Widespread functional disconnectivity in schizophrenia with resting-state functional magnetic resonance imaging

Liang, Meng; Zhou, Yuan; Jiang, Tianzi; Liu, Zhening; Tian, Lihong; Liu, Haihong; Hao, Yihui

doi:10.1097/01.wnr.0000198434.06518.b8

Cited by 368 publications

(287 citation statements)

References 23 publications

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“…A recent functional connectivity study examined fMRI timeseries correlations between all combinations of 116 brain regions and found that, except for increased cerebellar connectivity, schizophrenia subjects in a resting state exhibited global reductions in functional connectivity (Liang et al, 2006). Other studies using timeseries correlations have focused on different specific connections, and identified abnormalities in the connectivity of the cerebellum (Stephan et al, 2001) and anterior cingulate (Honey et al, 2005).…”

Section: Discussionmentioning

confidence: 99%

Alterations of fronto-temporal connectivity during word encoding in schizophrenia

Wolf

Gur

Valdez

et al. 2007

Psychiatry Research: Neuroimaging

106

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Cognitive deficits, including impaired verbal memory, are prominent in schizophrenia and lead to increased disability. Functional neuroimaging of patients with schizophrenia performing memory tasks has revealed abnormal activation patterns in prefrontal cortex and temporo-limbic regions. Aberrant fronto-temporal interactions thus represent a potential pathophysiological mechanism underlying verbal memory deficits, yet this hypothesis of disturbed connectivity is not tested directly with standard activation studies. We performed within-subject correlations of frontal and temporal timeseries to measure functional connectivity during verbal encoding. Our results confirm earlier findings of aberrant fronto-temporal connectivity in schizophrenia, and extend them by identifying distinct alterations within dorsal and ventral prefrontal cortex. Relative to healthy controls, patients with schizophrenia had reduced connectivity between the dorsolateral prefrontal cortex (DLPFC) and temporal lobe areas including parahippocampus and superior temporal gyrus. In contrast, patients showed increased connectivity between a region of ventrolateral prefrontal cortex (VLPFC) and these same temporal lobe regions. Higher temporal-DLPFC connectivity during encoding was associated with better subsequent recognition accuracy in controls, but not patients. Temporal-VLPFC connectivity was uncorrelated with recognition accuracy in either group. The results suggest that reduced temporal-DLPFC connectivity in schizophrenia could underlie encoding deficits, and increased temporal-VLPFC connectivity may represent an ineffective compensatory effort.

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Section: Discussionmentioning

confidence: 99%

Alterations of fronto-temporal connectivity during word encoding in schizophrenia

Wolf

Gur

Valdez

et al. 2007

Psychiatry Research: Neuroimaging

106

View full text Add to dashboard Cite

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“…The activity is similar to that observed during stimulus presentation (1,(6)(7)(8), incorporates previously acquired information (9), and carries information about the underlying neuronal network [for review see (10)]. Indeed, correlations during resting state activity are altered in disease states such as schizophrenia or chronic pain (11,12), which raises the question whether there is a general framework that describes the statistics in the spatiotemporal organization of this dynamics.…”

mentioning

confidence: 97%

Spontaneous cortical activity in awake monkeys composed of neuronal avalanches

Petermann

Thiagarajan

Lebedev

et al. 2009

Proc. Natl. Acad. Sci. U.S.A.

