Externally-Focused Task Switch Activity in the 'Internally-Directed' Default Mode Network
Study at a glance
AI-extracted from the abstract| Characteristics | Observational cohort |
|---|---|
| Sample size | 24 |
| Population | Healthy adults performing a task switch experiment |
| Topics | Default mode network |
| Key findings | The DMN showed activation increases during externally-focused task switches, brief rests, and task restarts after rest, in addition to replicating previous task switch effects. The authors propose that the DMN encodes scene, episode, or context by integrating spatial, self-referential, and temporal information. |
Abstract
A frequently repeated finding is that the default mode network (DMN) shows activation decreases during externally-focused tasks. This finding has led to an emphasis in DMN research on internally-focused self-relevant thought processes. A recent study, in contrast, implicates the DMN in substantial externally-focused task switches. Using functional magnetic resonance imaging, we scanned 24 participants performing a task switch experiment. Whilst replicating previous DMN task switch effects, we also found large DMN increases for brief rests as well as task restarts after rest. Our findings are difficult to explain using theories strictly linked to internal or self-directed cognition. In line with principal results from the literature, we suggest 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.