Dynamic functional connectivity of the default mode network tracks daydreaming

Area of Science:

• Neuroscience
• Cognitive Science

Background:

• Humans frequently experience stimulus-independent thoughts, commonly called daydreaming or mind-wandering.
• Understanding how spontaneous brain activity represents conscious daydreaming versus unconscious intrinsic processes is crucial.

Purpose of the Study:

• To investigate the hypothesis that the dynamics of brain network functional connectivity (FC) are associated with daydreaming.
• To differentiate between static and dynamic FC in relation to daydreaming tendencies and real-time mind-wandering.

Main Methods:

• Assessed daydreaming frequency using the daydreaming frequency scale (DDF).
• Utilized resting-state fMRI (rs-fMRI) and task-based fMRI with thought probes.
• Analyzed static FC and dynamic FC (FC variability, FCV) within the default mode network (DMN).

Main Results:

• Individual differences in DDF negatively correlated with static FC between the posterior cingulate cortex and a ventral DMN subsystem.
• DDF positively correlated with dynamic FC variability (FCV) in the DMN during rest.
• Dynamic FC, but not static FC, within the DMN positively correlated with self-reported mind-wandering during stimulation.

Conclusions:

• Temporal dynamics of spontaneous brain activity, particularly within the DMN, are linked to conscious daydreaming.
• Dynamic FC measures offer insights into the fluctuating nature of mind-wandering.
• These findings help distinguish conscious cognitive processes from unconscious brain activity.