517

530

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Spontaneous neuronal activity is an important property of the cerebral cortex but its spatiotemporal organization and dynamical framework remain poorly understood. Studies in reduced systems-tissue cultures, acute slices, and anesthetized ratsshow that spontaneous activity forms characteristic clusters in space and time, called neuronal avalanches. Modeling studies suggest that networks with this property are poised at a critical state that optimizes input processing, information storage, and transfer, but the relevance of avalanches for fully functional cerebral systems has been controversial. Here we show that ongoing cortical synchronization in awake rhesus monkeys carries the signature of neuronal avalanches. Negative LFP deflections (nLFPs) correlate with neuronal spiking and increase in amplitude with increases in local population spike rate and synchrony. These nLFPs form neuronal avalanches that are scale-invariant in space and time and with respect to the threshold of nLFP detection. This dimension, threshold invariance, describes a fractal organization: smaller nLFPs are embedded in clusters of larger ones without destroying the spatial and temporal scale-invariance of the dynamics. These findings suggest an organization of ongoing cortical synchronization that is scale-invariant in its three fundamental dimensions-time, space, and local neuronal group size. Such scale-invariance has ontogenetic and phylogenetic implications because it allows large increases in network capacity without a fundamental reorganization of the system. neuronal synchronization ͉ resting state ͉ rhesus monkey ͉ spontaneous activity ͉ ongoing activity T he cerebral cortex displays spontaneous activity, also known as 'ongoing' or 'resting state' activity, which persists in the absence of sensory stimuli or motor outputs. The ongoing activity is a robust feature of cortical dynamics as it is only modulated to a small extent by stimulus presentation (1), but contributes significantly to the large variability observed in stimulus responses (2-5). In fact, ongoing activity has been found to reflect multiple aspects of neuronal processing. The activity is similar to that observed during stimulus presentation (1, 6-8), incorporates previously acquired information (9), and carries information about the underlying neuronal network [for review see (10)]. Indeed, correlations during resting state activity are altered in disease states such as schizophrenia or chronic pain (11, 12), which raises the question whether there is a general framework that describes the statistics in the spatiotemporal organization of this dynamics.Recently, we found that spontaneous cortical activity in slice cultures, acute slices, and in the anesthetized rat in vivo has a scale-invariant dynamics called neuronal avalanches (13)(14)(15). These spontaneous bursts of synchronized activity occur in clusters of sizes s (where s is the number of active sites in an electrode array) that distribute according to a power law with exponent ␣:where ␣ usually lies between ...

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“…Although brain functions proposed for the DMN are impaired in patients with schizophrenia (Buckner et al, 2008), neuroimaging studies have reported inconsistent findings in the DMN of these individuals. Increased (Garrity et al, 2007;Harrison et al, 2007;Whitfield-Gabrieli et al, 2009;Zhou et al, 2007) or decreased (Liang et al, 2006;Pomarol-Clotet et al, 2008) activity and connectivity have been reported in the DMN network at the level of individual regions as well as of the global network. Different issues may have contributed to lack of consistent findings, including the method used for estimation of connectivity (Murphy et al, 2009).…”

Section: Introductionmentioning

confidence: 99%

Treatment with Olanzapine is Associated with Modulation of the Default Mode Network in Patients with Schizophrenia

Sambataro

Blasi

Fazio

et al. 2009

Neuropsychopharmacol

177

128

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Earlier studies have shown widespread alterations of functional connectivity of various brain networks in schizophrenia, including the default mode network (DMN). The DMN has also an important role in the performance of cognitive tasks. Furthermore, treatment with second-generation antipsychotic drugs may ameliorate to some degree working memory (WM) deficits and related brain activity. The aim of this study was to evaluate the effects of treatment with olanzapine monotherapy on functional connectivity among brain regions of the DMN during WM. Seventeen patients underwent an 8-week prospective study and completed two functional magnetic resonance imaging (fMRI) scans at 4 and 8 weeks of treatment during the performance of the N-back WM task. To control for potential repetition effects, 19 healthy controls also underwent two fMRI scans at a similar time interval. We used spatial group-independent component analysis (ICA) to analyze fMRI data. Relative to controls, patients with schizophrenia had reduced connectivity strength within the DMN in posterior cingulate, whereas it was greater in precuneus and inferior parietal lobule. Treatment with olanzapine was associated with increases in DMN connectivity with ventromedial prefrontal cortex, but not in posterior regions of DMN. These results suggest that treatment with olanzapine is associated with the modulation of DMN connectivity in schizophrenia. In addition, our findings suggest critical functional differences in the regions of DMN.

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Widespread functional disconnectivity in schizophrenia with resting-state functional magnetic resonance imaging

Cited by 368 publications

References 23 publications

Alterations of fronto-temporal connectivity during word encoding in schizophrenia

Alterations of fronto-temporal connectivity during word encoding in schizophrenia

Spontaneous cortical activity in awake monkeys composed of neuronal avalanches

Treatment with Olanzapine is Associated with Modulation of the Default Mode Network in Patients with Schizophrenia

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