Nature reviews. Neuroscience
July 5, 2021
Jonathan Smallwood, Boris C. Bernhardt, Robert Leech et al.
970 citations
The default mode network (DMN) is a set of brain regions in the parietal, temporal, and frontal cortex that typically reduce activity during attention-demanding tasks but increase activity during complex cognition linked to memory or abstract thought. These regions are located farthest from sensory and motor systems. The paper considers how knowledge of the DMN's topographic characteristics can be used to better understand its contributions to cognition and behavior.
Proceedings of the National Academy of Sciences
August 27, 2018
Mladen Sormaz, Charlotte Murphy, Hao-ting Wang et al.
291 citations
The default mode network (DMN), a set of brain regions traditionally linked to off-task or mind-wandering states, actually contributes to detailed, task-relevant cognition during active tasks. Using fMRI, participants performed working-memory tasks while reporting their thoughts. Patterns of neural activity showed that distinctions between on- and off-task thought involved regions near sensory and motor cortex, not the DMN. However, the level of detail in ongoing thought corresponded to activity patterns within the DMN during memory maintenance. These findings indicate the DMN supports detailed cognition under active task conditions, challenging the view that it is solely task-negative.
Neuroimage
January 12, 2018
Charlotte Murphy, Elizabeth Jefferies, Shirley-Ann Rueschemeyer et al.
288 citations
The default mode network supports cognition independent of immediate environment and higher-order conceptual representations. A novel paradigm manipulated perceptual information availability and representational complexity during decision-making. Brain regions including left and right angular gyri and left middle temporal gyrus responded when cognition combined stimulus independence with multi-modal information. These default mode network sites showed stronger response to demanding memory judgments than easier perceptual tasks, contradicting the view they support automatic cognition. These regions were at the extreme end of a macroscale gradient from sensorimotor to transmodal cortex, suggesting functional distance from sensory input enables conceptually rich cognitive states in absence of input.
PLoS One
May 13, 2014
Krzysztof J. Gorgolewski, Daniel J. Lurie, Sebastian Urchs et al.
180 citations
Self-generated thoughts—such as daydreaming or mind-wandering—are linked to distinct patterns of spontaneous brain activity. Using the New York Cognition Questionnaire (NYC-Q) and resting-state fMRI data from the Nathan Kline Rockland Enhanced sample, researchers found that thoughts cluster into dimensions of content (future-related, past-related, positive, negative, social) and form (words, images, specificity). Individuals who reported more imagery showed greater low-frequency fluctuations in perigenual cingulate cortex, part of the default-mode network. Those with more future-oriented thoughts showed less homogeneous neural fluctuations in lateral occipital cortex, suggesting decoupling from sensory processing. Self-generated thought is a heterogeneous category, and studying its content helps understand brain dynamics.
Schizophrenia Bulletin
June 8, 2016
Ben Alderson-Day, Kelly Diederen, Charles Fernyhough et al.
134 citations
Resting-state brain networks may help explain hallucinations across different sensory modalities and populations. This report from the International Consortium on Hallucination Research reviews evidence linking resting-state alterations to auditory hallucinations, finding connectivity differences in left-hemisphere auditory and language regions, plus atypical interactions of the default mode network with networks for cognitive control and salience. Similar patterns appear in visual hallucinations, suggesting both domain-general and modality-specific network changes. However, high methodological heterogeneity across studies limits direct comparisons. The authors offer recommendations for future research on resting-state connectivity and hallucinations.
iScience
February 2, 2021
Jonathan Smallwood, Adam Turnbull, Hao-ting Wang et al.
130 citations
The landscape of ongoing thought is heterogeneous and shaped by both personal traits and environmental context. Recent work shows that attention and control systems organize experience in response to changing demands, while the default mode network contributes not only to task-negative or episodic content but also to the vividness of experience in both task contexts and spontaneous self-generated states. Multiple neural systems reflect the landscape of ongoing thought, and it is important to distinguish processes that shape how experience unfolds from those that regulate it.
Neuroimage
June 22, 2020
Brontë Mckeown, Will Strawson, Hao-ting Wang et al.
102 citations
People whose brain connectivity patterns make the sensorimotor system most distinct from the visual system are more likely to report thoughts about solving problems or goals and less likely to report thoughts about the past. This finding comes from a study where participants underwent resting-state fMRI and then completed a questionnaire about their thoughts during the scan. A non-linear dimension reduction algorithm identified components explaining the greatest variance in whole-brain connectivity patterns. The results suggest that unique patterns of experience are linked to distinct neurocognitive profiles, with unimodal systems playing an important role.
Scientific Reports
December 3, 2020
Theodoros Karapanagiotidis, Diego Vidaurre, Andrew J. Quinn et al.
82 citations
When people are not engaged in an explicit task, they experience a variety of self-generated thoughts, such as planning or reminiscing. Using machine learning to analyze brain activity from resting-state fMRI scans, researchers identified distinct neural states that recur over time. Two of these states predicted different patterns of thinking. One neural state, resembling activity seen during demanding tasks, was linked to problem-solving about the future. Another state, associated with less demanding conditions, was tied to intrusive thoughts about the past. These two states fell at opposite ends of a brain hierarchy related to cognitive demand. The findings show that tracking moment-to-moment changes in brain function can help classify self-generated mental states and that these states align with the brain's response to cognitive tasks.
Nature Neuroscience
January 28, 2025
Casey Paquola, Margaret Garber, Stefan Frässle et al.
58 citations
The default mode network (DMN) is a set of brain regions important for complex thought and behavior. By combining postmortem tissue analysis and brain scans, researchers found that the DMN contains different types of cells, some specialized for processing single senses, others for combining information, and still others for memory. The DMN includes regions that receive input from sensory areas and a core that is relatively cut off from direct sensory information. Analysis of how signals flow through the DMN showed it uniquely balances output across different levels of sensory processing. These findings provide a structural basis for understanding the DMN's broad role in brain function and cognition.
Scientific Reports
November 7, 2019
Meichao Zhang, Nicola Savill, Daniel S. Margulies et al.
48 citations
People often find their thoughts drifting away from the text they are reading, a tendency known as mind-wandering, which impairs comprehension and memory for the text. Using fMRI, the study found that individuals with poorer memory for texts show reduced activity in the left middle temporal gyrus in response to written input. This region sits at the intersection of the default mode, dorsal attention, and frontoparietal networks. In a resting-state analysis, stronger connectivity within the default mode network was associated with better text memory, while greater decoupling between the default mode network and medial visual regions was linked to more frequent mind-wandering. These results suggest that intrinsic brain network connectivity influences how attention stays engaged with reading.
May 29, 2019
Michael Lifshitz, Matthew D. Sacchet, Julia M. Huntenburg et al.
1 citation
Major depressive disorder involves abnormal communication between large-scale brain networks. A randomized, active-controlled trial tested whether mindfulness-based therapy could alter resting-state functional connectivity in clinically depressed patients. A brief, clinically effective mindfulness intervention functionally decoupled top-down control regions from brain areas involved in sensory, affective, and attentional processing. These findings identify specific neural targets of mindfulness training, offering new insight into how this therapeutic approach works.