http://www.nitrc.org/forum/forum.php?forum_id=7129 <table border="0" width="100%"><tr><td align="left"/></tr></table> <p><b>Simultaneous Intracranial EEG-fMRI Shows Inter-Modality Correlation in Time-Resolved Connectivity Within Normal Areas but Not Within Epileptic Regions.</b></p> <p>Brain Topogr. 2017 Feb 13;:</p> <p>Authors: Ridley B, Wirsich J, Bettus G, Rodionov R, Murta T, Chaudhary U, Carmichael D, Thornton R, Vulliemoz S, McEvoy A, Wendling F, Bartolomei F, Ranjeva JP, Lemieux L, Guye M</p> <p>Abstract<br/> For the first time in research in humans, we used simultaneous icEEG-fMRI to examine the link between connectivity in haemodynamic signals during the resting-state (rs) and connectivity derived from electrophysiological activity in terms of the inter-modal connectivity correlation (IMCC). We quantified IMCC in nine patients with drug-resistant epilepsy (i) within brain networks in 'healthy' non-involved cortical zones (NIZ) and (ii) within brain networks involved in generating seizures and interictal spikes (IZ1) or solely spikes (IZ2). Functional connectivity (h (2) ) estimates for 10 min of resting-state data were obtained between each pair of electrodes within each clinical zone for both icEEG and fMRI. A sliding window approach allowed us to quantify the variability over time of h (2) (vh (2)) as an indicator of connectivity dynamics. We observe significant positive IMCC for h (2) and vh (2), for multiple bands in the NIZ only, with the strongest effect in the lower icEEG frequencies. Similarly, intra-modal h (2) and vh (2) were found to be differently modified as a function of different epileptic processes: compared to NIZ, [Formula: see text] was higher in IZ1, but lower in IZ2, while [Formula: see text] showed the inverse pattern. This corroborates previous observations of inter-modal connectivity discrepancies in pathological cortices, while providing the first direct invasive and simultaneous comparison in humans. We also studied time-resolved FC variability multimodally for the first time, finding that IZ1 shows both elevated internal [Formula: see text] and less rich dynamical variability, suggesting that its chronic role in epileptogenesis may be linked to greater homogeneity in self-sustaining pathological oscillatory states.<br/> </p><p>PMID: 28194612 [PubMed - as supplied by publisher]</p> en-us Copyright 2000-2026 NITRC OSI Wed, 06 May 2026 8:10:14 GMT http://blogs.law.harvard.edu/tech/rss NITRC RSS generator