scholarly journals Multimodal Study of Resting-State Functional Connectivity Networks using EEG electrodes position as seed

2017 ◽  
Author(s):  
Gonzalo M. Rojas ◽  
Carolina Alvarez ◽  
Carlos Montoya ◽  
María de la Iglesia-Vayá ◽  
Jaime Cisternas ◽  
...  
Keyword(s):  
Functional Connectivity ◽  
Spatial Resolution ◽  
Temporal Resolution ◽  
Neural Activity ◽  
Resting State ◽  
Blood Oxygenation ◽  
High Temporal Resolution ◽  
Resting State Functional Connectivity ◽  
Diagnosis Method ◽  
Eeg Connectivity

AbstractElectroencephalography (EEG) is the standard diagnosis method for a wide variety of diseases such as epilepsy, sleep disorders, encephalopathies, and coma, among others. Resting-state functional magnetic resonance (rs-fMRI) is currently a technique used in research in both healthy individuals as well as patients. EEG and fMRI are procedures used to obtain direct and indirect measurements of brain neural activity: EEG measures the electrical activity of the brain using electrodes placed on the scalp, and fMRI detects the changes in blood oxygenation that occur in response to neural activity. EEG has a high temporal resolution and low spatial resolution, while fMRI has high spatial resolution and low temporal resolution. Thus, the combination of EEG with rs-fMRI using different methods could be very useful for research and clinical applications. In this article, we describe and show the results of a new methodology for processing rs-fMRI using seeds positioned according to the 10-10 EEG standard. We analyze the functional connectivity and adjacency matrices obtained using 65 seeds based on 10-10 EEG scheme and 21 seeds based on 10-20 EEG. Connectivity networks are created using each 10-20 EEG seeds and are analyzed by comparisons to the seven networks that have been found in recent studies. The proposed method captures high correlation between contralateral seeds, ipsilateral and contralateral occipital seeds, and some in the frontal lobe.

scholarly journals Resting state functional connectivity in the human spinal cord

eLife ◽  
2014 ◽  
Vol 3 ◽  
Author(s):  
Robert L Barry ◽  
Seth A Smith ◽  
Adrienne N Dula ◽  
John C Gore
Keyword(s):  
Spinal Cord ◽  
Functional Connectivity ◽  
Resting State ◽  
Low Frequency ◽  
Blood Oxygenation ◽  
Resting State Functional Connectivity ◽  
Human Spinal Cord ◽  
Oxygenation Level ◽  
Left And Right ◽  
The Brain

Functional magnetic resonance imaging using blood oxygenation level dependent (BOLD) contrast is well established as one of the most powerful methods for mapping human brain function. Numerous studies have measured how low-frequency BOLD signal fluctuations from the brain are correlated between voxels in a resting state, and have exploited these signals to infer functional connectivity within specific neural circuits. However, to date there have been no previous substantiated reports of resting state correlations in the spinal cord. In a cohort of healthy volunteers, we observed robust functional connectivity between left and right ventral (motor) horns, and between left and right dorsal (sensory) horns. Our results demonstrate that low-frequency BOLD fluctuations are inherent in the spinal cord as well as the brain, and by analogy to cortical circuits, we hypothesize that these correlations may offer insight into the execution and maintenance of sensory and motor functions both locally and within the cerebrum.

scholarly journals Differential Resting State Connectivity Responses to Glycemic State in Type 1 Diabetes

2019 ◽  
Vol 105 (1) ◽  
pp. 1-13 ◽  
Author(s):  
Lisa Parikh ◽  
Dongju Seo ◽  
Cheryl Lacadie ◽  
Renata Belfort-Deaguiar ◽  
Derek Groskreutz ◽  
...  
Keyword(s):  
Type 1 Diabetes ◽  
Functional Connectivity ◽  
Resting State ◽  
Academic Medical Center ◽  
Blood Oxygenation ◽  
Angular Gyrus ◽  
Resting State Functional Connectivity ◽  
The Impact ◽  
Resting State Connectivity

