-DMN, combined with stronger connectivity between the main-DMN and FPN, explain individual differences in memory ability.
内在网络相互作用可能是个体记忆能力差异的基础。默认模式网络 (DMN) 由与记忆相关的子网组成，并且 DMN 与额顶网络 (FPN) 之间的相互作用被证明支持记忆处理。然而，尚不清楚静息状态下的这种相互作用是否可以预测情节记忆能力。我们研究了 DMN 内部和 DMN 与 FPN 之间的内在网络相互作用是否与记忆表现的个体差异有关。使用功能磁共振成像 (fMRI) 在健康的年轻成年人中测量静息状态活动，然后进行物体位置关联的记忆测试，这些测试是在 3 天前进行的。我们确定了 DMN 中的两个子网，即主要 DMN 和内侧颞叶、后扣带回皮层 (MTL_RSC)-DMN。此外，我们还发现了形成 FPN 的区域。记忆表现与 MTL_RSC-DMN 内的连接性降低以及主要 DMN 和 FPN 之间的连接性增强有关。探索性全脑分析显示，与记忆表现较好相关的是左侧后顶叶皮层与 MTL 的连接性增强。此外，我们发现主要 DMN 和 FPN 内的任务诱发激活在成功检索时增加，但 MTL_RSC-DMN 内没有增加。总之，MTL_RSC-DMN 内的内在连接性降低，与 FPN 之间的连接性增强，解释了记忆能力的个体差异。
