The 'Task' of Mind-Wandering Splits Both Multiple Demand and Default Mode Regions and Ramps-up the Deactivating Regions

Area of Science:

• Cognitive Neuroscience
• Neuroimaging
• Brain Function

Background:

• Multiple demand (MD) brain regions are activated by tasks requiring cognitive control, such as attention and working memory.
• Demanding tasks often involve deliberative cognition, where mental processes are not automatic.
• The role of deliberativeness itself in activating MD regions, independent of task demands, remains unclear.

Purpose of the Study:

• To investigate if the deliberativeness of cognition activates MD regions irrespective of task-related demands.
• To explore the neural correlates of intentionally wandering the mind during cognitive tasks.

Main Methods:

• Participants were instructed to deliberately and intensely wander their minds during specific task periods.
• Functional magnetic resonance imaging (fMRI) was used to monitor brain activity.
• Activity patterns were analyzed in relation to task periods and rest periods.

Main Results:

• A subset of MD regions, including the pre-supplementary motor area (preSMA), anterior insula, and posterior middle frontal gyrus, showed activation during deliberate mind-wandering.
• Other regions, such as the intraparietal sulcus and right anterior prefrontal cortex, deactivated.
• Specific MD regions (e.g., preSMA) exhibited greater activation during deliberate mind-wandering than during demanding working memory tasks.
• Dissociations were observed in the Default Mode Network (DMN), with some areas deactivating and others activating.
• Deactivating regions showed increased activity over the duration of the 'task,' even in the absence of sequential organizing demands.

Conclusions:

• Cognitive deliberativeness, independent of task demands, can engage specific multiple demand (MD) brain regions.
• The findings reveal a dissociation within MD networks and the Default Mode Network (DMN) during intentional mind-wandering.
• The observed ramp-up in activity within deactivating regions suggests this pattern occurs in any defined task, not solely those with sequential demands.