Resting-state EEG functional networks organization and individual differences in the task-unrelated thoughts: Greater Mind-Wanderers exhibit weaker default mode network integration

When performing cognitively demanding tasks, we all sometimes experience a momentary distractions or our stream of consciousness is intercepted by personal associations. This phenomenon is called Mind Wandering (MW) and it became a subject of neuroscientific investigations. Off-task thoughts can be analyzed during task performance, but currently MW is also understood as a dimension of individual differences in cognitive processing. We wanted to recognize the intrinsically-organized functional networks which could be considered as the neuronal basis for the MW dispositional variability. To achieve this goal we have recruited a group of normal adults, the group was eventually divided in half on the basis of participants scores on the scale measuring dispositional MW. Next, these groups were compared regarding arrangement of preselected intrinsic functional networks which were reconstructed on the basis of multi-channel signal-source resting-state EEG. It appeared that subjects who tend to mind wander often exhibited decreased synchronization within the default mode network, and simultaneously strengthened connectivity between ‘on-task’ networks of diverse functional specificity. Such within- and between networks integrity patterns might suggest that greater Mind Wanderers have atypical organization of resting-state brain activity which may translate into attenuated resources needed to maintain attentional control in task-related conditions.