Default-Mode Network Activity Identified by Group Independent Component Analysis
2
Citation
29
Reference
10
Related Paper
Citation Trend
Keywords:
Posterior cingulate
Balanced time perspective refers to the ability to flexibly switch between different temporal foci in an adaptive manner according to the current context. Functional connectivity within the default mode network (DMN) has been suggested to support balanced time perspective. The coupling between the DMN and fronto-parietal network (FPN) may drive many important expressions of internally directed cognition. However, it remains unclear whether balanced time perspective is supported by the interaction between the FPN and DMN. To examine these issues, we recruited 91 participants (52 males with mean age of 19.6, and 39 females with mean age of 20.0) to undergo resting-state brain imaging scan and to complete a questionnaire measuring balanced time perspective. Seed-based voxel-wise functional connectivity analyses implicated midline DMN regions including the anterior medial prefrontal cortex (amPFC) and posterior cingulate cortex (PCC) along with the anterior cingulate cortex (ACC), precuneus, and cerebellum in supporting a balanced time perspective. More importantly, functional connectivity between the right amPFC and right dorsal lateral prefrontal cortex (DLPFC) in the FPN was found to associate with balanced time perspective. Our findings suggest the importance of coordinated brain activity in supporting a balanced time perspective.
Posterior cingulate
Cite
Citations (3)
Most of the functional magnetic resonance imaging studies show that there are functional activities in the absence of any experimental tasks.These findings suggest the presence of default network during resting-state.Many experiments have also proved this default mode network(DMN)hypothesis is true.Certain brain regions,including posterior cingulate cortex,precuneus,medial and prefrontal cortex constitute the DMN.This article reviewed the advance in this field.
Posterior cingulate
Cite
Citations (0)
We used model based functional MRI independent component analysis approach for the detection and characterization of the described networks functioning during simple motor task execution. Direct connection between the task execution and anticorrelated functional connectivity of sensory-motor and default mode networks was shown. We observed blood oxygenation level dependent signal (BOLD) frequency characteristics of the default mode network (DMN) together with the sensory motor network (SMN). The results demonstrate a reproducible specific configuration of BOLD low-frequency spectrum. Neural network BOLD spectral pro㌳le approach may be used for future analysis of its functioning and dynamics rules of brain regions connectivity. Regions of precuneus and posterior cingulate cortex were shown to deactivate just partially. Sensorimotor and default-mode networks were functionally connected in the anticorrelated manner with the prevailing frequencies of the BOLD signal oscillation f1 = 0.0153 ± 0.0051 Hz and f2 = 0.0204 ± 0.0051 Hz, where f – frequency of BOLD oscillation. At our study we have found out, that only some separate parts of pC and PCC were deactivated during the task execution. This possibly might support the hypothesis that non deactivated regions of precuneus (pC) and posterior cingulate cortex (PCC) remain active to regulate the transitions from the activated state to the deactivated and back while monitoring the external environment and commands. The last may support the hypothesis of the role of posterior cingulate cortex as a “hub” in default mode networks where non deactivated parts remain active for further control of others default mode networks region state switching.
Posterior cingulate
Cite
Citations (0)
Posterior cingulate
Cite
Citations (2)
Abstract Activity and reactivity of the default mode network in the brain was studied using functional magnetic resonance imaging (fMRI) in 28 nondemented individuals with mild cognitive impairment (MCI), 18 patients with mild Alzheimer's disease (AD), and 41 healthy elderly controls (HC). The default mode network was interrogated by means of decreases in brain activity, termed deactivations, during a visual encoding task and during a nonspatial working memory task. Deactivation was found in the default mode network involving the anterior frontal, precuneus, and posterior cingulate cortex. MCI patients showed less deactivation than HC, but more than AD. The most pronounced differences between MCI, HC, and AD occurred in the very early phase of deactivation, reflecting the reactivity and adaptation of the network. The default mode network response in the anterior frontal cortex significantly distinguished MCI from both HC (in the medial frontal) and AD (in the anterior cingulate cortex). The response in the precuneus could only distinguish between patients and HC, not between MCI and AD. These findings may be consistent with the notion that MCI is a transitional state between healthy aging and dementia and with the proposed early changes in MCI in the posterior cingulate cortex and precuneus. These findings suggest that altered activity in the default mode network may act as an early marker for AD pathology. Hum Brain Mapp, 2005. © 2005 Wiley‐Liss, Inc.
