Department of Cognitive Neuroscience, Faculty of Psychology and Neuroscience, Maastricht University, Maastricht, The Netherlands.
Maastricht Brain Imaging Center (M-BIC), Maastricht, The Netherlands.
Brain Behav. 2018 Aug;8(8):e01034. doi: 10.1002/brb3.1034. Epub 2018 Jun 22.
Linking individual task performance to preceding, regional brain activation is an ongoing goal of neuroscientific research. Recently, it could be shown that the activation and connectivity within large-scale brain networks prior to task onset influence performance levels. More specifically, prestimulus default mode network (DMN) effects have been linked to performance levels in sensory near-threshold tasks, as well as cognitive tasks. However, it still remains uncertain how the DMN state preceding cognitive tasks affects performance levels when the period between task trials is long and flexible, allowing participants to engage in different cognitive states.
We here investigated whether the prestimulus activation and within-network connectivity of the DMN are predictive of the correctness and speed of task performance levels on a cognitive (match-to-sample) mental rotation task, employing a sparse event-related functional magnetic resonance imaging (fMRI) design.
We found that prestimulus activation in the DMN predicted the speed of correct trials, with a lower amplitude preceding correct fast response trials compared to correct slow response trials. Moreover, we found higher connectivity within the DMN before incorrect trials compared to correct trials.
These results indicate that pre-existing activation and connectivity states within the DMN influence task performance on cognitive tasks, both effecting the correctness and speed of task execution. The findings support existing theories and empirical work on relating mind-wandering and cognitive task performance to the DMN and expand these by establishing a relationship between the prestimulus DMN state and the speed of cognitive task performance.
将个体任务表现与之前的区域大脑激活联系起来是神经科学研究的一个持续目标。最近，人们可以证明任务开始前的大脑大网络中的激活和连接会影响表现水平。更具体地说，刺激前默认模式网络 (DMN) 的效应已经与感觉接近阈限任务以及认知任务的表现水平相关联。然而，当任务试验之间的时间间隔长且灵活，允许参与者参与不同的认知状态时，DMN 状态如何影响认知任务之前的表现水平仍然不确定。
我们在这里研究了在认知（匹配样本）心理旋转任务中，DMN 的刺激前激活和网络内连接是否可以预测任务表现水平的正确性和速度，采用稀疏事件相关功能磁共振成像 (fMRI) 设计。
我们发现 DMN 的刺激前激活预测了正确试次的速度，与正确慢反应试次相比，正确快反应试次的振幅较低。此外，我们发现错误试次前 DMN 内的连接性高于正确试次。
这些结果表明，DMN 内预先存在的激活和连接状态会影响认知任务的表现，同时影响任务执行的正确性和速度。这些发现支持了将漫游思维和认知任务表现与 DMN 联系起来的现有理论和实证工作，并通过建立刺激前 DMN 状态与认知任务表现速度之间的关系来扩展这些工作。
