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1
Combining transcranial magnetic stimulation and FMRI to examine the default mode network.
2010-12-28

The default mode network is a group of brain regions that are active when an individual is not focused on the outside world and the brain is at "wakeful rest." It is thought the default mode network corresponds to self-referential or "internal mentation". It has been ...

PubMed

2
Functional resting-state networks are differentially affected in schizophrenia.
2011-03-31

Neurobiological theories posit that schizophrenia relates to disturbances in connectivity between brain regions. Resting-state functional magnetic resonance imaging is a powerful tool for examining functional connectivity and has revealed several canonical brain networks, including the default mode, dorsal attention, executive control, ...

PubMed

3
Default mode network functional and structural connectivity after traumatic brain injury.
2011-08-01

Traumatic brain injury often results in cognitive impairments that limit recovery. The underlying pathophysiology of these impairments is uncertain, which restricts clinical assessment and management. Here, we use magnetic resonance imaging to test the hypotheses that: (i) traumatic brain injury results in abnormalities of functional connectivity within key cognitive ...

PubMed

4
Resting state fMRI in Alzheimer's disease: beyond the default mode network.
2011-08-01

Using resting state (RS) functional magnetic resonance imaging (fMRI), the connectivity patterns of the default mode (DMN), frontoparietal, executive, and salience networks were explored in 13 Alzheimer's disease (AD) patients, 12 amnestic mild cognitive impairment (aMCI) patients, and 13 healthy controls. Compared with controls and ...

PubMed

5
Modulating spontaneous brain activity using repetitive transcranial magnetic stimulation
2010-11-10

BackgroundWhen no specific stimulus or task is presented, spontaneous fluctuations in brain activity occur. Brain regions showing such coherent fluctuations are thought to form organized networks known as 'resting-state' networks, a main representation of which is the default mode network. ...

PubMed Central

6
Failure to segregate emotional processing from cognitive and sensorimotor processing in major depression.
2011-07-20

Most functional neuroimaging studies of major depressive disorder (MDD) employ univariate methods of statistical analysis to localize abnormalities of neural activity. Less has been done to investigate functional relations between these regions, or with regions not usually implicated in depression. Examination of intraneuronal and interneural network ...

PubMed

7
Functional connectivity tracks clinical deterioration in Alzheimer's disease.
2011-08-13

While resting state functional connectivity has been shown to decrease in patients with mild and/or moderate Alzheimer's disease, it is not yet known how functional connectivity changes in patients as the disease progresses. Furthermore, it has been noted that the default mode network is not as homogenous as previously assumed and ...

PubMed

8
Default-mode network connectivity and white matter burden in late-life depression.
2011-08-01

The brain's default-mode network has been the focus of intense research. This study characterizes the default-mode network activity in late-life depression and the correlation of the default-mode network activity changes with the white-matter hyperintensities burden. We hypothesized that elderly depressed subjects ...

PubMed

9
Abnormal functional connectivity of default mode sub-networks in autism spectrum disorder patients
2010-06-02

Autism spectrum disorders (ASDs) are characterized by deficits in social and communication processes. Recent data suggest that altered functional connectivity (FC), i.e. synchronous brain activity, might contribute to these deficits. Of specific interest is the FC integrity of the default mode network (DMN), a ...

PubMed Central

10
Modulation of steady state functional connectivity in the default mode and working memory networks by cognitive load.
2010-11-12

Interregional correlations between blood oxygen level dependent (BOLD) magnetic resonance imaging (fMRI) signals in the resting state have been interpreted as measures of connectivity across the brain. Here we investigate whether such connectivity in the working memory and default mode networks is modulated by changes in cognitive ...

PubMed

11
Combining spatial and temporal information to explore resting-state networks changes in abstinent heroin-dependent individuals.
2010-03-17

Majority of previous heroin fMRI studies focused on abnormal brain function in heroin-dependent individuals. However, few fMRI studies focused on the resting-state abnormalities in heroin-dependent individuals and assessed the relationship between the resting-state functional connectivity changes and duration of heroin use. In the present study, discrete ...

PubMed

12
The Effect of Respiration Variations on Independent Component Analysis Results of Resting State Functional Connectivity
2008-07-01

The analysis of functional connectivity in fMRI can be severely affected by cardiac and respiratory fluctuations. While some of these artifactual signal changes can be reduced by physiological noise correction routines, signal fluctuations induced by slower breath-to-breath changes in the depth and rate of breathing are typically not removed. These slower respiration-induced signal changes occur ...

PubMed Central

13
Altered resting-state connectivity in subjects at ultra-high risk for psychosis: an fMRI study
2010-10-11

BackgroundIndividuals at ultra-high risk (UHR) for psychosis have self-disturbances and deficits in social cognition and functioning. Midline default network areas, including the medial prefrontal cortex and posterior cingulate cortex, are implicated in self-referential and social cognitive tasks. Thus, the neural substrates within the default ...

PubMed Central

14
Altered functional connectivity in default mode network in absence epilepsy: a resting-state fMRI study.
2011-03-01

Dysfunctional default mode network (DMN) has been observed in various mental disorders, including epilepsy (see review Broyd et al. [2009]: Neurosci Biobehav Rev 33:279�296). Because interictal epileptic discharges may affect DMN, resting-state fMRI was used in this study to determine DMN functional connectivity in 14 healthy ...

PubMed

15
Abnormal Brain Default-Mode Network Functional Connectivity in Drug Addicts
2011-01-26

BackgroundThe default mode network (DMN) is a set of brain regions that exhibit synchronized low frequency oscillations at resting-state, and is believed to be relevant to attention and self-monitoring. As the anterior cingulate cortex and hippocampus are impaired in drug addiction and meanwhile are parts of the DMN, the present study ...

PubMed Central

16
The default mode network and altered consciousness in epilepsy
2011-01-01

The default mode network has been hypothesized following the observation that specific regions of the brain are consistently activated during the resting state and deactivated during engagement with task. The primary nodes of this network, which typically include the precuneus / posterior cingulate, the medial ...

PubMed Central

17
Medial prefrontal cortex pathology in schizophrenia as revealed by convergent findings from multimodal imaging.
2010-01-12

Neuroimaging studies have found evidence of altered brain structure and function in schizophrenia, but have had complex findings regarding the localization of abnormality. We applied multimodal imaging (voxel-based morphometry (VBM), functional magnetic resonance imaging (fMRI) and diffusion tensor imaging (DTI) combined with tractography) to 32 chronic schizophrenic patients ...

PubMed

18
Medial prefrontal cortex pathology in schizophrenia as revealed by convergent findings from multimodal imaging
2010-08-12

Neuroimaging studies have found evidence of altered brain structure and function in schizophrenia, but have had complex findings regarding the localization of abnormality. We applied multimodal imaging (voxel-based morphometry (VBM), functional magnetic resonance imaging (fMRI) and diffusion tensor imaging (DTI) combined with tractography) to 32 chronic schizophrenic patients ...

PubMed Central

19
Beyond amygdala: Default Mode Network activity differs between patients with social phobia and healthy controls.
2009-02-20

The Default Mode Network (DMN) is a constellation of brain areas that decrease their activity during a wide number of different goal-oriented tasks as compared to passive "rest" tasks. DMN can be modulated by different factors such as emotional states, cognitive load of the task and psychopathology, including anxiety. Moreover, DMN ...

PubMed

20
Decreased Default Mode Neural Network Modulation with Age in Schizophrenia
2010-10-01

ObjectivePrevious studies have shown that patients with schizophrenia have less modulation of the task-positive and default mode networks of the brain during novelty detection. To date, the relationship between network modulation and age has not been assessed in patients with a long duration of ...

PubMed Central

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21
Lateral differences in the default mode network in healthy controls and patients with schizophrenia.
2011-04-01

We investigate lateral differences in the intrinsic fluctuations comprising the default mode network (DMN) for healthy controls (HCs) and patients with schizophrenia (SZ), both during rest and during an auditory oddball (AOD) task. Our motivation for this study comes from multiple prior hypotheses of disturbed hemispheric asymmetry in ...

PubMed

22
Lateral Differences in the Default Mode Network in Healthy Controls and Schizophrenia Patients
2011-04-01

We investigate lateral differences in the intrinsic fluctuations comprising the default mode network (DMN) for healthy controls (HC) and patients with schizophrenia (SZ), both during rest and during an auditory oddball (AOD) task. Our motivation for this study comes from multiple prior hypotheses of disturbed hemispheric asymmetry in ...

PubMed Central

23
Default Mode Network Connectivity Predicts Sustained Attention Deficits after Traumatic Brain Injury.
2011-09-21

Traumatic brain injury (TBI) frequently produces impairments of attention in humans. These can result in a failure to maintain consistent goal-directed behavior. A predominantly right-lateralized frontoparietal network is often engaged during attentionally demanding tasks. However, lapses of attention have also been associated with increases in activation within the ...

PubMed

24
Sustained activity within the default mode network during an implicit memory task
2009-05-18

Recent neuroimaging studies have shown that several brain regions -- namely, the posterior cingulate cortex (PCC), ventral medial prefrontal cortex (vmPFC), and the bilateral angular gyrus -- are more active during resting states than during cognitive tasks (i.e., default mode network). Although there is evidence showing that the ...

PubMed Central

25
[Default mode network of the brain : Neurobiology and clinical significance.
2011-05-18

The resting state of the human brain is intrinsically organized by the so-called default mode network (DMN) which comprises cortical midline structure as well as lateral parietal and temporal areas. The activity of this system increases during self-oriented thinking, e.g. during a resting state but decreases during externally oriented ...

PubMed

26
Multivariate Searchlight Classification of Structural Magnetic Resonance Imaging in Children and Adolescents with Autism.
2011-09-01

BACKGROUND: Autism spectrum disorders (ASD) are neurodevelopmental disorders with a prevalence of nearly 1:100. Structural imaging studies point to disruptions in multiple brain areas, yet the precise neuroanatomical nature of these disruptions remains unclear. Characterization of brain structural differences in children with ASD is critical for development of biomarkers that may eventually be ...

