Gordon Evan M, Breeden Andrew L, Bean Stephanie E, Vaidya Chandan J
Interdisciplinary Program in Neuroscience, Georgetown University Medical Center, Washington, DC.
Hum Brain Mapp. 2014 Mar;35(3):1004-17. doi: 10.1002/hbm.22230. Epub 2012 Dec 26.
We examined whether altered connectivity in functional networks during working memory performance persists following conclusion of that performance, into a subsequent resting state. We conducted functional magnetic resonance imaging (fMRI) in 50 young adults during an initial resting state, followed by an N-back working memory task and a subsequent resting state, in order to examine changes in functional connectivity within and between the default-mode network (DMN) and the task-positive network (TPN) across the three states. We found that alterations in connectivity observed during the N-back task persisted into the subsequent resting state within the TPN and between the DMN and TPN, but not within the DMN. Further, both speed of working memory performance and TPN connectivity strength during the N-back task predicted connectivity strength in the subsequent resting state. Finally, DMN connectivity measured before and during the N-back task predicted individual differences in self-reported inattentiveness, but this association was not found during the post-task resting state. Together, these findings have important implications for models of how the brain recovers following effortful cognition, as well as for experimental designs using resting and task scans.
我们研究了在工作记忆表现过程中功能网络连接性的改变，在该表现结束后，是否会持续到随后的静息状态。我们对50名年轻人进行了功能磁共振成像（fMRI），先进行初始静息状态，接着是N-back工作记忆任务，然后是后续静息状态，以检查在这三种状态下默认模式网络（DMN）和任务积极网络（TPN）内部以及它们之间功能连接性的变化。我们发现，在N-back任务期间观察到的连接性改变在TPN内部以及DMN和TPN之间持续到了随后的静息状态，但在DMN内部没有。此外，N-back任务期间工作记忆表现的速度和TPN连接强度都预测了随后静息状态下的连接强度。最后，在N-back任务之前和期间测量的DMN连接性预测了自我报告的注意力不集中的个体差异，但在任务后静息状态期间未发现这种关联。总之，这些发现对于大脑在费力认知后如何恢复的模型以及使用静息和任务扫描的实验设计具有重要意义。
