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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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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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Kaitlyn Casimo, Fabio Grassia, Sandra L. Poliachik, Edward Novotny, Andrew Poliakov and Jeffrey G. Ojemann

F unctional connectivity describes coincident activity between brain regions. This may be the result of direct synchrony between brain regions, or of a common input similarly influencing multiple brain regions. It may support synaptic formation and maintenance, or provide a mechanism for cognitive integration and information transfer. 11 , 27 The corpus callosum provides direct anatomical connections mostly between homologous regions, but its role in maintaining functional connectivity has not been fully established. Homologous sites in opposite hemispheres are

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Naoki Tani, Takahide Yaegaki, Akio Nishino, Kenta Fujimoto, Hiroyuki Hashimoto, Kaoru Horiuchi, Mitsuhisa Nishiguchi and Haruhiko Kishima

examine brain connectivity, so-called functional connectivity (FC), and its relation to cognition and behavior. In particular, rs-fMRI studies have elucidated changes in the default mode network (DMN) associated with cognitive impairment in several disorders, e.g., Alzheimer’s disease, multiple sclerosis, traumatic brain injury, idiopathic normal pressure hydrocephalus, and attention deficit hyperactivity disorder. 5 , 6 , 17 , 20 , 23 , 32 Furthermore, recent studies have pinpointed the DMN alteration involved in cognitive decline in patients with cerebral vascular

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

, the objectives of the present work were designed to examine our third hypothesis. First, we characterized and quantified postsurgical functional connectivity (FC) in mTLE. Second, we compared postsurgical FC network changes to seizure outcome to identify possible regions responsible for postsurgical seizure recurrence. Third, we compared postsurgical network changes to the type of surgery performed. Last, we determined the relationship between postsurgical FC change and presurgical disease parameters to identify possible regions where postsurgical changes may

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Steven M. Stufflebeam, Hesheng Liu, Jorge Sepulcre, Naoaki Tanaka, Randy L. Buckner and Joseph R. Madsen

epileptic focus remains unclear, other diagnostic tests can be performed such as FDG-PET, ictal SPECT, and/or MEG. 4 , 14 If uncertainty remains, iEEG with subdural grids or depth electrodes may aid in decision making. 15 An accurate noninvasive and high–spatial resolution method to localize epileptic foci thus remains a major challenge. Functional connectivity MR imaging (fcMR imaging) is based on correlating spontaneous fluctuations in blood flow across the brain, and these fluctuations are ultimately linked to neural activity. 2 , 6 , 27 Previously, we and others

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Matthieu Vassal, Céline Charroud, Jérémy Deverdun, Emmanuelle Le Bars, François Molino, Francois Bonnetblanc, Anthony Boyer, Anirban Dutta, Guillaume Herbet, Sylvie Moritz-Gasser, Alain Bonafé, Hugues Duffau and Nicolas Menjot de Champfleur

activity. Thus, different regions of the brain are considered as working together when the temporal courses of their BOLD signals are correlated. Hence, using this technique, functional connectivity studies can focus on the concept of networks integrating different regions of the brain. These regions can be either predetermined based on the literature (hypothesis-driven studies) or selected on the basis of a data-driven independent component analysis. 22 The correlations in time between the associated time series are the basis of functional studies and allow

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Erik H. Middlebrooks, Sanjeet S. Grewal, Matthew Stead, Brian N. Lundstrom, Gregory A. Worrell and Jamie J. Van Gompel

variability in outcomes exists. 18 , 44 One potential cause for outcome variation is inadequate DBS targeting: for instance, approximately 10% of electrodes were not within the ANT in the SANTE trial and the Medtronic Registry for Epilepsy (MORE) study. 30 , 50 Suggested improvements in direct ANT targeting have been proposed; 10 , 40 however, insufficiencies in direct structural targeting in DBS have been previously illustrated. 36 , 37 In this pilot study, we aimed to assess potential differences in resting-state functional connectivity profiles from volumes of tissue

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Alberto Isla, Bartolomé Bejarano, Carmen Morales, Concepción Pérez Conde and Carlos Avendaño

–295, 1990 8. Carlstedt TP , Hallin RG , Hedström KG , et al : Functional recovery in primates with brachial plexus injury after spinal cord implantation of avulsed ventral roots. J Neurol Neurosurg Psychiatry 56 : 649 – 654 , 1993 Carlstedt TP, Hallin RG, Hedström KG, et al: Functional recovery in primates with brachial plexus injury after spinal cord implantation of avulsed ventral roots. J Neurol Neurosurg Psychiatry 56: 649–654, 1993 9. Cheng H , Shoung HM , Wu ZA , et al : Functional connectivity of the transected brachial plexus after

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Constantin Tuleasca, Thomas A. W. Bolton, Jean Régis, Elena Najdenovska, Tatiana Witjas, Nadine Girard, Francois Delaire, Marion Vincent, Mohamed Faouzi, Jean-Philippe Thiran, Meritxell Bach Cuadra, Marc Levivier and Dimitri Van De Ville

functional connectivity (dFC). 31 Therefore, we use a recent methodology, termed coactivation pattern (CAP) analysis, which allows us to investigate how a particular seed region interacts with the rest of the brain in a time-varying manner. 26 To investigate this, we examined a subpart of the right extrastriate cortex (Brodmann area [BA] 19, including V3, V4, and V5) as a unique region of interest (ROI). It was chosen from our previously published data 37 , 40 (further confirmed by task-based studies 1 ), given its functional connectivity with the cerebellum lobule VI