Human Brain Mapping
January 24, 2008
Lucina Q. Uddin, A.M. Clare Kelly, Bharat B. Biswal et al.
1,198 citations
The default mode network (DMN), which is most active when the mind is at rest, is often treated as a single system, but its two main hubs—the ventromedial prefrontal cortex (vmPFC) and the posterior cingulate cortex (PCC)—interact with different task-focused brain networks. Using resting-state fMRI and a seed correlation approach, activity in vmPFC negatively predicted activity in networks for visual spatial and temporal attention, while activity in PCC negatively predicted activity in motor control circuits. Granger causality analyses indicated that vmPFC and PCC exert greater influence on their anticorrelated networks than the reverse, suggesting these DMN nodes may directly modulate task-positive networks. The DMN is thus more heterogeneous than commonly appreciated.
NeuroImage
April 11, 2010
Kaustubh Supekar, Lucina Q. Uddin, Katherine E. Prater et al.
548 citations
The default-mode network (DMN) undergoes significant developmental changes in functional and structural connectivity from childhood to adulthood, but these changes are not uniform across all DMN nodes. The connection between the posterior cingulate cortex (PCC) and medial prefrontal cortex (mPFC) along the cingulum bundle is the most immature link in children. Structural connectivity between PCC and left medial temporal lobe is weak or non-existent in children, yet functional connectivity does not differ from adults. Gray matter volume differences and macrostructural and microstructural differences in the dorsal cingulum bundle also appear. Maturation of PCC-mPFC structural connectivity likely supports self-related and social-cognitive functions emerging during adolescence.
Frontiers in Human Neuroscience
January 1, 2013
Istvan Molnar-Szakacs, Lucina Q. Uddin
221 citations
The default mode network (DMN) is not a single, uniform system but contains functionally distinct subdivisions with unique connectivity patterns. Recent advances in resting-state functional connectivity reveal complex organization within key DMN nodes—medial prefrontal cortex and posterior cingulate cortex—and between these nodes and other brain systems. This review examines how DMN subdivisions relate to self-referential and social-cognitive processing. The authors propose that embodied simulation and mentalizing work together to provide coherent representations of self and others: embodiment engages the same neural systems for self- and other-understanding through simulation, while mentalizing uses high-level conceptual information to infer mental states. DMN nodes selectively interact with brain systems for embodiment and mentalizing, including the mirror neuron system, to support social-cognitive demands.