PubMed

27
Default mode network abnormalities in mesial temporal lobe epilepsy: a study combining fMRI and DTI.
2010-06-09

Studies of in mesial temporal lobe epilepsy (mTLE) patients with hippocampal sclerosis (HS) have reported reductions in both functional and structural connectivity between hippocampal structures and adjacent brain regions. However, little is known about the connectivity among the default mode network (DMN) in mTLE. Here, we ...

PubMed

28
Functional phenotyping of successful aging in long-term memory: Preserved performance in the absence of neural compensation.
2010-07-21

We investigated whether preservation of encoding-related brain activity patterns in older age reflects successful aging in long-term memory. Using a statistical matching technique, we identified groups of healthy older adults with different degrees of Functional Activity Deviation during Encoding (FADE) from young adults in a memory network comprising hippocampal, temporal, ...

PubMed

29
Altered cortical-cerebellar circuits during verbal working memory in essential tremor.
2011-07-11

Essential tremor is a common neurological disorder characterized by motor and cognitive symptoms including working memory deficits. Epidemiological research has shown that patients with essential tremor are at a higher risk to develop dementia relative to age-matched individuals; this demonstrates that cognitive impairments reflect specific, although poorly understood, disease mechanisms. ...

PubMed

30
Evidence for Anomalous Network Connectivity during Working Memory Encoding in Schizophrenia: An ICA Based Analysis
2009-11-19

BackgroundNumerous neuroimaging studies report abnormal regional brain activity during working memory performance in schizophrenia, but few have examined brain network integration as determined by �functional connectivity� analyses.Methodology/Principal FindingsWe used independent component analysis (ICA) to identify and characterize dysfunctional ...

PubMed Central

31
The unrested resting brain: sleep deprivation alters activity within the default-mode network.
2010-08-01

The sleep-deprived brain has principally been characterized by examining dysfunction during cognitive task performance. However, far less attention has been afforded the possibility that sleep deprivation may be as, if not more, accurately characterized on the basis of abnormal resting-state brain activity. Here we report that one night of sleep deprivation significantly ...

PubMed

32
The un-rested resting brain: Sleep-deprivation alters activity within the default-mode network
2010-08-01

The sleep-deprived brain has principally been characterized by examining dysfunction during cognitive-task performance. However, far less attention has been afforded the possibility that sleep deprivation may be as, if not more, accurately characterized on the basis of abnormal resting-state brain activity. Here we report that one night of sleep deprivation significantly ...

PubMed Central

33
Neural connectivity as an intermediate phenotype: brain networks under genetic control.
2009-07-01

Recent evidence suggests that default mode connectivity characterizes neural states that account for a sizable proportion of brain activity and energy expenditure, and therefore represent a plausible neural intermediate phenotype. This implies the possibility of genetic control over systems-level connectivity features. Imaging genetics is an approach to ...

PubMed

34
Genetic control over the resting brain
2010-01-19

The default-mode network, a coherent resting-state brain network, is thought to characterize basal neural activity. Aberrant default-mode connectivity has been reported in a host of neurological and psychiatric illnesses and in persons at genetic risk for such illnesses. Whereas the neurophysiologic mechanisms that regulate ...

PubMed Central

35
The Integration of Prosodic Speech in High Functioning Autism: A Preliminary fMRI Study
2010-07-13

BackgroundAutism is a neurodevelopmental disorder characterized by a specific triad of symptoms such as abnormalities in social interaction, abnormalities in communication and restricted activities and interests. While verbal autistic subjects may present a correct mastery of the formal aspects of speech, they have difficulties in prosody (music of ...

PubMed Central

36
Default Mode Network Abnormalities in Bipolar Disorder and Schizophrenia
2010-06-09

The default-mode network (DMN) consists of a set of brain areas preferentially activated during internally focused tasks. We used functional MRI to study the DMN in bipolar mania and acute schizophrenia. 17 bipolar disorder (BD), 14 schizophrenia (SZ) and 15 normal control (NC) subjects underwent 10-minute resting scans. The DMN was extracted using independent component ...

PubMed Central

37
Functional connectivity in fronto-subcortical circuitry during the resting state in obsessive-compulsive disorder.
2010-03-17

Obsessions and compulsions mediated by cognitive inflexibility might be associated with abnormal resting state functional connectivity in the default mode network (DMN) that represents intrinsically generated neuronal activity. It was hypothesized that decreased functional connectivity in the DMN would occur in ...

PubMed

38
The default mode network in healthy aging and Alzheimer's disease.
2011-06-14

In the past decade, a "default mode network" (DMN) has been highlighted in neuroimaging studies as a set of brain regions showing increased activity in task-free state compared to cognitively demanding task, and synchronized activity at rest. Changes within this network have been described in healthy aging as well ...

PubMed

39
The Default Mode Network in Healthy Aging and Alzheimer's Disease
2011-06-14

In the past decade, a �default mode network� (DMN) has been highlighted in neuroimaging studies as a set of brain regions showing increased activity in task-free state compared to cognitively demanding task, and synchronized activity at rest. Changes within this network have been described in healthy aging as ...

PubMed Central

40
Decoupling of the brain's default mode network during deep sleep
2009-07-07

The recent discovery of a circuit of brain regions that is highly active in the absence of overt behavior has led to a quest for revealing the possible function of this so-called default-mode network (DMN). A very recent study, finding similarities in awake humans and anesthetized primates, has suggested that DMN activity might not simply reflect ongoing ...

PubMed Central

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41
Strength of default mode resting state connectivity relates to white matter integrity in children
2010-12-09

A default mode network of brain regions is known to demonstrate coordinated activity during the resting state. While the default mode network is well characterized in adults, few investigations have focused upon its development. We scanned 9�13 year old children with ...

PubMed Central

42
Strength of Default Mode Resting-State Connectivity Relates to White Matter Integrity in Children
2011-07-01

A default mode network of brain regions is known to demonstrate coordinated activity during the resting state. While the default mode network is well characterized in adults, few investigations have focused upon its development. We scanned 9-13-year-old children with ...

ERIC Educational Resources Information Center

43
Full-brain auto-regressive modeling (FARM) using fMRI.
2011-03-22

In order to fully uncover the information potentially available in the fMRI signal, we model it as a multivariate auto-regressive process. To infer the model, we do not apply any form of clustering or dimensionality reduction, and solve the problem of under-determinacy using sparse regression. We find that only a few small clusters (with average size of 3-4 voxels) are useful in predicting the ...

PubMed

44
Default-Mode Network Activity Identified by Group Independent Component Analysis
2007-01-01

Default-mode network activity refers to some regional increase in blood oxygenation level-dependent (BOLD) signal during baseline than cognitive tasks. Recent functional imaging studies have found co-activation in a distributed network of cortical regions, including ventral anterior cingulate cortex (vACC) and posterior cingulate ...

NASA Astrophysics Data System (ADS)

45
Aberrant connectivity of resting-state networks in borderline personality disorder.
2011-03-01

Background: Several functional neuroimaging studies have reported regionally abnormal activation of the frontal cortex in individuals with borderline personality disorder (BPD) during cognitive and affective task performance. However, little is known about neural function in individuals with BPD during the resting state. Using functional magnetic resonance imaging (fMRI), this ...

PubMed

46
Antipsychotic Dose and Diminished Neural Modulation: A Multi-Site fMRI Study
2010-12-23

BackgroundThe effect of antipsychotics on the blood oxygen level dependent signal in schizophrenia is poorly understood. The purpose of the present investigation is to examine the effect of type (typical or atypical) and dose of antipsychotic medication on independent neural networks during a motor task in a large, multi-site functional magnetic resonance imaging ...

PubMed Central

47
Task-Related Default Mode Network Modulation and Inhibitory Control in ADHD: Effects of Motivation and Methylphenidate
2011-07-01

Background: Deficits characteristic of attention deficit/hyperactivity disorder (ADHD), including poor attention and inhibitory control, are at least partially alleviated by factors that increase engagement of attention, suggesting a hypodopaminergic reward deficit. Lapses of attention are associated with attenuated deactivation of the default mode ...

ERIC Educational Resources Information Center

48
Associations and dissociations between default and self-reference networks in the human brain.
2010-11-25

Neuroimaging has revealed consistent activations in medial prefrontal cortex (MPFC) and posterior cingulate cortex (PCC) extending to precuneus both during explicit self-reference tasks and during rest, a period during which some form of self-reference is assumed to occur in the default mode of brain function. The similarity between these two patterns of ...

PubMed

49
Switching between executive and default mode networks in posttraumatic stress disorder: alterations in functional connectivity
2010-07-01

BackgroundWorking memory processing and resting-state connectivity in the default mode network are altered in patients with post-traumatic stress disorder (PTSD). Because the ability to effortlessly switch between concentration on a task and an idling state during rest is implicated in both these alterations, we undertook a functional ...

PubMed Central

50
Divergent network connectivity changes in behavioural variant frontotemporal dementia and Alzheimer�s disease
2010-05-21

Resting-state or intrinsic connectivity network functional magnetic resonance imaging provides a new tool for mapping large-scale neural network function and dysfunction. Recently, we showed that behavioural variant frontotemporal dementia and Alzheimer�s disease cause atrophy within two major networks, an anterior �Salience ...

PubMed Central

51
Hyperactivity and hyperconnectivity of the default network in schizophrenia and in first-degree relatives of persons with schizophrenia
2009-01-27

We examined the status of the neural network mediating the default mode of brain function, which typically exhibits greater activation during rest than during task, in patients in the early phase of schizophrenia and in young first-degree relatives of persons with schizophrenia. During functional MRI, patients, relatives, and controls ...

PubMed Central

52
Cooperation between the default mode network and the frontal-parietal network in the production of an internal train of thought.
2011-04-01

The ability to generate and sustain an internal train of thought unrelated to external reality frees an agent from the constraints of only acting on immediate, environmentally triggered events. The current paper proposes that such thought is produced through cooperation between autobiographical information provided by the default mode ...

