The default mode network (DMN) is a set of brain regions active during rest and self-referential thought. This review of studies up to August 2016 examined how DMN functional connectivity varies in healthy people by age, sex, cognitive function, and analysis method. DMN connectivity follows an inverse U-shape across the lifespan: strongest in adulthood, lowest in children and the elderly. Cognitive function positively correlates with DMN connectivity. Females show stronger intranetwork connectivity than males. Effects of analysis type were inconclusive. A voxel-wise meta-analysis for age confirmed an immature network in children versus adults and a stronger network in adults versus the elderly. Defining normal variation may help identify DMN changes in pathology.
Mindfulness-based cognitive therapy (MBCT) fosters metacognitive skills—specifically the ability to decenter from thoughts and feelings and to approach them with curiosity—that are not acquired through antidepressant medication alone. In a randomized trial, patients who discontinued antidepressants and received MBCT showed significant increases in decentering and wider experiences, while those who continued medication or switched to placebo did not. These skills predicted lower depression scores at 6-month follow-up. The findings suggest that MBCT's effectiveness for preventing depressive relapse may stem from cultivating a decentered, curious stance toward one's own mental events.