Quantifying the Variability in Resting-State Networks

Recent precision functional mapping of individual human brains has shown that individual brain organization is qualitatively different from group average estimates and that individuals exhibit distinct brain network topologies. How this variability affects the connectivity within individual resting-state networks remains an open question. This is particularly important since certain resting-state networks such as the default mode network (DMN) and the fronto-parietal network (FPN) play an important role in the early detection of neurophysiological diseases like Alzheimer’s, Parkinson’s, and attention deficit hyperactivity disorder. Using different types of similarity measures including conditional mutual information, we show here that the backbone of the functional connectivity and the direct connectivity within both the DMN and the FPN does not vary significantly between healthy individuals for the AAL brain atlas. Weaker connections do vary however, having a particularly pronounced effect on the cross-connections between DMN and FPN. Our findings suggest that the link topology of single resting-state networks is quite robust if a fixed brain atlas is used and the recordings are sufficiently long—even if the whole brain network topology between different individuals is variable.

Download Full-text

The frontoparietal network: function, electrophysiology, and importance of individual precision mapping

Dialogues in Clinical Neuroscience ◽

10.31887/dcns.2018.20.2/smarek ◽

2018 ◽

Vol 20 (2) ◽

pp. 133-140 ◽

Cited By ~ 60

Keyword(s):

Resting State ◽

Resting State Networks ◽

Individual Subject ◽

Network Function ◽

Hyperactivity Disorder ◽

Frontoparietal Network ◽

Functional Brain Networks ◽

Network Coordination ◽

Functional Topography ◽

Human Brains

The frontoparietal network is critical for our ability to coordinate behavior in a rapid, accurate, and flexible goal-driven manner. In this review, we outline support for the framing of the frontoparietal network as a distinct control network, in part functioning to flexibly interact with and alter other functional brain networks. This network coordination likely occurs in a 4 Hz to13 Hz θ/α rhythm, both during resting state and task state. Precision mapping of individual human brains has revealed that the functional topography of the frontoparietal network is variable between individuals, underscoring the notion that group-average studies of the frontoparietal network may be obscuring important typical and atypical features. Many forms of psychopathology implicate the frontoparietal network, such as schizophrenia and attention-deficit/hyperactivity disorder. Given the interindividual variability in frontoparietal network organization, clinical studies will likely benefit greatly from acquiring more individual subject data to accurately characterize resting-state networks compromised in psychopathology

Download Full-text

Mapping Sensorimotor Cortex With Slow Cortical Potential Resting-State Networks While Awake and Under Anesthesia

Neurosurgery ◽

10.1227/neu.0b013e318258e5d1 ◽

2012 ◽

Vol 71 (2) ◽

pp. 305-316 ◽

Cited By ~ 24

Author(s):

Jonathan D. Breshears ◽

Charles M. Gaona ◽

Jarod L. Roland ◽

Mohit Sharma ◽

David T. Bundy ◽

...

Keyword(s):

Brain Mapping ◽

Sensorimotor Cortex ◽

Resting State ◽

Intractable Epilepsy ◽

Cortical Potential ◽

Data Driven ◽

Resting State Networks ◽

Seed Selection ◽

Brain Organization ◽

Slow Cortical Potential

Abstract BACKGROUND: The emerging insight into resting-state cortical networks has been important in our understanding of the fundamental architecture of brain organization. These networks, which were originally identified with functional magnetic resonance imaging, are also seen in the correlation topography of the infraslow rhythms of local field potentials. Because of the fundamental nature of these networks and their independence from task-related activations, we posit that, in addition to their neuroscientific relevance, these slow cortical potential networks could play an important role in clinical brain mapping. OBJECTIVE: To assess whether these networks would be useful in identifying eloquent cortex such as sensorimotor cortex in patients both awake and under anesthesia. METHODS: This study included 9 subjects undergoing surgical treatment for intractable epilepsy. Slow cortical potentials were recorded from the cortical surface in patients while awake and under propofol anesthesia. To test brain-mapping utility, slow cortical potential networks were identified with data-driven (seed-independent) and anatomy-driven (seed-based) approaches. With electrocortical stimulation used as the gold standard for comparison, the sensitivity and specificity of these networks for identifying sensorimotor cortex were calculated. RESULTS: Networks identified with a data-driven approach in patients under anesthesia and awake were 90% and 93% sensitive and 58% and 55% specific for sensorimotor cortex, respectively. Networks identified with systematic seed selection in patients under anesthesia and awake were 78% and 83% sensitive and 67% and 60% specific, respectively. CONCLUSION: Resting-state networks may be useful for tailoring stimulation mapping and could provide a means of identifying eloquent regions in patients while under anesthesia.