Posterior cingulate
Cite
Citations (732)
Posterior cingulate
Task-positive network
Cite
Citations (1,163)
Functional neuroimaging studies provide converging evidence for existence of intrinsic brain networks activated during resting states and deactivated with selective cognitive demands. Whether task-related deactivation of the default mode network signifies depressed activity relative to the remaining brain or simply lower activity relative to its resting state remains controversial. We employed 3D arterial spin labeling imaging to examine regional cerebral blood flow (CBF) during rest, a spatial working memory task, and a second rest. Change in regional CBF from rest to task showed significant normalized and absolute CBF reductions in posterior cingulate, posterior-inferior precuneus, and medial frontal lobes . A Statistical Parametric Mapping connectivity analysis, with an a priori seed in the posterior cingulate cortex, produced deactivation connectivity patterns consistent with the classic "default mode network" and activation connectivity anatomically consistent with engagement in visuospatial tasks. The large task-related CBF decrease in posterior-inferior precuneus relative to its anterior and middle portions adds evidence for the precuneus' heterogeneity. The posterior cingulate and posterior-inferior precuneus were also regions of the highest CBF at rest and during task performance. The difference in regional CBF between intrinsic (resting) and evoked (task) activity levels may represent functional readiness or reserve vulnerable to diminution by conditions affecting perfusion.
Posterior cingulate
Statistical parametric mapping
Brain mapping
Cite
Citations (102)
The 'default mode network' is a set of brain regions showing correlated, low-frequency activity during rest. It includes the posterior cingulate/precuneus, medial prefrontal cortex, and bilateral inferior parietal cortex. Earlier studies have characterized this network using either region of interest-based correlation analyses or data-driven techniques; however, there is some disagreement over which method is superior. We conducted both types of analysis on a large (N=40) data set and also investigated age and sex differences in the network. Both region of interest-based analyses and independent component analysis identified the default mode network. Age and sex differences were small and there was less agreement between analytic techniques regarding age and sex effects than regarding default mode network structure.
Posterior cingulate
Task-positive network
Cite
Citations (227)
We have investigated functional connectivity of the default mode network (DMN) in normal aging and Alzheimer's disease (AD) using resting state fMRI at 3T. Images from young and elderly controls, and patients with AD were processed using spatial independent component analysis to identify the DMN. Functional connectivity was quantified using integration and indices derived from graph theory. Four DMN sub-systems were identified: Frontal (medial frontal, superior frontal), Parietal (precuneus-posterior cingulate, lateral parietal), Temporal (medial temporal cortices), and Hippocampal (left and right). There was a decrease in antero-posterior interactions (lower global efficiency), but increased interactions within the Frontal and Parietal sub-systems (higher local clustering) in elderly compared to young controls. The decreased antero-posterior integration was more pronounced in AD patients compared to elderly controls, particularly in the precuneus-posterior cingulate region. The approach allows for a complete characterization of connectivity changes and could be applied to other resting state networks and pathologies.
Posterior cingulate
Clustering coefficient
Cite
Citations (8)
The precuneus/posterior cingulate cortex, which has been associated with pain sensitivity, plays a pivotal role in the default mode network. However, information regarding migraine-related alterations in resting-state brain functional connectivity in the default mode network and in local regional spontaneous neuronal activity is not adequate. This study used functional magnetic resonance imaging to acquire resting-state scans in 22 migraineurs without aura and in 22 healthy matched controls. Independent component analysis, a data-driven method, was used to calculate the resting-state functional connectivity of the default mode network in the patient and healthy control groups. Regional homogeneity (ReHo) was used to analyse the local features of spontaneous resting-state brain activity in the migraineurs without aura. Compared with the healthy controls, migraineurs without aura showed increased functional connectivity in the left precuneus/posterior cingulate cortex within the default mode network and significant increase in ReHo values in the bilateral precuneus/posterior cingulate cortex, left pons and trigeminal nerve entry zone. In addition, functional connectivity was decreased between the areas with abnormal ReHo (using the peaks in the precuneus/posterior cingulate cortex) and other brain areas. The abnormalities in the precuneus/posterior cingulate cortex suggest that migraineurs without aura may exhibit information transfer and multimodal integration dysfunction and that pain sensitivity and pian processing may also be affected.
Posterior cingulate
Cingulate cortex
Cite
Citations (84)