PubMed

53
Motor system hyperconnectivity in juvenile myoclonic epilepsy: a cognitive functional magnetic resonance imaging study.
2011-06-01

Juvenile myoclonic epilepsy is the most frequent idiopathic generalized epilepsy syndrome. It is characterized by predominant myoclonic jerks of upper limbs, often provoked by cognitive activities, and typically responsive to treatment with sodium valproate. Neurophysiological, neuropsychological and imaging studies in juvenile myoclonic epilepsy have consistently pointed towards subtle ...

PubMed

54
Motor system hyperconnectivity in juvenile myoclonic epilepsy: a cognitive functional magnetic resonance imaging study
2011-06-24

Juvenile myoclonic epilepsy is the most frequent idiopathic generalized epilepsy syndrome. It is characterized by predominant myoclonic jerks of upper limbs, often provoked by cognitive activities, and typically responsive to treatment with sodium valproate. Neurophysiological, neuropsychological and imaging studies in juvenile myoclonic epilepsy have consistently pointed towards subtle ...

PubMed Central

55
L-Dopa Modulates Functional Connectivity in Striatal Cognitive and Motor Networks: A Double-Blind Placebo-Controlled Study
2009-06-03

Functional connectivity (FC) analyses of resting-state fMRI data allow for the mapping of large-scale functional networks, and provide a novel means of examining the impact of dopaminergic challenge. Here, using a double-blind, placebo-controlled design, we examined the effect of L-dopa, a dopamine precursor, on striatal resting-state FC in 19 healthy young adults. We examined ...

PubMed Central

56
Effective connectivity analysis of default mode network based on the Bayesian network learning approach
2009-02-01

This work proposed to use the linear Gaussian Bayesian network (BN) to construct the effective connectivity model of the brain's default mode network (DMN), a set of regions characterized by more increased neural activity during rest-state than most goal-oriented tasks. In a complete unsupervised data-driven ...

NASA Astrophysics Data System (ADS)

57
Is Social Phobia a �Mis-Communication� Disorder? Brain Functional Connectivity during Face Perception Differs between Patients with Social Phobia and Healthy Control Subjects
2010-11-22

Recently, a differential recruitment of brain areas throughout the distributed neural system for face perception has been found in social phobic patients as compared to healthy control subjects. These functional abnormalities in social phobic patients extend beyond emotion-related brain areas, such as the amygdala, to include cortical networks that ...

PubMed Central

58
Is Social Phobia a "Mis-Communication" Disorder? Brain Functional Connectivity during Face Perception Differs between Patients with Social Phobia and Healthy Control Subjects.
2010-11-22

Recently, a differential recruitment of brain areas throughout the distributed neural system for face perception has been found in social phobic patients as compared to healthy control subjects. These functional abnormalities in social phobic patients extend beyond emotion-related brain areas, such as the amygdala, to include cortical networks that ...

PubMed

59
Topographic maps of multisensory attention.
2010-11-01

The intraparietal sulcus (IPS) region is uniquely situated at the intersection of visual, somatosensory, and auditory association cortices, ideally located for processing of multisensory attention. We examined the internal architecture of the IPS region and its connectivity to other regions in the dorsal attention and cinguloinsular networks using maximal connectivity ...

PubMed

60
Topographic maps of multisensory attention
2010-11-16

The intraparietal sulcus (IPS) region is uniquely situated at the intersection of visual, somatosensory, and auditory association cortices, ideally located for processing of multisensory attention. We examined the internal architecture of the IPS region and its connectivity to other regions in the dorsal attention and cinguloinsular networks using maximal connectivity ...

PubMed Central

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61
Minimum spanning tree reflects the alterations of the default mode network during Alzheimer's disease.
2011-02-01

This study analyzes the connectivity pattern of the default mode network (DMN) in patients with Alzheimer's disease (AD) in comparison with young and elderly controls using the minimum spanning tree (MST). This tree is a tool from graph theory and connects all the nodes of a graph with the minimum cost. The findings revealed that the ...

PubMed

62
Activation of the Occipital Cortex and Deactivation of the Default Mode Network During Working Memory in the Early Blind.
2011-02-22

Although blind people heavily depend on working memory to manage daily life without visual information, it is not clear yet whether their working memory processing involves functional reorganization of the memory-related cortical network. To explore functional reorganization of the cortical network that supports various types of working memory processes in ...

PubMed

63
Sleep deprivation reduces default mode network connectivity and anti-correlation during rest and task performance.
2011-08-18

Sleep deprivation (SD) can alter extrinsic, task-related fMRI signal involved in attention, memory and executive function. However, its effects on intrinsic low-frequency connectivity within the Default Mode Network (DMN) and its related anti-correlated network (ACN) have not been well characterized. We ...

PubMed

64
Patterns of brain activity supporting autobiographical memory, prospection, and theory of mind, and their relationship to the default mode network.
2010-06-01

The ability to rise above the present environment and reflect upon the past, the future, and the minds of others is a fundamentally defining human feature. It has been proposed that these three self-referential processes involve a highly interconnected core set of brain structures known as the default mode network (DMN). The DMN ...

PubMed

65
Multimodal Imaging of Alzheimer Pathophysiology in the Brain's Default Mode Network
2011-04-19

The spatial correlations between the brain's default mode network (DMN) and the brain regions known to develop pathophysiology in Alzheimer's disease (AD) have recently attracted much attention. In this paper, we compare results of different functional and structural imaging modalities, including MRI and PET, and highlight different ...

PubMed Central

66
Are posterior default-mode networks more robust than anterior default-mode networks? Evidence from resting-state fMRI data analysis.
2011-05-06

Intrinsic brain activity known as default-mode networks (DMNs) has been observed predominantly within the medial/superior frontal areas, anterior/posterior cingulate gyri, and precuneus using blood-oxygenation-level-dependent (BOLD) functional MRI (fMRI). Despite anecdotal evidence of distinct spatial patterns reflecting neuropsychiatric conditions in these DMNs, rigorous ...

PubMed

67
Mind wandering and attention during focused meditation: A fine-grained temporal analysis of fluctuating cognitive states.
2011-07-14

Studies have suggested that the default mode network is active during mind wandering, which is often experienced intermittently during sustained attention tasks. Conversely, an anticorrelated task-positive network is thought to subserve various forms of attentional processing. Understanding how these two systems ...

PubMed

68
Inter-Individual Differences in Resting State Functional Connectivity Predict Task-Induced BOLD Activity
2010-01-15

The resting brain exhibits coherent patterns of spontaneous low-frequency BOLD fluctuations. These so-called resting-state functional connectivity (RSFC) networks are posited to reflect intrinsic representations of functional systems commonly implicated in cognitive function. Yet, the direct relationship between RSFC and the BOLD response induced by task performance remains ...

PubMed Central

69
High-field MRI reveals an acute impact on brain function in survivors of the magnitude 8.0 earthquake in China.
2009-08-31

Besides the enormous medical and economic consequences, national disasters, such as the Wenchuan 8.0 earthquake, also pose a risk to the mental health of survivors. In this context, a better understanding is needed of how functional brain systems adapt to severe emotional stress. Previous animal studies have demonstrated the importance of limbic, paralimbic, striatal, and prefrontal structures in ...

PubMed

70
High-field MRI reveals an acute impact on brain function in survivors of the magnitude 8.0 earthquake in China
2009-09-08

Besides the enormous medical and economic consequences, national disasters, such as the Wenchuan 8.0 earthquake, also pose a risk to the mental health of survivors. In this context, a better understanding is needed of how functional brain systems adapt to severe emotional stress. Previous animal studies have demonstrated the importance of limbic, paralimbic, striatal, and prefrontal structures in ...

PubMed Central

71
Functional Brain Correlates of Social and Non-Social Processes in Autism Spectrum Disorders: an ALE Meta-Analysis
2008-11-08

BackgroundFunctional neuroimaging studies of autism spectrum disorders (ASD) have examined social and non-social paradigms, although rarely in the same study. Here, we provide an objective, unbiased survey of functional brain abnormalities in ASD, related to both social and non-social processing.MethodsWe conducted two separate voxel-wise activation likelihood estimation ...

PubMed Central

72
First-episode psychosis is characterized by failure of deactivation but not by hypo- or hyperfrontality.
2011-07-01

BACKGROUND: It is not known whether first-episode psychosis is characterized by the same prefrontal cortex functional imaging abnormalities as chronic schizophrenia.MethodThirty patients with a first episode of non-affective functional psychosis and 28 healthy controls underwent functional magnetic resonance imaging (fMRI) during performance of the n-back working memory task. ...

PubMed

73
Deficits in Functional Connectivity of Hippocampal and Frontal Lobe Circuits after Traumatic Axonal Injury
2011-01-01

ObjectiveTo examine the functional connectivity (fc) of hippocampal and selected frontal lobe circuits among patients with traumatic axonal injury (TAI).DesignEcho-planar and high-resolution T1-weighted images were acquired using 3 Tesla scanners. Regions of interest (ROI) were drawn bilaterally for the hippocampus, anterior cingulate cortex (ACC), and dorsolateral prefrontal cortex (DLPFC), and ...

PubMed Central

74
APOE4 Allele Disrupts Resting State fMRI Connectivity in the Absence of Amyloid Plaques or Decreased CSF A?42
2010-12-15

Identifying high risk populations is an important component of disease prevention strategies. One approach is examining neuroimaging parameters that differ in Alzheimer�s disease (AD), including functional connections known to be disrupted within the �default mode network� (DMN). We have previously shown these same disruptions in ...

PubMed Central

75
Task-Induced Deactivation from Rest Extends beyond the Default Mode Brain Network
2011-07-29

Activity decreases, or deactivations, of midline and parietal cortical brain regions are routinely observed in human functional neuroimaging studies that compare periods of task-based cognitive performance with passive states, such as rest. It is now widely held that such task-induced deactivations index a highly organized �default-mode network� (DMN): ...