Abstract Context Individuals with type 1 diabetes mellitus (T1DM) have alterations in brain activity that have been postulated to contribute to the adverse neurocognitive consequences of T1DM; however, the impact of T1DM and hypoglycemic unawareness on the brain’s resting state activity remains unclear. Objective To determine whether individuals with T1DM and hypoglycemia unawareness (T1DM-Unaware) had changes in the brain resting state functional connectivity compared to healthy controls (HC) and those with T1DM and hypoglycemia awareness (T1DM-Aware). Design Observational study. Setting Academic medical center. Participants 27 individuals with T1DM and 12 HC volunteers participated in the study. Intervention All participants underwent blood oxygenation level dependent (BOLD) resting state functional magnetic brain imaging during a 2-step hyperinsulinemic euglycemic (90 mg/dL)–hypoglycemic (60 mg/dL) clamp. Outcome Changes in resting state functional connectivity. Results Using 2 separate methods of functional connectivity analysis, we identified distinct differences in the resting state brain responses to mild hypoglycemia between HC, T1DM-Aware, and T1DM-Unaware participants, particularly in the angular gyrus, an integral component of the default mode network (DMN). Furthermore, changes in angular gyrus connectivity also correlated with greater symptoms of hypoglycemia (r = 0.461, P = 0.003) as well as higher scores of perceived stress (r = 0.531, P = 0.016). Conclusion These findings provide evidence that individuals with T1DM have changes in the brain’s resting state connectivity patterns, which may be further associated with differences in awareness to hypoglycemia. These changes in connectivity may be associated with alterations in functional outcomes among individuals with T1DM.

scholarly journals Disambiguating Pharmacodynamic Efficacy from Behavior with Neuroimaging

2016 ◽  
Vol 124 (1) ◽  
pp. 159-168 ◽  
Author(s):  
Vishvarani Wanigasekera ◽  
Melvin Mezue ◽  
Jesper Andersson ◽  
Yazhuo Kong ◽  
Irene Tracey
Keyword(s):  
Neuropathic Pain ◽  
Functional Connectivity ◽  
Drug Development ◽  
Somatosensory Cortex ◽  
Outcome Measures ◽  
Neural Activity ◽  
Resting State ◽  
Central Sensitization ◽  
Resting State Functional Connectivity ◽  
Secondary Somatosensory Cortex

Abstract Background Attrition rates of new analgesics during drug development are high; poor assay sensitivity with reliance on subjective outcome measures being a crucial factor. Methods The authors assessed the utility of functional magnetic resonance imaging with capsaicin-induced central sensitization, a mechanism relevant in neuropathic pain, for obtaining mechanism-based objective outcome measures that can differentiate an effective analgesic (gabapentin) from an ineffective analgesic (ibuprofen) and both from placebo. The authors used a double-blind, randomized phase I study design (N = 24) with single oral doses. Results Only gabapentin suppressed the secondary mechanical hyperalgesia–evoked neural response in a region of the brainstem’s descending pain modulatory system (right nucleus cuneiformis) and left (contralateral) posterior insular cortex and secondary somatosensory cortex. Similarly, only gabapentin suppressed the resting-state functional connectivity during central sensitization between the thalamus and secondary somatosensory cortex, which was plasma gabapentin level dependent. A power analysis showed that with 12 data sets, when using neural activity from the left posterior insula and right nucleus cuneiformis, a statistically significant difference between placebo and gabapentin was detected with probability ≥ 0.8. When using subjective pain ratings, this reduced to less than or equal to 0.6. Conclusions Functional imaging with central sensitization can be used as a sensitive mechanism–based assay to guide go/no-go decisions on selecting analgesics effective in neuropathic pain in early human drug development. We also show analgesic modulation of neural activity by using resting-state functional connectivity, a less challenging paradigm that is ideally suited for patient studies because it requires no task or pain provocation.