Download Full-text

Childhood Trauma Associated With Abnormal Resting-State Brain Network Connectivity in First-Episode Schizophrenia Patients

10.21203/rs.3.rs-73545/v1 ◽

2020 ◽

Author(s):

Xiangyun Long ◽

Jiaxin Wu ◽

Fei Liu ◽

Ansi Qi ◽

Nan Huang ◽

...

Keyword(s):

Childhood Trauma ◽

Resting State ◽

Network Connectivity ◽

Brain Network ◽

Traumatic Experiences ◽

First Episode ◽

Resting State Networks ◽

Attention Network ◽

Brain Network Connectivity ◽

First Episode Schizophrenia

Abstract Childhood trauma is a central risk factor for schizophrenia. We explored the correlation between early traumatic experiences and the functional connectivity of resting-state networks. This fMRI study included 28 first-episode schizophrenia patients and 27 healthy controls. In first-episode schizophrenia patients, higher levels of childhood trauma associated with abnormal connections of resting-state networks, and these anomalies distributed among task-positive networks (i.e., ventral attention network, dorsal-ventral attention network and frontal-parietal network), and sensory networks (i.e., visual network and auditory network). These findings mentioned that childhood traumatic experiences may impact resting-state network connectivity in adulthood, mainly involving systems related to attention and execution control.

Download Full-text

Increased soluble amyloid-beta causes early aberrant brain network hypersynchronisation in a mature-onset mouse model of amyloidosis

Acta Neuropathologica Communications ◽

10.1186/s40478-019-0810-7 ◽

2019 ◽

Vol 7 (1) ◽

Author(s):

Inès R. H. Ben-Nejma ◽

Aneta J. Keliris ◽

Jasmijn Daans ◽

Peter Ponsaerts ◽

Marleen Verhoye ◽

...

Keyword(s):

Mouse Model ◽

Postnatal Development ◽

Amyloid Beta ◽

Resting State ◽

Inflammatory Responses ◽

Ex Vivo ◽

Fold Increase ◽

Brain Network ◽

Resting State Networks ◽

The Impact

AbstractAlzheimer’s disease (AD) is the most common form of dementia in the elderly. According to the amyloid hypothesis, the accumulation and deposition of amyloid-beta (Aβ) peptides play a key role in AD. Soluble Aβ (sAβ) oligomers were shown to be involved in pathological hypersynchronisation of brain resting-state networks in different transgenic developmental-onset mouse models of amyloidosis. However, the impact of protein overexpression during brain postnatal development may cause additional phenotypes unrelated to AD. To address this concern, we investigated sAβ effects on functional resting-state networks in transgenic mature-onset amyloidosis Tet-Off APP (TG) mice. TG mice and control littermates were raised on doxycycline (DOX) diet from 3d up to 3 m of age to suppress transgenic Aβ production. Thereafter, longitudinal resting-state functional MRI was performed on a 9.4 T MR-system starting from week 0 (3 m old mice) up to 28w post DOX treatment. Ex-vivo immunohistochemistry and ELISA analysis was performed to assess the development of amyloid pathology. Functional Connectivity (FC) analysis demonstrated early abnormal hypersynchronisation in the TG mice compared to the controls at 8w post DOX treatment, particularly across regions of the default mode-like network, known to be affected in AD. Ex-vivo analyses performed at this time point confirmed a 20-fold increase in total sAβ levels preceding the apparition of Aβ plaques and inflammatory responses in the TG mice compared to the controls. On the contrary at week 28, TG mice showed an overall hypoconnectivity, coinciding with a widespread deposition of Aβ plaques in the brain. By preventing developmental influence of APP and/or sAβ during brain postnatal development, we demonstrated FC abnormalities potentially driven by sAβ neurotoxicity on resting-state neuronal networks in mature-induced TG mice. Thus, the Tet-Off APP mouse model could be a powerful tool while used as a mature-onset model to shed light into amyloidosis mechanisms in AD.

Download Full-text

Brain Organization into Resting State Networks Emerges at Criticality on a Model of the Human Connectome

Physical Review Letters ◽

10.1103/physrevlett.110.178101 ◽

2013 ◽

Vol 110 (17) ◽

Cited By ~ 231

Author(s):

Ariel Haimovici ◽

Enzo Tagliazucchi ◽

Pablo Balenzuela ◽

Dante R. Chialvo

Keyword(s):

Resting State ◽

Resting State Networks ◽

Brain Organization

Download Full-text

Increased soluble amyloid-beta causes early aberrant brain network hypersynchronisation in a mature-onset mouse model of amyloidosis

10.1101/723981 ◽

2019 ◽

Author(s):

Inès R.H. Ben-Nejma ◽

Aneta J. Keliris ◽

Jasmijn Daans ◽

Peter Ponsaerts ◽

Marleen Verhoye ◽

...

