Role of the Default Mode Network in Cognitive Transitions
Cerebral Cortex June 21, 2018 Verity Smith, Daniel J Mitchell, John Duncan 173 citations
The default mode network (DMN) is typically thought to support internally focused thought, but a new brain imaging study shows it also activates during certain external task switches. Using fMRI, 24 participants performed a task-switching experiment. The DMN increased activity not only during task switches, replicating prior findings, but also during brief rests and task restarts after rest. These results challenge theories that restrict DMN function to internal or self-directed cognition. The authors propose that the DMN encodes scene, episode, or context by integrating spatial, self-referential, and temporal information. Context representations are strong at rest, but re-reference to context also occurs at major cognitive transitions.