scholarly journals Brain states govern the spatio-temporal dynamics of resting-state functional connectivity

eLife ◽  
2020 ◽  
Vol 9 ◽  
Author(s):  
Felipe Aedo-Jury ◽  
Miriam Schwalm ◽  
Lara Hamzehpour ◽  
Albrecht Stroh
Keyword(s):  
Functional Connectivity ◽  
Slow Wave ◽  
Resting State ◽  
Temporal Dynamics ◽  
Cortical Activity ◽  
Wave Activity ◽  
Blood Oxygenation ◽  
Slow Wave Activity ◽  
Functional Coupling ◽  
Resting State Functional Connectivity

Previously, using simultaneous resting-state functional magnetic resonance imaging (fMRI) and photometry-based neuronal calcium recordings in the anesthetized rat, we identified blood oxygenation level-dependent (BOLD) responses directly related to slow calcium waves, revealing a cortex-wide and spatially organized correlate of locally recorded neuronal activity (Schwalm et al., 2017). Here, using the same techniques, we investigate two distinct cortical activity states: persistent activity, in which compartmentalized network dynamics were observed; and slow wave activity, dominated by a cortex-wide BOLD component, suggesting a strong functional coupling of inter-cortical activity. During slow wave activity, we find a correlation between the occurring slow wave events and the strength of functional connectivity between different cortical areas. These findings suggest that down-up transitions of neuronal excitability can drive cortex-wide functional connectivity. This study provides further evidence that changes in functional connectivity are dependent on the brain’s current state, directly linked to the generation of slow waves.

scholarly journals Individualized perturbation of the human connectome reveals reproducible biomarkers of network dynamics relevant to cognition

2020 ◽  
Vol 117 (14) ◽  
pp. 8115-8125 ◽  
Author(s):  
Recep A. Ozdemir ◽  
Ehsan Tadayon ◽  
Pierre Boucher ◽  
Davide Momi ◽  
Kelly A. Karakhanyan ◽  
...  
Keyword(s):  
Temporal Resolution ◽  
Resting State ◽  
Cognitive Abilities ◽  
Large Scale ◽  
Brain Networks ◽  
Blood Oxygenation ◽  
Neuronal Firing ◽  
Brain Dynamics ◽  
High Temporal Resolution ◽  
Indirect Measure

Large-scale brain networks are often described using resting-state functional magnetic resonance imaging (fMRI). However, the blood oxygenation level-dependent (BOLD) signal provides an indirect measure of neuronal firing and reflects slow-evolving hemodynamic activity that fails to capture the faster timescale of normal physiological function. Here we used fMRI-guided transcranial magnetic stimulation (TMS) and simultaneous electroencephalography (EEG) to characterize individual brain dynamics within discrete brain networks at high temporal resolution. TMS was used to induce controlled perturbations to individually defined nodes of the default mode network (DMN) and the dorsal attention network (DAN). Source-level EEG propagation patterns were network-specific and highly reproducible across sessions 1 month apart. Additionally, individual differences in high-order cognitive abilities were significantly correlated with the specificity of TMS propagation patterns across DAN and DMN, but not with resting-state EEG dynamics. Findings illustrate the potential of TMS-EEG perturbation-based biomarkers to characterize network-level individual brain dynamics at high temporal resolution, and potentially provide further insight on their behavioral significance.

scholarly journals Resting-state functional connectivity modulates the BOLD activation induced by nucleus accumbens stimulation in the swine brain

2019 ◽  
Author(s):  
Shinho Cho ◽  
Jan T. Hachmann ◽  
Irena Balzekas ◽  
Myung-Ho In ◽  
Lindsey G. Andres-Beck ◽  
...  
Keyword(s):  
Nucleus Accumbens ◽  
Functional Connectivity ◽  
Resting State ◽  
Large Scale ◽  
Brain Regions ◽  
Blood Oxygenation ◽  
Functional Networks ◽  
Swine Model ◽  
Resting State Functional Connectivity ◽  
The Impact