PubMed Central

76
Relationships between Beta-Amyloid and Functional Connectivity in Different Components of the Default Mode Network in Aging.
2011-03-07

Although beta-amyloid (A?) deposition is a characteristic feature of Alzheimer's disease (AD), this pathology is commonly found in elderly normal controls (NC). The pattern of A? deposition as detected with Pittsburgh compound-B positron emission tomography (PIB-PET) imaging shows substantial spatial overlap with the default mode ...

PubMed

77
Imaging the default mode network in aging and dementia.
2011-07-23

Although in the last decade brain activation in healthy aging and dementia was mainly studied using task-activation fMRI, there is increasing interest in task-induced decreases in brain activity, termed deactivations. These deactivations occur in the so-called default mode network (DMN). In parallel a growing number of studies focused ...

PubMed

78
Changes in Resting Neural Connectivity during Propofol Sedation
2010-12-02

BackgroundThe default mode network consists of a set of functionally connected brain regions (posterior cingulate, medial prefrontal cortex and bilateral parietal cortex) maximally active in functional imaging studies under �no task� conditions. It has been argued that the posterior cingulate is important in ...

PubMed Central

79
Acupuncture induce the different modulation patterns of the default mode network: an fMRI study
2009-02-01

According to Traditional Chinese Medicine (TCM) theory and certain clinical treatment reports, the sustained effects of acupuncture indeed exist, which may last several minutes or hours. Furthermore, increased attention has fallen on the sustained effects of acupuncture. Recently, it is reported that the sustained acupuncture effects may alter the default ...

NASA Astrophysics Data System (ADS)

80
A comparison of resting-state brain activity in humans and chimpanzees
2007-10-23

In humans, the wakeful resting condition is characterized by a default mode of brain function involving high levels of activity within a functionally connected network of brain regions. This network has recently been implicated in mental self-projection into the past, the future, or another individual's ...

PubMed Central

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81
Task Positive and Default Mode Networks during a Parametric Working Memory Task in Obstructive Sleep Apnea Patients and Healthy Controls
2011-03-01

Introduction:Functional magnetic resonance imaging (fMRI) studies enable the investigation of neural correlates underlying behavioral performance. We investigate the working memory (WM) function of patients with untreated obstructive sleep apnea (OSA) from the view point of task positive and default mode networks (TPN and DMN, ...

PubMed Central

82
Strength of default mode resting-state connectivity relates to white matter integrity in children.
2010-12-09

A default mode network of brain regions is known to demonstrate coordinated activity during the resting state. While the default mode network is well characterized in adults, few investigations have focused upon its development. We scanned 9-13-year-old children with ...

PubMed

83
Are brain networks stable during a 24-hour period?
2011-07-23

Despite the widespread view of the brain as a large complex network, the dynamicity of the brain network over the course of a day has yet to be explored. To investigate whether the spontaneous human brain network maintains long-term stability throughout a day, we evaluated the intra-class correlation coefficient (ICC) of results from ...

PubMed

84
I know the pain you feel-how the human brain's default mode predicts our resonance to another's suffering.
2010-05-05

Introspective and self-referential in nature, the human brain's default mode network (DMN) is presumed to influence our behavior in response to the environment in predictive manner [Raichle ME, Gusnard DA (2005) J Comp Neurol 493:167-176; Bar M (2009) Philos Trans R Soc Lond B Biol Sci 364:1235-1243]. In the current study, we ...

PubMed

85
A neuronal basis for task-negative responses in the human brain.
2010-08-30

Neuroimaging studies have revealed a number of brain regions that show a reduced blood oxygenation level-dependent (BOLD) signal during externally directed tasks compared with a resting baseline. These regions constitute a network whose operation has become known as the default mode. The source of functional magnetic resonance imaging ...

PubMed

86
A Neuronal Basis for Task-Negative Responses in the Human Brain
2011-04-30

Neuroimaging studies have revealed a number of brain regions that show a reduced blood oxygenation level�dependent (BOLD) signal during externally directed tasks compared with a resting baseline. These regions constitute a network whose operation has become known as the default mode. The source of functional magnetic resonance ...

PubMed Central

87
A method for evaluating dynamic functional network connectivity and task-modulation: application to schizophrenia
2010-02-17

ObjectiveIn this paper, we develop a dynamic functional network connectivity (FNC) analysis approach using correlations between windowed time-courses of different brain networks (components) estimated via spatial independent component analysis (sICA). We apply the developed method to fMRI data to evaluate it and to study task-modulation of functional ...

PubMed Central

88
Resting-state functional network correlates of psychotic symptoms in schizophrenia.
2010-01-25

Schizophrenia has been associated with aberrant intrinsic functional organization of the brain but the relationship of such deficits to psychopathology is unclear. In this study, we investigated associations between resting-state networks and individual psychopathology in sixteen patients with paranoid schizophrenia and sixteen matched healthy control participants. We ...

PubMed

89
Slow EEG pattern predicts reduced intrinsic functional connectivity in the default mode network: an inter-subject analysis.
2010-06-09

The last two decades have witnessed great progress in mapping neural networks associated with task-induced brain activation. More recently, identification of resting state networks (RSN) paved the way to investigate spontaneous task-unrelated brain activity. The cardinal features characterising RSN are low-frequency fluctuations of blood oxygenation level ...

PubMed

90
HTML Help for TRACKER3

AMOEBA This is a deterministic downhill simplex search. ... (This is not an easy problem even for humans.) LINAMO (the default mode) This uses the LINEAR ...

NASA Website

91
The development of Human Functional Brain Networks
2010-09-09

Recent advances in MRI technology have enabled precise measurements of correlated activity throughout the brain, leading to the first comprehensive descriptions of functional brain networks in humans. This article reviews the growing literature on the development of functional networks, from infancy through adolescence, as measured by resting state ...

PubMed Central

92
Resting-state functional MRI in depression unmasks increased connectivity between networks via the dorsal nexus.
2010-06-01

To better understand intrinsic brain connections in major depression, we used a neuroimaging technique that measures resting state functional connectivity using functional MRI (fMRI). Three different brain networks--the cognitive control network, default mode network, and affective ...

PubMed

93
Resting-state functional MRI in depression unmasks increased connectivity between networks via the dorsal nexus
2010-06-15

To better understand intrinsic brain connections in major depression, we used a neuroimaging technique that measures resting state functional connectivity using functional MRI (fMRI). Three different brain networks�the cognitive control network, default mode network, and affective ...

PubMed Central

94
Development of the Brain's Default Mode Network from Wakefulness to Slow Wave Sleep.
2011-02-17

Falling asleep is paralleled by a loss of conscious awareness and reduced capacity to process external stimuli. Little is known on sleep-associated changes of spontaneously synchronized anatomical networks as detected by resting-state functional magnetic resonance imaging (rs-fMRI). We employed functional connectivity analysis of rs-fMRI series obtained from 25 healthy ...

PubMed

95
Diffusion Tensor Tractography Reveals Disrupted Topological Efficiency in White Matter Structural Networks in Multiple Sclerosis.
2011-04-01

Little is currently known about the alterations in the topological organization of the white matter (WM) structural networks in patients with multiple sclerosis (MS). In the present study, we used diffusion tensor imaging and deterministic tractography to map the WM structural networks in 39 MS patients and 39 age- and gender-matched healthy controls. ...

PubMed

96
Selective changes of resting-state networks in individuals at risk for Alzheimer's disease
2007-11-20

Alzheimer's disease (AD) is a neurodegenerative disorder that prominently affects cerebral connectivity. Assessing the functional connectivity at rest, recent functional MRI (fMRI) studies reported on the existence of resting-state networks (RSNs). RSNs are characterized by spatially coherent, spontaneous fluctuations in the blood oxygen level-dependent signal and are made up ...

PubMed Central

97
Quasi-periodic Fluctuations in Default Mode Network Electrophysiology.
2011-08-10

The study of human brain electrophysiology has extended beyond traditional frequency ranges identified by the classical EEG rhythms, encompassing both higher and lower frequencies. Changes in high-gamma-band (>70 Hz) power have been identified as markers of local cortical activity. Fluctuations at infra-slow (<0.1 Hz) frequencies have been associated with functionally significant cortical ...

PubMed

98
The self: from philosophy to cognitive neuroscience.
2011-06-01

Neuroscientists have recently begun to explore topics, such as the nature of the self, that were previously considered problems for philosophy rather than for science. This article aims to provide a starting point for interdisciplinary exchange by reviewing three philosophical debates about the nature of the self in light of contemporary work in cognitive neuroscience. Continental rationalist and ...

PubMed

99
Spatial correlation between brain aerobic glycolysis and amyloid-? (A?) deposition
2010-10-12

Amyloid-? (A?) plaque deposition can precede the clinical manifestations of dementia of the Alzheimer type (DAT) by many years and can be associated with changes in brain metabolism. Both the A? plaque deposition and the changes in metabolism appear to be concentrated in the brain's default-mode network. In contrast to prior studies of brain metabolism ...

PubMed Central

100
Mourning and melancholia revisited: correspondences between principles of Freudian metapsychology and empirical findings in neuropsychiatry
2008-07-24

Freud began his career as a neurologist studying the anatomy and physiology of the nervous system, but it was his later work in psychology that would secure his place in history. This paper draws attention to consistencies between physiological processes identified by modern clinical research and psychological processes described by Freud, with a special emphasis on his famous paper on depression ...

PubMed Central

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101
Long-Term Effects of Neurofeedback Treatment in Autism
2008-12-01

Previously we demonstrated significant improvement of executive functions and social behavior in children with autism spectrum disorders (ASD) treated with 40 sessions of EEG neurofeedback in a nonrandomized waiting list control group design. In this paper we extend these findings by reporting the long-term results of neurofeedback treatment in the same group of children with ASD after 12 months. ...

ERIC Educational Resources Information Center

102
Disrupted intrinsic functional connectivity in the vegetative state.
2009-04-01

It is debatable as to whether the spontaneous blood-oxygen-level dependent fluctuations that are observed in the resting brain in turn reflect consciously directed mental activity or, alternatively, constitute an intrinsic property of functional brain organisation persisting in the absence of consciousness. This report shows for the first time, in three patients, that the persistent vegetative ...