Keyword(s):

Mouse Model ◽

Postnatal Development ◽

Amyloid Beta ◽

Resting State ◽

Ex Vivo ◽

Fold Increase ◽

Brain Network ◽

Resting State Networks ◽

The Impact

ABSTRACTBackgroundAlzheimer’s disease (AD) is the most common form of dementia in the elderly population. Currently, no effective cure is available for AD. According to the amyloid hypothesis, the accumulation and deposition of the amyloid-beta (Aβ) peptides plays a key role in AD pathology. Soluble Aβ (sAβ) oligomers were shown to be synaptotoxic and involved in pathological hypersynchronisation of brain resting-state networks in different transgenic developmental-onset mouse models of amyloidosis. However, the impact of protein overexpression during brain postnatal development may cause additional phenotypes unrelated to AD. To address this concern, we investigated sAβ effects on functional resting-state networks in transgenic mature-onset amyloidosis Tet-Off APP (TG) mice.MethodsTG mice and control littermates were raised on doxycycline (DOX) diet from 3d up to 3m of age to suppress transgenic Aβ production. Thereafter, longitudinal resting-state functional MRI was performed on a 9.4T MR-system starting from week 0 (3m old mice) up to 28w post DOX treatment. Ex vivo immunohistochemistry and ELISA analysis (additional mice cohort) was performed to address the development of amyloid pathology.ResultsFunctional Connectivity (FC) analysis demonstrated early abnormal hypersynchronisation in the TG mice compared to the controls at 8w post DOX treatment. This effect was observed particularly across regions of the default mode-like network, known to be affected in AD. Ex vivo analyses performed at this time point confirmed a 20-fold increase in total sAβ levels and the absence of Aβ plaques in the TG mice compared to the controls. On the contrary at week 28, TG mice showed an overall hypoconnectivity, coinciding with a widespread deposition of Aβ plaques in the brain.ConclusionsBy preventing developmental influence of APP and/or sAβ during brain postnatal development, we demonstrated FC abnormalities driven by sAβ synaptotoxicity on resting state neuronal networks in mature-induced TG mice. Thus, the Tet-Off APP mouse model could be a powerful tool while used as a mature-onset model to shed light into amyloidosis mechanisms in AD. Therefore, this inducible APP expression model used in combination with early non-invasive in vivo rsfMRI readout for sAβ synaptotoxicity sets the stage for future Aβ targeting preventative treatment studies.

Download Full-text

Atlas55+: Brain Functional Atlas of Resting-state Networks for Late Adulthood

10.1101/2020.07.13.200824 ◽

2020 ◽

Author(s):

Gaelle E. Doucet ◽

Loic Labache ◽

Paul M. Thompson ◽

Marc Joliot ◽

Sophia Frangou ◽

...

Keyword(s):

Older Adult ◽

Resting State ◽

Brain Atlas ◽

Resting State Networks ◽

Late Adulthood ◽

Total N ◽

Healthy Older Adults ◽

Age Appropriate ◽

Older Populations ◽

Brain Atlases

AbstractCurrently, several human brain functional atlases are used to define the spatial constituents of the resting-state networks (RSNs). However, the only brain atlases available are derived from samples of young adults. As brain networks are continuously reconfigured throughout life, the lack of brain atlases derived from older populations may influence RSN results in late adulthood. To address this gap, the aim of the study was to construct a reliable brain atlas derived only from older participants. We leveraged resting-state functional MRI data from three cohorts of healthy older adults (total N=563; age=55-95years) and a younger-adult cohort (N=128; age=18-35 years). We identified the major RSNs and their subdivisions across all older-adult cohorts. We demonstrated high spatial reproducibility of these RSNs with an average spatial overlap of 67%. Importantly, the RSNs derived from the older-adult cohorts were spatially different from those derived from the younger-adult cohort (p=2.3×10−3). Lastly, we constructed a novel brain atlas, called Atlas55+, which includes the consensus of the major RSNs and their subdivisions across the older-adult cohorts. Thus, Atlas55+ provides a reliable age-appropriate template for RSNs in late adulthood and is publicly available. Our results confirm the need for age-appropriate functional atlases for studies investigating aging-related brain mechanisms.

