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Victoria L. Morgan, Baxter P. Rogers, Hernán F. J. González, Sarah E. Goodale and Dario J. Englot

after mTLE surgery, and early recurrence of severe, disabling seizures indicates a network inconsistent with the model; 2) variations within the presurgical network model contribute to mild seizure recurrence after surgery; and 3) these presurgical networks and their evolution are altered by surgery, which then influences the ultimate seizure freedom or recurrence. We have recently shown evidence of a presurgical functional and structural network model required for seizure freedom or improvement. 25 In that work, we identified a model mTLE connectivity network that

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Qi Yan, Nicolas Gaspard, Hitten P. Zaveri, Hal Blumenfeld, Lawrence J. Hirsch, Dennis D. Spencer and Rafeed Alkawadri

connectivity index (CI) based on the quantity and spatial extent of evoked responses to SPES and a qualitative classification of contacts. We also estimate the predictive value of focal seizures and auras induced by the low-frequency stimulation (1 Hz) used during SPES in this cohort of patients with drug-resistant epilepsy. Methods Patients and Intracranial EEG Data Acquisition We retrospectively identified patients who underwent 1-Hz stimulation at prospectively selected sites for clinical or research purposes at the Yale Comprehensive Epilepsy Center between 2003 and 2014

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Varina L. Boerwinkle, Lucia Mirea, William D. Gaillard, Bethany L. Sussman, Diana Larocque, Alexandra Bonnell, Jennifer S. Ronecker, Matthew M. Troester, John F. Kerrigan, Stephen T. Foldes, Brian Appavu, Randa Jarrar, Korwyn Williams, Angus A. Wilfong and P. David Adelson

location was not amenable to surgery. • If the rs-fMRI SOZ pattern was reported as generalized or poorly localized, meaning that the majority of the brain has equally abnormal connectivity and is declared supportive of generalized epilepsy or focal epilepsy. • If the post–rs-fMRI surgical plan changed from VNS (extracranial) to RNS (intracranial), or from VSN or RNS to a disconnective/destructive surgical approach. • If the post–rs-fMRI EPCC impression of the rs-fMRI SOZ is congruent with the plan to offer VNS, meaning both are indicating generalized or poorly localized

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Joel S. Beckett, Eric D. Brooks, Cheryl Lacadie, Brent Vander Wyk, Roger J. Jou, Derek M. Steinbacher, R. Todd Constable, Kevin A. Pelphrey and John A. Persing

, 42 To date, no studies have explored the relationship between the observed cognitive deficits and anatomical or functional differences in the brain of sNSC children. Resting-state functional connectivity MRI (rs-fcMRI) is a task-independent method to identify spatially distant brain regions that generate synchronized temporal fluctuations in the blood oxygenation level–dependent (BOLD) contrast signal. Interestingly, a number of distinct intrinsically connected brain networks have been identified using this method, and alterations within these networks are

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Fabio Grassia, Andrew V. Poliakov, Sandra L. Poliachik, Kaitlyn Casimo, Seth D. Friedman, Hillary Shurtleff, Carlo Giussani, Edward J. Novotny Jr., Jeffrey G. Ojemann and Jason S. Hauptman

F unctional connectivity MRI (fcMRI)—a method of analyzing blood oxygen level–dependent (BOLD) signal in a task-free, resting-state paradigm—can provide insight into regional connectivity in both the intact and diseased brain. In healthy controls, fcMRI reveals compartmentalization of neuronal networks into specific functional systems, such as sensorimotor, visual, auditory, dorsal attention, and default mode network (DMN). 1 , 7 While task-based fMRI is routinely used as part of the clinical presurgical evaluation of pediatric epilepsy patients, fcMRI is an

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Michael G. Hart, Stephen J. Price and John Suckling

the literature focusing on functional integration now exceeds that on functional localization. 16 One of the potential uses of rsfMRI is the mapping of functional connectivity networks, also known as resting-state networks. One method for identifying these networks is seed-based connectivity analysis (SCA), which involves extracting a time series from a selected seed region and then measuring its correlation with all other voxels in the brain ( Fig. 1 ). A summary of canonical functional connectivity networks commonly described in the literature is presented in

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Phiroz E. Tarapore, Anne M. Findlay, Sara C. LaHue, Hana Lee, Susanne M. Honma, Danielle Mizuiri, Tracy L. Luks, Geoffrey T. Manley, Srikantan S. Nagarajan and Pratik Mukherjee

through alteration of functional connectivity. 3 , 24 Functional connectivity refers to temporally correlated activity among spatially disparate brain regions and is indicative of neural communication between these regions. 1 , 11 , 30 Because of the brain's interconnectedness, a single focal lesion can have deleterious effects not just locally, but also in remote, functionally connected sites. 12 , 29 , 35 Conversely, in patients in whom no lesion is radiographically apparent, functional connectivity analysis can offer a means of quantifying a pathophysiological

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Victoria L. Morgan, Baxter P. Rogers, Adam W. Anderson, Bennett A. Landman and Dario J. Englot

-term clinical outcome. Alternatively, MRI connectivity quantification may allow examination of seizure propagation networks beyond the seizure focus. 15 We recently created a network connectivity model of mTLE by identifying the consistent connectivity properties in 8 patients with seizure-free (Engel class Ia) 1-year outcome. 35 We hypothesized that patients with networks similar to this model would have an Engel class Ia outcome at 1 year. We observed that similarity to the model predicted favorable (Engel class I–II) seizure outcome versus unfavorable (Engel class III

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Emma Sillery, Richard G. Bittar, Matthew D. Robson, Timothy E. J. Behrens, John Stein, Tipu Z. Aziz and Heidi Johansen-Berg

, stimulation of the PVG—PAG region is also thought to mediate pain relief via ascending pathways that course through the thalamus toward the neocortex. Despite these theories, data on the connectivity of the primate PVG—PAG region are sparse. Diffusion-weighted imaging is a noninvasive method of brain imaging that characterizes the diffusion properties of water. 4 In the white matter of the brain, which has directional organization, diffusion varies in different directions, and in areas of coherent fiber organization the principal diffusion direction corresponds to the

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Ann-Christine Duhaime and Steven M. Stufflebeam

The capacity engendered by the fusion of imaging, neurophysiological recording, and complex data analysis to provide new insights into disease processes and recovery of the nervous system continues to expand. In their article “Resting state magnetoencephalography functional connectivity in traumatic brain injury,” Tarapore and colleagues 4 offer a preliminary look into what is now possible with this approach, and how it may change our understanding of recovery and, eventually, allow us to monitor the effects of specific interventions. The authors