PubMed

103
A pilot multivariate parallel ICA study to investigate differential linkage between neural networks and genetic profiles in schizophrenia.
2009-11-26

Understanding genetic influences on both healthy and disordered brain function is a major focus in psychiatric neuroimaging. We utilized task-related imaging findings from an fMRI auditory oddball task known to be robustly associated with abnormal activation in schizophrenia, to investigate genomic factors derived from multiple single nucleotide polymorphisms (SNPs) from genes ...

PubMed

104
Brain activation in complex partial seizures during switching from a the goal-directed task to a resting state: comparison of fMRI maps to the default mode network.
2010-01-01

The default mode network (DMN) has been previously identified as a set of brain regions activated during internally directed cognition. The objective of this study was to investigate patterns of brain activation during switching between a goal-directed task and a rest period obtained from clinical functional magnetic resonance imaging ...

PubMed

105
Resting-state functional connectivity reflects structural connectivity in the default mode network.
2008-04-09

Resting-state functional connectivity magnetic resonance imaging (fcMRI) studies constitute a growing proportion of functional brain imaging publications. This approach detects temporal correlations in spontaneous blood oxygen level-dependent (BOLD) signal oscillations while subjects rest quietly in the scanner. Although distinct resting-state networks related to vision, ...

PubMed

106
Neuronal networks in children with continuous spikes and waves during slow sleep.
2010-08-05

Epileptic encephalopathy with continuous spikes and waves during slow sleep is an age-related disorder characterized by the presence of interictal epileptiform discharges during at least >85% of sleep and cognitive deficits associated with this electroencephalography pattern. The pathophysiological mechanisms of continuous spikes and waves during slow sleep and neuropsychological deficits ...

PubMed

107
Neuronal Networks in Children with Continuous Spikes and Waves during Slow Sleep
2010-09-01

Epileptic encephalopathy with continuous spikes and waves during slow sleep is an age-related disorder characterized by the presence of interictal epileptiform discharges during at least greater than 85% of sleep and cognitive deficits associated with this electroencephalography pattern. The pathophysiological mechanisms of continuous spikes and waves during slow sleep and neuropsychological ...

ERIC Educational Resources Information Center

108
Episodic memory retrieval, parietal cortex, and the default mode network: functional and topographic analyses.
2011-03-23

The default mode network (DMN) is often considered a functionally homogeneous system that is broadly associated with internally directed cognition (e.g., episodic memory, theory of mind, self-evaluation). However, few studies have examined how this network interacts with other networks during ...

PubMed

109
Episodic memory retrieval, parietal cortex, and the Default Mode Network: functional and topographic analyses
2011-03-23

The default mode network (DMN) is often considered a functionally homogeneous system that is broadly associated with internally directed cognition (e.g. episodic memory, theory of mind, self-evaluation). However, few studies have examined how this network interacts with other networks during ...

PubMed Central

110
Default mode of brain function in monkeys.
2011-09-01

Human neuroimaging has revealed a specific network of brain regions-the default-mode network (DMN)-that reduces its activity during goal-directed behavior. So far, evidence for a similar network in monkeys is mainly indirect, since, except for one positron emission tomography study, it is all based on functional ...

PubMed

111
Emergence of resting state networks in the preterm human brain.
2010-11-01

The functions of the resting state networks (RSNs) revealed by functional MRI remain unclear, but it has seemed possible that networks emerge in parallel with the development of related cognitive functions. We tested the alternative hypothesis: that the full repertoire of resting state dynamics emerges during the period of rapid neural growth before the ...

PubMed

112
Emergence of resting state networks in the preterm human brain
2010-11-16

The functions of the resting state networks (RSNs) revealed by functional MRI remain unclear, but it has seemed possible that networks emerge in parallel with the development of related cognitive functions. We tested the alternative hypothesis: that the full repertoire of resting state dynamics emerges during the period of rapid neural growth before the ...

PubMed Central

113
Estimating and adjusting abnormal networks with unknown parameters and topology
2011-03-01

The changes of parameters and topology in a complex network often lead to unexpected accidents in complex systems, such as diseases in neural systems and unexpected current in circuit system, so the methods of adjusting the abnormal network back to its normal conditions are necessary to avoid these problems. However, it is not easy to ...

NASA Astrophysics Data System (ADS)

114
Semantic memory involvement in the default mode network: a functional neuroimaging study using independent component analysis.
2010-10-20

The Default Mode Network (DMN) is a higher order functional neural network that displays activation during passive rest and deactivation during many types of cognitive tasks. Accordingly, the DMN is viewed to represent the neural correlate of internally-generated self-referential cognition. This hypothesis implies ...

PubMed

115
Interrater and Intermethod Reliability of Default Mode Network Selection
2009-07-01

There has been a growing interest in the neuroimaging community regarding resting state data (i.e., passive mental activity) and the subsequent activation of the so-called default mode network (DMN). Although this network was originally characterized by a pattern of deactivation during active cognitive states, more ...

PubMed Central

116
Impact of Load-Related Neural Processes on Feature Binding in Visuospatial Working Memory
2011-08-24

BackgroundThe capacity of visual working memory (WM) is substantially limited and only a fraction of what we see is maintained as a temporary trace. The process of binding visual features has been proposed as an adaptive means of minimising information demands on WM. However the neural mechanisms underlying this process, and its modulation by task and load effects, are not well ...

PubMed Central

117
Functional connectivity comparison of the default mode network in non-depressed Parkinson disease and depressed Parkinson disease
2011-03-01

Examining the spontaneous activity to understand the neural mechanism of brain disorders and establish neuroimaging-based disease-related biomarkers is a focus in recent resting-state functional MRI (fMRI) studies. The present study hypothesized that resting activity in the default mode network (DMN), which was used for characterizing ...

NASA Astrophysics Data System (ADS)

118
Failing to deactivate: the association between brain activity during a working memory task and creativity.
2010-11-25

Working memory (WM) is an essential component for human higher order cognitive activities. Creativity has been essential to the development of human civilization. Previous studies from different fields have suggested creativity and capacity of WM have opposing characteristics possibly in terms of diffuse attention. However, despite a number of functional imaging studies on creativity, how ...

PubMed

119
Default-Mode Function and Task-Induced Deactivation Have Overlapping Brain Substrates in Children
2008-04-01

The regions that comprise the functionally connected resting-state default-mode network (DMN) in adults appear to be the same as those that are characterized by task-induced decreases in blood-oxygen-level-dependent (BOLD) signal. Independent component analysis can be used to produce a picture of the DMN as an individual rests quietly in the scanner. ...

PubMed Central

120
Consistent pivotal role of posterior cingulate cortex in the default mode network revealed by partial correlation analysis
2010-03-01

Resting-state functional MRI (fMRI) studies have suggested the posterior cingulate cortex (PCC) plays a pivotal role in the default mode network (DMN), a set of co-activated brain regions characterizing the resting-state brain. Concerning this finding we propose the following questions in this study: Does PCC consistently play the ...

NASA Astrophysics Data System (ADS)

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121
Alteration of brain default network in subacute phase of injury in concussed individuals: Resting-state fMRI study.
2011-08-01

There are a number of symptoms, both neurological and behavioral, associated with a single episode of r mild traumatic brain injury (mTBI). Neuropsychological testing and conventional neuroimaging techniques are not sufficiently sensitive to detect these changes, which adds to the complexity and difficulty in relating symptoms from mTBI to their underlying structural or functional deficits. With ...

PubMed

122
Visual misperceptions and hallucinations in Parkinson's disease: Dysfunction of attentional control networks?
2011-09-23

Visual misperceptions and hallucinations are a major cause of distress in patients with Parkinson's disease (PD), particularly in the advanced stages of the condition. Recent work has provided a framework for understanding the pathogenesis of these symptoms, implicating impairments from the retina to the integration of external information with preformed internal images. In this article, we ...

PubMed

123
Regional contraction of brain surface area involves three large-scale networks in schizophrenia.
2011-04-15

In schizophrenia, morphological changes in the cerebral cortex have been primarily investigated using volumetric or cortical thickness measurements. In healthy subjects, as the brain size increases, the surface area expands disproportionately when compared to the scaling of cortical thickness. In this structural MRI study, we investigated the changes in brain surface area in schizophrenia by ...

PubMed

124
The influence of rest period instructions on the default mode network.
2010-12-01

The default mode network (DMN) refers to regional brain activity that is greater during rest periods than during attention-demanding tasks; many studies have reported DMN alterations in patient populations. It has also been shown that the DMN is suppressed by scanner background noise (SBN), which is the noise produced by functional ...

PubMed

125
The default mode network and EEG alpha oscillations: An independent component analysis.
2011-05-27

The default mode network (DMN) has been principally investigated using positron emission tomography (PET) and functional magnetic resonance imaging (fMRI) and has received mixed support in electroencephalographic (EEG) studies. In particular, the existing evidence is too inconsistent to allow formulation of specific hypotheses linking ...

PubMed

126
The Influence of Rest Period Instructions on the Default Mode Network
2010-12-01

The default mode network (DMN) refers to regional brain activity that is greater during rest periods than during attention-demanding tasks; many studies have reported DMN alterations in patient populations. It has also been shown that the DMN is suppressed by scanner background noise (SBN), which is the noise produced by functional ...

PubMed Central

127
Modulation of the default mode network is task-dependant in chronic schizophrenia patients.
2010-12-13

The activity of brain regions of the so-called default mode network (DMN) attenuates during the performance of goal-directed tasks. These activity decreases (named task-induced deactivations; TID) are though to reflect the reallocation of cognitive resources from the DMN to areas implicated in the execution of the task. Recently, DMN ...

PubMed

128
Integrated local correlation: a new measure of local coherence in fMRI data.
2009-01-01

This article introduces the measure of integrated local correlation (ILC) for assessing local coherence in the brain using functional magnetic resonance imaging (fMRI) data and characterizes the measure in terms of reproducibility, the effect of physiological noise, and the dependence on image resolution. The coupling of local neuronal processes influences coherence in a voxel's neighborhood. ILC ...

