Wienke Christian, Bartsch Mandy V, Vogelgesang Lena, Reichert Christoph, Hinrichs Hermann, Heinze Hans-Jochen, Dürschmid Stefan
Department of Neurology, Otto-von-Guericke University, Leipziger Str. 44, 39120 Magdeburg, Germany.
Department of Behavioral Neurology, Leibniz Institute for Neurobiology, Brenneckestr. 6, 39118 Magdeburg, Germany.
Cereb Cortex Commun. 2021 Jan 15;2(1):tgab001. doi: 10.1093/texcom/tgab001. eCollection 2021.
Mind-wandering (MW) is a subjective, cognitive phenomenon, in which thoughts move away from the task toward an internal train of thoughts, possibly during phases of neuronal sleep-like activity (local sleep, LS). MW decreases cortical processing of external stimuli and is assumed to decouple attention from the external world. Here, we directly tested how indicators of LS, cortical processing, and attentional selection change in a pop-out visual search task during phases of MW. Participants' brain activity was recorded using magnetoencephalography, MW was assessed via self-report using randomly interspersed probes. As expected, the performance decreased under MW. Consistent with the occurrence of LS, MW was accompanied by a decrease in high-frequency activity (HFA, 80-150 Hz) and an increase in slow wave activity (SWA, 1-6 Hz). In contrast, visual attentional selection as indexed by the N2pc component was enhanced during MW with the N2pc amplitude being directly linked to participants' performance. This observation clearly contradicts accounts of attentional decoupling that would predict a decrease in attention-related responses to external stimuli during MW. Together, our results suggest that MW occurs during phases of LS with processes of attentional target selection being upregulated, potentially to compensate for the mental distraction during MW.
思绪游走（MW）是一种主观的认知现象，在此过程中，思绪可能在类似神经元睡眠的活动（局部睡眠，LS）阶段从任务转移至一连串内在思绪。MW会减少对外部刺激的皮质处理，并被认为会使注意力与外部世界脱钩。在此，我们直接测试了在MW阶段，弹出式视觉搜索任务中LS、皮质处理和注意力选择的指标是如何变化的。使用脑磁图记录参与者的大脑活动，通过随机穿插的探针进行自我报告来评估MW。正如预期的那样，在MW状态下表现会下降。与LS的出现一致，MW伴随着高频活动（HFA，80 - 150赫兹）的减少和慢波活动（SWA，1 - 6赫兹）的增加。相比之下，由N2pc成分所索引的视觉注意力选择在MW期间增强，且N2pc振幅与参与者的表现直接相关。这一观察结果明显与注意力脱钩的观点相矛盾，后者预测在MW期间对外部刺激的注意力相关反应会减少。总之，我们的结果表明，MW发生在LS阶段，同时注意力目标选择过程被上调，这可能是为了补偿MW期间的精神分心。