Download Full-text

The dynamic modular fingerprints of the human brain at rest

10.1101/2020.05.30.125385 ◽

2020 ◽

Author(s):

Aya Kabbara ◽

Veronique Paban ◽

Mahmoud Hassan

Keyword(s):

Human Brain ◽

Resting State ◽

Brain Networks ◽

Brain Network ◽

Strongly Correlated ◽

Resting State Networks ◽

Modular Network ◽

Track Dynamics ◽

Network Pattern ◽

Over Time

AbstractThe human brain is a dynamic modular network that can be decomposed into a set of modules and its activity changes permanently over time. At rest, several brain networks, known as Resting-State Networks (RSNs), emerge and cross-communicate even at sub-second temporal scale. Here, we seek to decipher the fast reshaping in spontaneous brain modularity and its relationship to RSNs. We use Electro/Magneto-Encephalography (EEG/MEG) to track dynamics of modular brain networks, in three independent datasets (N= 568) of healthy subjects at rest. We show the presence of striking spatiotemporal network pattern consistent over participants. We also show that some RSNs, such as default mode network and temporal network, are not necessary ‘unified units’ but rather can be divided into multiple sub-networks over time. Using the resting state questionnaire, our results revealed also that brain network dynamics are strongly correlated to mental imagery at rest. These findings add new perspectives to brain dynamic analysis and highlight the importance of tracking fast reconfiguration of electrophysiological networks at rest.

Download Full-text

Pig Brains Have Homologous Resting-State Networks with Human Brains

Brain Connectivity ◽

10.1089/brain.2019.0673 ◽

2019 ◽

Vol 9 (7) ◽

pp. 566-579 ◽

Cited By ~ 4

Author(s):

Gregory Simchick ◽

Alice Shen ◽

Brandon Campbell ◽

Hea Jin Park ◽

Franklin D. West ◽

...

Keyword(s):

Resting State ◽

Resting State Networks ◽

Human Brains

Download Full-text

Association of Network Connectivity via Resting State Functional MRI with Consciousness, Mortality, and Outcomes in Neonatal Acute Brain Injury

10.1101/2021.10.18.21265147 ◽

2021 ◽

Author(s):

Varina L. Boerwinkle ◽

Bethany Sussman ◽

Iliana Manjon ◽

Lucia Mirea ◽

Saher Suleman ◽

...

Keyword(s):

Brain Injury ◽

Developmental Delay ◽

Functional Mri ◽

Resting State ◽

Brain Network ◽

Acute Brain Injury ◽

Discharge Condition ◽

Resting State Networks ◽

Network Function ◽

Neurological Exam

Background An accurate and comprehensive test of integrated brain network function is needed for neonates during the acute brain injury period to inform on morbidity. This retrospective cohort study aimed to assess whether integrated brain network function by resting state functional MRI, acquired during the acute period in neonates with brain injury, is associated with acute exam, neonatal mortality, and 5-month outcomes. Methods This study included 40 consecutive neonates with resting state functional MRI acquired 1-22 days after suspected brain insult from March 2018 to July 2019 at Phoenix Childrens Hospital. Acute period exam and test results were assigned ordinal scores based on severity as documented by respective treating specialists. Analyses (Fisher exact, Wilcoxon-rank sum test, ordinal/multinomial logistic regression) examined association of resting state networks with demographics, presentation, neurological exam, electroencephalogram, anatomical MRI, magnetic resonance spectroscopy, passive task functional MRI, and outcomes of discharge condition, outpatient development, motor tone, seizure, and mortality. Results Subjects had a mean (standard deviation) gestational age of 37.8 (2.6) weeks, a majority were male (63%), with diagnosis of hypoxic ischemic encephalopathy (68%). Other findings at birth included mild distress (48%), moderately abnormal neurological exam (33%), and consciousness characterized as awake but irritable (40%). Significant associations after multiple testing corrections were detected for resting state networks: basal ganglia with outpatient developmental delay (odds ratio [OR], 14.5; 99.4% confidence interval [CI], 2.00-105; P<.001) and motor tone/weakness (OR, 9.98; 99.4% CI, 1.72-57.9; P<.001); language/frontal-parietal network with discharge condition (OR, 5.13; 99.4% CI, 1.22-21.5; P=.002) and outpatient developmental delay (OR, 4.77; 99.4% CI, 1.21-18.7; P=.002); default mode network with discharge condition (OR, 3.72; 99.4% CI, 1.01-13.78; P=.006) and neurological exam (P=.002 (FE); OR, 11.8; 99.4% CI, 0.73-191; P=.01 (OLR)); seizure onset zone with motor tone/weakness (OR, 3.31; 99.4% CI, 1.08-10.1; P=.003). Resting state networks were not detected in only three neonates, who died prior to discharge. Conclusions This study provides level 3 evidence (OCEBM Levels of Evidence Working Group) that the degree of abnormality of resting state networks in neonatal acute brain injury is associated with acute exam and outcomes. Total lack of brain network detection was only found in patients who did not survive.

Download Full-text