PubMed

129
Impaired Resting-State Functional Integrations within Default Mode Network of Generalized Tonic-Clonic Seizures Epilepsy
2011-02-25

Generalized tonic-clonic seizures (GTCS) are characterized by unresponsiveness and convulsions, which cause complete loss of consciousness. Many recent studies have found that the ictal alterations in brain activity of the GTCS epilepsy patients are focally involved in some brain regions, including thalamus, upper brainstem, medial prefrontal cortex, posterior midbrain regions, and lateral ...

PubMed Central

130
Dopamine Transporters in Striatum Correlate with Deactivation in the Default Mode Network during Visuospatial Attention
2009-06-30

BackgroundDopamine and dopamine transporters (DAT, which regulate extracellular dopamine in the brain) are implicated in the modulation of attention but their specific roles are not well understood. Here we hypothesized that dopamine modulates attention by facilitation of brain deactivation in the default mode network (DMN). Thus, ...

PubMed Central

131
Deficits in default mode network activity preceding error in cocaine dependent individuals.
2011-06-22

BACKGROUND: Cocaine dependence is associated with cognitive deficits and altered task-related cerebral activation in cognitive performance (see Li and Sinha, 2008, for a review). Relatively little is known whether these individuals are also impaired in regional brain activation of the default mode network (DMN). We demonstrated ...

PubMed

132
Brain Activation During Autobiographical Memory Retrieval with Special Reference to Default Mode Network
2011-04-25

Recent neuroimaging studies have suggested that brain regions activated during retrieval of autobiographical memory (ABM) overlap with the default mode network (DMN), which shows greater activation during rest than cognitively demanding tasks and is considered to be involved in self-referential processing. However, detailed overlap and ...

PubMed Central

133
Altered local coherence in the default mode network due to sevoflurane anesthesia.
2010-01-06

Recently we introduced a robust measure, integrated local correlation (ILC), of local connectivity in the brain using fMRI data which reflects the temporal correlation of brain activity in every voxel neighborhood. The current work studies ILC in fMRI data obtained in the absence and presence of sevoflurane anesthesia (0%, 2%, and 1% end-tidal concentration, respectively) administered to healthy ...

PubMed

134
Altered Local Coherence in the Default Mode Network due to Sevoflurane Anesthesia
2010-01-06

Recently we introduced a robust measure, integrated local correlation (ILC), of local connectivity in the brain using fMRI data which reflects the temporal correlation of brain activity in every voxel neighborhood. The current work studies ILC in fMRI data obtained in the absence and presence of sevoflurane anesthesia (0%, 2%, and 1% end-tidal concentration, respectively) administered to healthy ...

PubMed Central

135
Effects of model-based physiological noise correction on default mode network anti-correlations and correlations
2009-05-14

Previous studies have reported that the spontaneous, resting-state time course of the default-mode network is negatively correlated with that of the �task-positive network�, a collection of regions commonly recruited in demanding cognitive tasks. However, all studies of negative correlations between the default-mode and task-positive ...

PubMed Central

136
Temporal dynamics of spontaneous MEG activity in brain networks
2010-03-16

Functional MRI (fMRI) studies have shown that low-frequency (<0.1 Hz) spontaneous fluctuations of the blood oxygenation level dependent (BOLD) signal during restful wakefulness are coherent within distributed large-scale cortical and subcortical networks (resting state networks, RSNs). The neuronal mechanisms underlying RSNs remain poorly understood. ...

PubMed Central

137
BDNF Genotype Modulates Resting Functional Connectivity in Children
2009-11-24

A specific polymorphism of the brain-derived neurotrophic factor (BDNF) gene is associated with alterations in brain anatomy and memory; its relevance to the functional connectivity of brain networks, however, is unclear. Given that altered hippocampal function and structure has been found in adults who carry the methionine (met) allele of the BDNF gene and the molecular ...

PubMed Central

138
Effects of brain amyloid deposition and reduced glucose metabolism on the default mode of brain function in normal aging.
2011-08-01

Brain ?-amyloid (A?) deposition during normal aging is highlighted as an initial pathogenetic event in the development of Alzheimer's disease. Many recent brain imaging studies have focused on areas deactivated during cognitive tasks [the default mode network (DMN), i.e., medial frontal gyrus/anterior cingulate cortex and ...

PubMed

139
Cortical deactivations during gastric fundus distension in health: visceral pain-specific response or attenuation of 'default mode' brain function? A H2 15O-PET study.
2008-10-06

Gastric distension activates a cerebral network including brainstem, thalamus, insula, perigenual anterior cingulate, cerebellum, ventrolateral prefrontal cortex and potentially somatosensory regions. Cortical deactivations during gastric distension have hardly been reported. To describe brain areas of decreased activity during gastric fundus distension compared to baseline, ...

PubMed

140
Consciousness, Plasticity, and Connectomics: The Role of Intersubjectivity in Human Cognition
2011-02-28

Consciousness is typically construed as being explainable purely in terms of either private, raw feels or higher-order, reflective representations. In contrast to this false dichotomy, we propose a new view of consciousness as an interactive, plastic phenomenon open to sociocultural influence. We take up our account of consciousness from the observation of radical cortical neuroplasticity in human ...

PubMed Central

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141
Connectivity pattern changes in default-mode network with deep non-REM and REM sleep.
2011-01-14

Recent studies have compared default-mode network (DMN) connectivity in different arousal levels to investigate the relationship between consciousness and DMN. The comparison between the DMN in rapid eye movement (REM) sleep with that in non-REM (NREM) sleep is useful for revealing the relationship between arousal level and DMN, because the arousal level ...

PubMed

142
Attention-Deficit/Hyperactivity Disorder and Attention Networks
2010-01-16

Research attempting to elucidate the neuropathophysiology of attention-deficit/hyperactivity disorder (ADHD) has not only shed light on the disorder itself, it has simultaneously provided new insights into the mechanisms of normal cognition and attention. This review will highlight and integrate this bidirectional flow of information. Following a brief overview of ADHD clinical phenomenology, ADHD ...

PubMed Central

143
An Administrative Tool for Distributed Security Task ...
2002-01-25

... default mode (see figure 4). There are places for five programs to be scheduled and each of them has a button associated with it, the button name is ...

DTIC Science & Technology

144
The Hippocampus Is Coupled with the Default Network during Memory Retrieval but Not during Memory Encoding
2011-04-11

The brain's default mode network (DMN) is activated during internally-oriented tasks and shows strong coherence in spontaneous rest activity. Despite a surge of recent interest, the functional role of the DMN remains poorly understood. Interestingly, the DMN activates during retrieval of past events but deactivates during encoding of ...

PubMed Central

145
The Default Mode Network In Late-Life Anxious Depression.
2011-07-14

OBJECTIVE:: The aim of this exploratory study is to examine the default-mode network (DMN) functional connectivity pattern in elderly depressed subjects with and without comorbid anxiety. METHODS:: Functional magnetic resonance imaging data were collected for 11 elderly depressed subjects with high comorbid anxiety and eight elderly depressed subjects with low anxiety. We ...

PubMed

146
Resting state activity in patients with disorders of consciousness.

Recent advances in the study of spontaneous brain activity have demonstrated activity patterns that emerge with no task performance or sensory stimulation; these discoveries hold promise for the study of higher-order associative network functionality. Additionally, such advances are argued to be relevant in pathological states, such as disorders of consciousness (DOC), i.e., ...

PubMed

147
Prediction of human errors by maladaptive changes in event-related brain networks
2008-04-22

Humans engaged in monotonous tasks are susceptible to occasional errors that may lead to serious consequences, but little is known about brain activity patterns preceding errors. Using functional MRI and applying independent component analysis followed by deconvolution of hemodynamic responses, we studied error preceding brain activity on a trial-by-trial basis. We found a set of brain regions in ...

PubMed Central

148
Persistent operational synchrony within brain default-mode network and self-processing operations in healthy subjects.
2010-12-18

Based on the theoretical analysis of self-consciousness concepts, we hypothesized that the spatio-temporal pattern of functional connectivity within the default-mode network (DMN) should persist unchanged across a variety of different cognitive tasks or acts, thus being task-unrelated. This supposition is in contrast with current understanding that DMN activated when the ...

PubMed

149
Persistent Operational Synchrony within Brain Default-Mode Network and Self-Processing Operations in Healthy Subjects
2011-03-01

Based on the theoretical analysis of self-consciousness concepts, we hypothesized that the spatio-temporal pattern of functional connectivity within the default-mode network (DMN) should persist unchanged across a variety of different cognitive tasks or acts, thus being task-unrelated. This supposition is in contrast with current understanding that DMN activated when the ...

ERIC Educational Resources Information Center

150
Neuronal correlates of "free will" are associated with regional specialization in the human intrinsic/default network.
2007-12-21

Recently, we proposed a fundamental subdivision of the human cortex into two complementary networks-an "extrinsic" one which deals with the external environment, and an "intrinsic" one which largely overlaps with the "default mode" system, and deals with internally oriented and endogenous mental processes. Here we tested this ...

PubMed

151
Methylphenidate enhances brain activation and deactivation responses to visual attention and working memory tasks in healthy controls.
2010-10-26

Methylphenidate (MPH) is a stimulant drug that amplifies dopamineric and noradrenergic signaling in the brain, which is believed to underlie its cognition enhancing effects. However, the neurobiological effects by which MPH improves cognition are still poorly understood. Here, functional magnetic resonance imaging (fMRI) was used together with working memory (WM) and visual attention (VA) tasks to ...

PubMed

152
Functional connectivity and alterations in baseline brain state in humans.
2009-07-22

This work examines the influence of changes in baseline activity on the intrinsic functional connectivity fMRI (fc-fMRI) in humans. Baseline brain activity was altered by inducing anesthesia (sevoflurane end-tidal concentration 1%) in human volunteers and fc-fMRI maps between the pre-anesthetized and anesthetized conditions were compared across different brain networks. We ...

