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Normalized cut group clustering of resting-state FMRI data.

van den Heuvel M, Mandl R, Hulshoff Pol H - PLoS ONE (2008)

Bottom Line: Inter-voxel correlations of time-series are grouped at the individual level and the consistency of the resulting networks across subjects is clustered at the group level, defining the group RSNs.The 7 RSNs included motor/visual, auditory and attention networks and the frequently reported default mode network.The found RSNs showed large overlap with recently reported resting-state results and support the idea of the formation of spatially distinct RSNs during rest in the human brain.

View Article: PubMed Central - PubMed

Affiliation: Rudolf Magnus Institute of Neuroscience, Department of Psychiatry, University Medical Center Utrecht, Utrecht, The Netherlands. M.P.vandenheuvel@umcutrecht.nl

ABSTRACT

Background: Functional brain imaging studies have indicated that distinct anatomical brain regions can show coherent spontaneous neuronal activity during rest. Regions that show such correlated behavior are said to form resting-state networks (RSNs). RSNs have been investigated using seed-dependent functional connectivity maps and by using a number of model-free methods. However, examining RSNs across a group of subjects is still a complex task and often involves human input in selecting meaningful networks.

Methodology/principal findings: We report on a voxel based model-free normalized cut graph clustering approach with whole brain coverage for group analysis of resting-state data, in which the number of RSNs is computed as an optimal clustering fit of the data. Inter-voxel correlations of time-series are grouped at the individual level and the consistency of the resulting networks across subjects is clustered at the group level, defining the group RSNs. We scanned a group of 26 subjects at rest with a fast BOLD sensitive fMRI scanning protocol on a 3 Tesla MR scanner.

Conclusions/significance: An optimal group clustering fit revealed 7 RSNs. The 7 RSNs included motor/visual, auditory and attention networks and the frequently reported default mode network. The found RSNs showed large overlap with recently reported resting-state results and support the idea of the formation of spatially distinct RSNs during rest in the human brain.

Show MeSH
Group clustered resting-state networks.Group clustering of 3 Tesla resting-state fMRI data of a group of 26 subjects revealed 7 resting-state networks (RSNs). 1a shows a functional connected network consisting of the posterior cingulate/precuneus, medial frontal regions and bilateral parietal/temporal regions, a RSN known as the default mode network. 1b and 1c show lateralized parietal-frontal networks, networks that are often reported in attention and memory processing. 1d shows a joint network of both sensorimotor and visual networks. Iteratively clustering partitioned this cluster in 3 sub-clusters, shown in clustermap d'. The results showed separate clusters for primary visual regions (cluster d'-1), primary sensorimotor regions (cluster d'-2) and extra-striate visual regions (cluster d'-3). 1e shows a network of bilateral insular regions and posterior cingulate cortex. 1f and 1g represent singular clusters consisting of, respectively, a posterior part of Brodmann Area 7 and an anterior part of the cingulate cortex. The clustered networks show resemblance with previous reported RSNs.
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pone-0002001-g001: Group clustered resting-state networks.Group clustering of 3 Tesla resting-state fMRI data of a group of 26 subjects revealed 7 resting-state networks (RSNs). 1a shows a functional connected network consisting of the posterior cingulate/precuneus, medial frontal regions and bilateral parietal/temporal regions, a RSN known as the default mode network. 1b and 1c show lateralized parietal-frontal networks, networks that are often reported in attention and memory processing. 1d shows a joint network of both sensorimotor and visual networks. Iteratively clustering partitioned this cluster in 3 sub-clusters, shown in clustermap d'. The results showed separate clusters for primary visual regions (cluster d'-1), primary sensorimotor regions (cluster d'-2) and extra-striate visual regions (cluster d'-3). 1e shows a network of bilateral insular regions and posterior cingulate cortex. 1f and 1g represent singular clusters consisting of, respectively, a posterior part of Brodmann Area 7 and an anterior part of the cingulate cortex. The clustered networks show resemblance with previous reported RSNs.

Mentions: Spatial maps of the 7 clusters are shown in Figure 1 and can be described as follows. Cluster a (Figure 1a) shows a network of posterior cingulate/precuneus region (Brodmann Area (BA) 23/31), middle temporal gyrus (BA 39), inferior temporal gyrus (BA 21), supramarginal gyrus (BA 40) and frontal regions, including both superior frontal gyrus (BA 8) and medial frontal gyrus (BA 11). Clusters b and c (Figure 1b and 1c) show highly lateralized parietal-frontal networks in the left and right hemisphere, involving superior parietal lobule, inferior parietal lobule, supramarginal gyrus (BA 7/40), middle frontal gyrus and superior frontal gyrus (BA 8/9). Cluster d (Figure 1d) shows the largest found network, consisting of postcentral gyrus (BA 3/1/2), precentral gyrus (BA 4), cingulate gyrus (BA 24) and lateral, medial and superior occipital gyrus and peristriate region (BA 17/18/19). Cluster e (Figure 1e) involves bilateral insular and superior temporal cortex (BA 22) and a part of the cingulate gyrus (BA 24). Cluster f (Figure 1f) involves a singular region consisting of a posterior part of BA 7. Cluster g (Figure 1g) involves a singular region covering a medial part of the medial frontal gyrus (BA 9) and an anterior part of the cingulate gyrus (BA 32).


