Probing the neural signature of mind wandering with simultaneous fMRI-EEG and pupillometry

Abstract

Mind wandering reflects the shift in attentional focus from task-related cognition driven by external stimuli toward self-generated and internally-oriented thought processes. Although such task-unrelated thoughts (TUTs) are pervasive and detrimental to task performance, their underlying neural mechanisms are only modestly understood. To investigate TUTs with high spatial and temporal precision, we simultaneously measured fMRI, EEG, and pupillometry in healthy adults while they performed a sustained attention task with experience sampling probes. Features of interest were extracted from each modality at the single-trial level and fed to a support vector machine that was trained on the probe responses. Compared to task-focused attention, the neural signature of TUTs was characterized by weaker activity in the default mode network but elevated activity in its anticorrelated network, stronger functional coupling between these networks, widespread increase in alpha, theta, delta, but not beta, frequency power, predominantly reduced amplitudes of late, but not early, event-related potentials, and larger baseline pupil size. Particularly, information contained in dynamic interactions between large-scale cortical networks was predictive of transient changes in attentional focus above other modalities. Together, our results provide insight into the spatiotemporal dynamics of TUTs and the neural markers that may facilitate their detection.

The neural mechanisms behind mind wandering phenomenon: A brief review

“…The study of mind wandering in cognitive neuroscience aims to explore its neural basis, brain mechanisms, and its relationship with cognitive processes such as cognitive control and attention allocation. This is a major step forward in our understanding of the composition and operations of human mental processes [5][6][7][8][9]. ISSN 2706-6827 Vol.…”

Spontaneous activity changes in large-scale cortical networks in older adults couple to distinct hemodynamic morphology

“…One possible explanation for this distinction could be that the aDMN state corresponds to selfreferential thought. Establishing and buffering internal trains of thought from disruptions by the external world may involve intricate cognitive-control neural dynamics, including inhibitory influences both among the inferior frontal gyrus and DMN medial nodes as well as from the frontoparietal control network 191,192 . Consistent with such complex dynamics, the aDMN state evoked initial BOLD reductions involving the medial and inferolateral prefrontal cortices, followed by a positive BOLD response encompassing the dorsolateral prefrontal and medial parietal cortices.…”