PubMed

153
Functional connectivity and alterations in baseline brain state in humans
2009-07-22

This work examines the influence of changes in baseline activity on the intrinsic functional connectivity fMRI (fc-fMRI) in humans. Baseline brain activity was altered by inducing anesthesia (sevoflurane end-tidal concentration 1%) in human volunteers and fc-fMRI maps between the pre-anesthetized and anesthetized conditions were compared across different brain networks. We ...

PubMed Central

154
Default-mode network activity distinguishes amnestic type mild cognitive impairment from healthy aging: a combined structural and resting-state functional MRI study.
2008-04-11

Resting-state functional magnetic resonance imaging (MRI), have revealed coactivation in a distributed network that characterizes the default-mode in the human brain. However, details from resting-state imaging in amnestic type mild cognitive impairment (aMCI) is poorly understand. Regional homogeneity, which characterizes low-frequency blood oxygenation level dependent ...

PubMed

155
Brain Connectivity Related to Working Memory Performance
2006-12-20

Several brain areas show signal decreases during many different cognitive tasks in functional imaging studies, including the posterior cingulate cortex (PCC) and a medial frontal region incorporating portions of the medial frontal gyrus and ventral anterior cingulate cortex (MFG/vACC). It has been suggested that these areas are components in a default mode ...

PubMed Central

156
Working Memory Encoding and Maintenance Deficits in Schizophrenia: Neural Evidence for Activation and Deactivation Abnormalities.
2011-09-12

Substantial evidence implicates working memory (WM) as a core deficit in schizophrenia (SCZ), purportedly due to primary deficits in dorsolateral prefrontal cortex functioning. Recent findings suggest that SCZ is also associated with abnormalities in suppression of certain regions during cognitive engagement-namely the default mode ...

PubMed

157
Large-scale directional connections among multi resting-state neural networks in human brain: a functional MRI and Bayesian network modeling study.
2011-03-17

This study examined the large-scale connectivity among multiple resting-state networks (RSNs) in the human brain. Independent component analysis was first applied to the resting-state functional MRI (fMRI) data acquired from 12 healthy young subjects for the separation of RSNs. Four sensory (lateral and medial visual, auditory, and sensory-motor) RSNs and four cognitive ...

PubMed

158
Recent developments of functional magnetic resonance imaging research for drug development in Alzheimer's disease.
2011-07-13

The objective of this review is to evaluate recent advances in functional magnetic resonance imaging (fMRI) research in Alzheimer's disease for the development of therapeutic agents. The basic building block underpinning cognition is a brain network. The measured brain activity serves as an integrator of the various components, from genes to structural integrity, that impact ...

PubMed

159
Network-level structural covariance in the developing brain.
2010-10-04

Intrinsic or resting state functional connectivity MRI and structural covariance MRI have begun to reveal the adult human brain's multiple network architectures. How and when these networks emerge during development remains unclear, but understanding ontogeny could shed light on network function and dysfunction. In this study, we ...

PubMed

160
Network-level structural covariance in the developing brain
2010-10-04

Intrinsic or resting state functional connectivity MRI and structural covariance MRI have begun to reveal the adult human brain's multiple network architectures. How and when these networks emerge during development remains unclear, but understanding ontogeny could shed light on network function and dysfunction. In this study, we ...

PubMed Central

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161
Functionally linked resting-state networks reflect the underlying structural connectivity architecture of the human brain.
2009-10-01

During rest, multiple cortical brain regions are functionally linked forming resting-state networks. This high level of functional connectivity within resting-state networks suggests the existence of direct neuroanatomical connections between these functionally linked brain regions to facilitate the ongoing interregional neuronal communication. White ...

PubMed

162
Cognitive and default-mode resting state networks: do male and female brains "rest" differently?
2010-11-01

Variability in human behavior related to sex is supported by neuroimaging studies showing differences in brain activation patterns during cognitive task performance. An emerging field is examining the human connectome, including networks of brain regions that are not only temporally-correlated during different task conditions, but also networks that show ...

PubMed

163
I KNOW THE PAIN YOU FEEL-HOW THE HUMAN BRAIN'S DEFAULT MODE PREDICTS OUR RESONANCE TO ANOTHER'S SUFFERING

I KNOW THE PAIN YOU FEEL--HOW THE HUMAN BRAIN'S DEFAULT MODE PREDICTS OUR RESONANCE TO ANOTHER representation of their affective states e. g. his or her pain. 19 healthy individuals underwent functional MRI depicting human limbs in painful and non-painful situations. After scanning, participants were asked

E-print Network

164
Volumetric Cerebral Perfusion Imaging in Healthy Adults: Regional Distribution, Laterality, and Repeatability of Pulsed Continuous Arterial Spin Labeling (PCASL)
2010-05-20

The regional distribution, laterality, and reliability of volumetric pulsed continuous arterial spin labeling (PCASL) measurements of cerebral blood flow (CBF) in cortical, subcortical, and cerebellar regions were determined in 10 normal volunteers studied on two occasions separated by 3 to 7 days. Regional CBF, normalized for global perfusion, was highly reliable when measured on separate days. ...

PubMed Central

165
The synchronization of spontaneous BOLD activity predicts extraversion and neuroticism.
2011-08-30

There is an increasing body of evidence pointing to a relationship between personality and brain markers. The purpose of this study was to identify the associations between personality dimensions of extraversion and neuroticism and the local synchronization of spontaneous blood oxygen level-dependent (BOLD) activity assessed by regional homogeneity (ReHo) approach. Our results revealed the ...

PubMed

166
The self in autism: an emerging view from neuroimaging.
2011-06-01

One of the defining characteristics of individuals with autism spectrum disorder (ASD) is difficulty with social interaction and communication with others, or interpersonal interaction. Accordingly, the majority of research efforts to date have focused on understanding the brain mechanisms underlying the deficits in social cognition and language associated with ASD. However, recent empirical and ...

PubMed

167
The self in autism: An emerging view from neuroimaging
2011-06-01

One of the defining characteristics of individuals with autism spectrum disorder (ASD) is difficulty with social interaction and communication with others, or interpersonal interaction. Accordingly, the majority of research efforts to date have focused on understanding the brain mechanisms underlying the deficits in social cognition and language associated with ASD. However, recent empirical and ...

PubMed Central

168
Static and Dynamic Characteristics of Cerebral Blood Flow during the Resting State
2009-07-14

In this study, the static and dynamic characteristics of cerebral blood flow (CBF) in the resting state were investigated using an arterial spin labeling (ASL) perfusion imaging technique. Consistent with previous PET results, static CBF measured by ASL was significantly higher in the posterior cingulate cortex (PCC), thalamus, insula/superior temporal gyrus (STG) and medial prefrontal cortex ...

PubMed Central

169
Reciprocal Imitation: Toward a Neural Basis of Social Interaction.
2011-07-17

Social interaction is a coregulated coupling activity that involves at least 2 autonomous agents. Numerous methodological and technical challenges impede the production of natural social interaction within an Magnetic Resonance Imaging environment under controlled conditions. To overcome the obstacle, we chose a simple format of social interaction, namely "interactive imitation" through a ...

PubMed

170
Mapping and correction of vascular hemodynamic latency in the BOLD signal
2008-07-04

Correlation and causality metrics can be applied to blood-oxygen level dependent (BOLD) signal time series in order to infer neural synchrony and directions of information flow from fMRI data. However, the BOLD signal reflects both the underlying neural activity and the vascular response, the latter of which is governed by local vasomotor physiology. The presence of potential vascular latency ...

PubMed Central

171
Influence of age on the dynamics of fMRI activations during a semantic fluency task.
2011-07-01

PURPOSE: Age-related fMRI changes have not been extensively studied for language, whereas important adaptive mechanisms have been seen in other cognitive fields. This study examined age-related changes in fMRI activation during language tasks and, in particular, their dynamic course. PATIENTS AND METHODS: fMRI was performed on 22 young and 21 old healthy right-handed subjects during a silent ...

PubMed

172
Functional connectivity: a source of variance in the association between cardiorespiratory fitness and cognition?
2010-01-15

Over the next 20 years the number of Americans diagnosed with dementia is expected to more than double (CDC, 2007). It is, therefore, an important public health initiative to understand what factors contribute to the longevity of a healthy mind. Both default mode network (DMN) function and increased aerobic fitness have been associated ...

PubMed

173
Functional Connectivity: A Source of Variance in the Association between Cardiorespiratory Fitness and Cognition?
2010-04-01

Over the next 20 years the number of Americans diagnosed with dementia is expected to more than double (CDC, 2007). It is, therefore, an important public health initiative to understand what factors contribute to the longevity of a healthy mind. Both default mode network (DMN) function and increased aerobic fitness have been associated ...

ERIC Educational Resources Information Center

174
Differential electrophysiological response during rest, self-referential, and non�self-referential tasks in human posteromedial cortex
2011-02-15

The electrophysiological basis for higher brain activity during rest and internally directed cognition within the human default mode network (DMN) remains largely unknown. Here we use intracranial recordings in the human posteromedial cortex (PMC), a core node within the DMN, during conditions of cued rest, autobiographical judgments, ...

PubMed Central

175
Complexity of the Taskless Mind at Different Time-Scales: an Empirically Weighted Approach to Decomposition and Measurement
2011-04-01

The neurodynamical state of an eyes closed at `rest' subject is an area of keen interest in the neuroscience community due to Raichle's field changing concept of the Default Mode Network [1]. The dynamic analysis of neurobiologically derived data commonly involves the computation of distributional measures and time-frequency ...

NASA Astrophysics Data System (ADS)

176
Characteristic changes in brain electrical activity due to chronic hypoxia in patients with obstructive sleep apnea syndrome (OSAS): a combined EEG study using LORETA and omega complexity.
2009-08-27

EEG background activity of patients with obstructive sleep apnea syndrome (OSAS, N = 25) was compared to that of normal controls (N = 14) to reflect alterations of brain electrical activity caused by chronic intermittent hypoxia in OSAS. Global and regional (left vs. right, anterior vs. posterior) measures of spatial complexity (Omega) were used to characterize the degree of spatial synchrony of ...