Normalized cut group clustering of resting-state FMRI data.

van den Heuvel M, Mandl R, Hulshoff Pol H - PLoS ONE (2008)

Group clustered resting-state networks.Group clustering of 3 Tesla resting-state fMRI data of a group of 26 subjects revealed 7 resting-state networks (RSNs). 1a shows a functional connected network consisting of the posterior cingulate/precuneus, medial frontal regions and bilateral parietal/temporal regions, a RSN known as the default mode network. 1b and 1c show lateralized parietal-frontal networks, networks that are often reported in attention and memory processing. 1d shows a joint network of both sensorimotor and visual networks. Iteratively clustering partitioned this cluster in 3 sub-clusters, shown in clustermap d'. The results showed separate clusters for primary visual regions (cluster d'-1), primary sensorimotor regions (cluster d'-2) and extra-striate visual regions (cluster d'-3). 1e shows a network of bilateral insular regions and posterior cingulate cortex. 1f and 1g represent singular clusters consisting of, respectively, a posterior part of Brodmann Area 7 and an anterior part of the cingulate cortex. The clustered networks show resemblance with previous reported RSNs.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2291558&req=5

pone-0002001-g001: Group clustered resting-state networks.Group clustering of 3 Tesla resting-state fMRI data of a group of 26 subjects revealed 7 resting-state networks (RSNs). 1a shows a functional connected network consisting of the posterior cingulate/precuneus, medial frontal regions and bilateral parietal/temporal regions, a RSN known as the default mode network. 1b and 1c show lateralized parietal-frontal networks, networks that are often reported in attention and memory processing. 1d shows a joint network of both sensorimotor and visual networks. Iteratively clustering partitioned this cluster in 3 sub-clusters, shown in clustermap d'. The results showed separate clusters for primary visual regions (cluster d'-1), primary sensorimotor regions (cluster d'-2) and extra-striate visual regions (cluster d'-3). 1e shows a network of bilateral insular regions and posterior cingulate cortex. 1f and 1g represent singular clusters consisting of, respectively, a posterior part of Brodmann Area 7 and an anterior part of the cingulate cortex. The clustered networks show resemblance with previous reported RSNs.
Mentions: Spatial maps of the 7 clusters are shown in Figure 1 and can be described as follows. Cluster a (Figure 1a) shows a network of posterior cingulate/precuneus region (Brodmann Area (BA) 23/31), middle temporal gyrus (BA 39), inferior temporal gyrus (BA 21), supramarginal gyrus (BA 40) and frontal regions, including both superior frontal gyrus (BA 8) and medial frontal gyrus (BA 11). Clusters b and c (Figure 1b and 1c) show highly lateralized parietal-frontal networks in the left and right hemisphere, involving superior parietal lobule, inferior parietal lobule, supramarginal gyrus (BA 7/40), middle frontal gyrus and superior frontal gyrus (BA 8/9). Cluster d (Figure 1d) shows the largest found network, consisting of postcentral gyrus (BA 3/1/2), precentral gyrus (BA 4), cingulate gyrus (BA 24) and lateral, medial and superior occipital gyrus and peristriate region (BA 17/18/19). Cluster e (Figure 1e) involves bilateral insular and superior temporal cortex (BA 22) and a part of the cingulate gyrus (BA 24). Cluster f (Figure 1f) involves a singular region consisting of a posterior part of BA 7. Cluster g (Figure 1g) involves a singular region covering a medial part of the medial frontal gyrus (BA 9) and an anterior part of the cingulate gyrus (BA 32).

Bottom Line: Inter-voxel correlations of time-series are grouped at the individual level and the consistency of the resulting networks across subjects is clustered at the group level, defining the group RSNs.The 7 RSNs included motor/visual, auditory and attention networks and the frequently reported default mode network.The found RSNs showed large overlap with recently reported resting-state results and support the idea of the formation of spatially distinct RSNs during rest in the human brain.

View Article: PubMed Central - PubMed

Affiliation: Rudolf Magnus Institute of Neuroscience, Department of Psychiatry, University Medical Center Utrecht, Utrecht, The Netherlands. M.P.vandenheuvel@umcutrecht.nl

ABSTRACT

Background: Functional brain imaging studies have indicated that distinct anatomical brain regions can show coherent spontaneous neuronal activity during rest. Regions that show such correlated behavior are said to form resting-state networks (RSNs). RSNs have been investigated using seed-dependent functional connectivity maps and by using a number of model-free methods. However, examining RSNs across a group of subjects is still a complex task and often involves human input in selecting meaningful networks.

Methodology/principal findings: We report on a voxel based model-free normalized cut graph clustering approach with whole brain coverage for group analysis of resting-state data, in which the number of RSNs is computed as an optimal clustering fit of the data. Inter-voxel correlations of time-series are grouped at the individual level and the consistency of the resulting networks across subjects is clustered at the group level, defining the group RSNs. We scanned a group of 26 subjects at rest with a fast BOLD sensitive fMRI scanning protocol on a 3 Tesla MR scanner.

Conclusions/significance: An optimal group clustering fit revealed 7 RSNs. The 7 RSNs included motor/visual, auditory and attention networks and the frequently reported default mode network. The found RSNs showed large overlap with recently reported resting-state results and support the idea of the formation of spatially distinct RSNs during rest in the human brain.

Show MeSH