ABSTRACTWhile it is known that the clinical efficacy of deep brain stimulation (DBS) alleviates motor-related symptoms, cognitive and behavioral effects of DBS and its action mechanism on brain circuits are not clearly understood. By combining functional magnetic resonance imaging (fMRI) and DBS, we investigated the pattern of blood-oxygenation-level-dependent (BOLD) signal changes induced by stimulating the nucleus accumbens and how inter-regional resting-state functional connectivity is related with the stimulation DBS effect in a healthy swine model. We found that the pattern of stimulation-induced BOLD activation was diffused across multiple functional networks including the prefrontal, limbic, and thalamic regions, altering inter-regional functional connectivity after stimulation. Furthermore, our results showed that the strength of the DBS effect is closely related to the strength of inter-regional resting-state functional connectivity including stimulation locus and remote brain regions. Our results reveal the impact of nucleus accumbens stimulation on major functional networks, highlighting functional connectivity may mediate the modulation effect of DBS via large-scale brain networks.

scholarly journals Intrinsic Functional Connectivity As a Tool For Human Connectomics: Theory, Properties, and Optimization

2010 ◽  
Vol 103 (1) ◽  
pp. 297-321 ◽  
Author(s):  
Koene R. A. Van Dijk ◽  
Trey Hedden ◽  
Archana Venkataraman ◽  
Karleyton C. Evans ◽  
Sara W. Lazar ◽  
...  
Keyword(s):  
Functional Connectivity ◽  
Spatial Resolution ◽  
Temporal Resolution ◽  
Large Scale ◽  
Diffusion Imaging ◽  
High Angular Resolution ◽  
Resting State Functional Connectivity ◽  
Eyes Closed ◽  
Eyes Open ◽  
Task Conditions

Resting state functional connectivity MRI (fcMRI) is widely used to investigate brain networks that exhibit correlated fluctuations. While fcMRI does not provide direct measurement of anatomic connectivity, accumulating evidence suggests it is sufficiently constrained by anatomy to allow the architecture of distinct brain systems to be characterized. fcMRI is particularly useful for characterizing large-scale systems that span distributed areas (e.g., polysynaptic cortical pathways, cerebro-cerebellar circuits, cortical-thalamic circuits) and has complementary strengths when contrasted with the other major tool available for human connectomics—high angular resolution diffusion imaging (HARDI). We review what is known about fcMRI and then explore fcMRI data reliability, effects of preprocessing, analysis procedures, and effects of different acquisition parameters across six studies ( n = 98) to provide recommendations for optimization. Run length (2–12 min), run structure (1 12-min run or 2 6-min runs), temporal resolution (2.5 or 5.0 s), spatial resolution (2 or 3 mm), and the task (fixation, eyes closed rest, eyes open rest, continuous word-classification) were varied. Results revealed moderate to high test-retest reliability. Run structure, temporal resolution, and spatial resolution minimally influenced fcMRI results while fixation and eyes open rest yielded stronger correlations as contrasted to other task conditions. Commonly used preprocessing steps involving regression of nuisance signals minimized nonspecific (noise) correlations including those associated with respiration. The most surprising finding was that estimates of correlation strengths stabilized with acquisition times as brief as 5 min. The brevity and robustness of fcMRI positions it as a powerful tool for large-scale explorations of genetic influences on brain architecture. We conclude by discussing the strengths and limitations of fcMRI and how it can be combined with HARDI techniques to support the emerging field of human connectomics.

Relating Disinhibited Eating Behaviors to Resting State Functional Connectivity in Young Children

Diabetes ◽  
2018 ◽  
Vol 67 (Supplement 1) ◽  
pp. 1889-P
Author(s):  
ALLISON L.B. SHAPIRO ◽  
SUSAN L. JOHNSON ◽  
BRIANNE MOHL ◽  
GRETA WILKENING ◽  
KRISTINA T. LEGGET ◽  
...  
Keyword(s):  
Functional Connectivity ◽  
Young Children ◽  
Resting State ◽  
Eating Behaviors ◽  
Resting State Functional Connectivity ◽  
Disinhibited Eating
Sign in / Sign up

Export Citation Format

Share Document