PubMed

177
Association between Functional Connectivity Hubs and Brain Networks.
2011-01-31

Functional networks are usually accessed with "resting-state" functional magnetic resonance imaging using preselected "seeds" regions. Frequently, however, the selection of the seed locations is arbitrary. Recently, we proposed local functional connectivity density mapping (FCDM), an ultrafast data-driven to locate highly connected brain regions (functional hubs). Here, we ...

PubMed

178
Spontaneous Brain Activity in the Default Mode Network Is Sensitive to Different Resting-State Conditions with Limited Cognitive Load
2009-05-29

BackgroundRecent functional MRI (fMRI) studies have demonstrated that there is an intrinsically organized default mode network (DMN) in the resting brain, primarily made up of the posterior cingulate cortex (PCC) and the medial prefrontal cortex (MPFC). Several previous studies have found that the DMN is minimally disturbed during ...

PubMed Central

179
Plasticity of Brain Networks in a Randomized Intervention Trial of Exercise Training in Older Adults
2010-08-26

Research has shown the human brain is organized into separable functional networks during rest and varied states of cognition, and that aging is associated with specific network dysfunctions. The present study used functional magnetic resonance imaging (fMRI) to examine low-frequency (0.008?

PubMed Central

180
Intrinsic Brain Connectivity in Fibromyalgia is Associated with Chronic Pain Intensity
2010-08-01

OBJECTIVEFibromyalgia (FM) is considered to be the prototypical central chronic pain syndrome and is associated with widespread pain that fluctuates spontaneously. Multiple studies have demonstrated altered brain activity in these patients. Our objective was to investigate the degree of connectivity between multiple brain networks in FM, as well as how activity in these ...

PubMed Central

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181
Basal functional connectivity within the anterior temporal network is associated with performance on declarative memory tasks.
2011-06-21

Spontaneous fluctuations in the blood oxygenation level-dependent (BOLD) signal, as measured by functional magnetic resonance imaging (fMRI) at rest, exhibit a temporally coherent activity thought to reflect functionally relevant networks. Antero-mesial temporal structures are the site of early pathological changes in Alzheimer's disease and have been shown to be critical for ...

PubMed

182
Selective aberrant functional connectivity of resting state networks in social anxiety disorder.
2010-05-11

Several functional MRI (fMRI) activation studies have highlighted specific differences in brain response in social anxiety disorder (SAD) patients. Little is known, so far, about the changes in the functional architecture of resting state networks (RSNs) in SAD during resting state. We investigated statistical differences in RSNs on 20 SAD and 20 controls using independent ...

PubMed

183
Combination of DTI and fMRI reveals the white matter changes correlating with the decline of default-mode network activity in Alzheimer's disease
2009-02-01

Recently, evidences from fMRI studies have shown that there was decreased activity among the default-mode network in Alzheimer's disease (AD), and DTI researches also demonstrated that demyelinations exist in white matter of AD patients. Therefore, combining these two MRI methods may help to reveal the relationship between white matter damages and alterations of the resting ...

NASA Astrophysics Data System (ADS)

184
Brain Connectivity in Pathological and Pharmacological Coma
2010-12-20

Recent studies in patients with disorders of consciousness (DOC) tend to support the view that awareness is not related to activity in a single brain region but to thalamo-cortical connectivity in the frontoparietal network. Functional neuroimaging studies have shown preserved albeit disconnected low-level cortical activation in response to external stimulation in patients in ...

PubMed Central

185
The impact of global signal regression on resting state correlations: are anti-correlated networks introduced?
2008-10-11

Low-frequency fluctuations in fMRI signal have been used to map several consistent resting state networks in the brain. Using the posterior cingulate cortex as a seed region, functional connectivity analyses have found not only positive correlations in the default mode network but negative correlations in another ...

PubMed

186
The impact of global signal regression on resting state correlations: Are anti-correlated networks introduced?
2008-10-11

Low-frequency fluctuations in fMRI signal have been used to map several consistent resting state networks in the brain. Using the posterior cingulate cortex as a seed region, functional connectivity analyses have found not only positive correlations in the default mode network but negative correlations in another ...

PubMed Central

187
Pattern Classification of Working Memory Networks Reveals Differential Effects of Methylphenidate, Atomoxetine, and Placebo in Healthy Volunteers
2011-05-23

Stimulant and non-stimulant drugs can reduce symptoms of attention deficit/hyperactivity disorder (ADHD). The stimulant drug methylphenidate (MPH) and the non-stimulant drug atomoxetine (ATX) are both widely used for ADHD treatment, but their differential effects on human brain function remain unclear. We combined event-related fMRI with multivariate pattern recognition to characterize the effects ...

PubMed Central

188
Robustness of intrinsic connectivity networks in the human brain to the presence of acoustic scanner noise.
2011-01-19

Evoked responses in functional magnetic resonance imaging (fMRI) are affected by the presence of acoustic scanner noise (ASN). Particularly, stimulus-related activation of the auditory system and deactivation of the default mode network have repeatedly been shown to diminish. In contrast, little is known about the influence of ASN on ...

PubMed

189
Evaluating the effective connectivity of resting state networks using conditional Granger causality.
2009-11-25

The human brain has been documented to be spatially organized in a finite set of specific coherent patterns, namely resting state networks (RSNs). The interactions among RSNs, being potentially dynamic and directional, may not be adequately captured by simple correlation or anticorrelation. In order to evaluate the possible effective connectivity within those RSNs, we applied ...

PubMed

190
Detecting overlapped functional clusters in resting state fMRI with Connected Iterative Scan: a graph theory based clustering algorithm.
2011-05-05

The brain is a complex neural network with interleaving functional connectivity among anatomical regions. However, current functional parcellation algorithms usually emphasize independence or orthogonality between the spatial components, with the interleaving nature underrepresented. This study investigates a method, Connected Iterative Scan (CIS), for identifying functionally ...

PubMed

191
Abstract- The increasing deployment of Wireless Networks has experienced also an exponential increase in wireless faults

to evaluate the wireless network normal and abnormal behaviors and create dynamic normal and abnormal contours metrics, referred to as wireless abnormality distance (WAD), to quantify the network behavior. Wireless wireless abnormality distance KWAD with respect to a ...

E-print Network

192
Using spatial multiple regression to identify intrinsic connectivity networks involved in working memory performance.
2011-07-14

Many researchers have noted that the functional architecture of the human brain is relatively invariant during task performance and the resting state. Indeed, intrinsic connectivity networks (ICNs) revealed by resting-state functional connectivity analyses are spatially similar to regions activated during cognitive tasks. This suggests that patterns of task-related activation ...

PubMed

193
Resting-state networks in awake five- to eight-year old children.
2011-04-25

During the first 6-7 years of life children undergo a period of major neurocognitive development. Higher-order cognitive functions such as executive control of attention, encoding and retrieving of stored information and goal-directed behavior are present but less developed compared to older individuals. There is only very limited information from functional magnetic resonance imaging (fMRI) ...

PubMed

194
Reading networks at rest.
2010-02-05

Resting-state functional connectivity (RSFC) approaches offer a novel tool to delineate distinct functional networks in the brain. In the present functional magnetic resonance imaging (fMRI) study, we elucidated patterns of RSFC associated with 6 regions of interest selected primarily from a meta-analysis on word reading (Bolger DJ, Perfetti CA, Schneider W. 2005. ...

PubMed

195
Functional Connectivity of the Posteromedial Cortex
2010-09-30

As different areas within the PMC have different connectivity patterns with various cortical and subcortical regions, we hypothesized that distinct functional modules may be present within the PMC. Because the PMC appears to be the most active region during resting state, it has been postulated to play a fundamental role in the control of baseline brain functioning within the ...

PubMed Central

196
Electro-acupuncture at different acupoints modulating the relative specific brain functional network
2010-11-01

Objective: The specific brain effects of acupoint are important scientific concern in acupuncture. However, previous acupuncture fMRI studies focused on acupoints in muscle layer on the limb. Therefore, researches on acupoints within connective tissue at trunk are warranted. Material and Methods: Brain effects of acupuncture on abdomen at acupoints Guanyuan (CV4) and Zhongwan (CV12) were tested ...

NASA Astrophysics Data System (ADS)

197
Dysfunctions of cerebral networks precede recognition memory deficits in early Parkinson's disease.
2011-04-30

We aimed to investigate changes in the verbal recognition memory network in patients with early Parkinson's disease (PD) without overt recognition memory alteration. Verbal recognition memory was assessed in 24 PD patients in early stages of the disease and a control group of 24 healthy subjects during fMRI data acquisition. Participants were presented with a list of 35 words ...

PubMed

198
Disruption of Functional Connectivity of the Default-Mode Network in Alcoholism.
2011-03-01

The default mode network (DMN) comprises brain structures maximally active at rest. Disturbance of network nodes or their connections occurs with some neuropsychiatric conditions and may underlie associated dysfunction. DMN connectivity has not been examined in alcoholism, which is marked by compromised DMN nodes ...

PubMed

199
Development of functional and structural connectivity within the default mode network in young children
2010-04-10

Functional and structural maturation of networks comprised of discrete regions is an important aspect of brain development. The default-mode network (DMN) is a prominent network which includes the posterior cingulate cortex (PCC), medial prefrontal cortex (mPFC), medial temporal lobes (MTL), and angular gyrus (AG). Despite increasing ...

PubMed Central

200
Altered self-referential network in resting-state amnestic type mild cognitive impairment.
2011-02-15

INTRODUCTION: Impaired capacity for self-reference has been observed in amnestic mild cognitive impairment (aMCI) subjects who are thought to be the likely to develop into clinical Alzheimer's disease (AD). The altered pattern of self-referencing network (SRN) is not yet well understood in aMCI subjects particularly in resting state, and little is known about the relationship ...

PubMed

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