{"database":"biostudies-literature","file_versions":[],"scores":null,"additional":{"submitter":["Kananen J"],"funding":["Pohjois-Pohjanmaan Rahasto","NIA NIH HHS","Suomen Kulttuurirahasto","NINDS NIH HHS","Suomen Lääketieteen Säätiö","Novo Nordisk Fonden","Lundbeck Foundation","Orionin Tutkimussäätiö"],"pagination":["e01090"],"full_dataset_link":["https://www.ebi.ac.uk/biostudies/studies/S-EPMC6160661"],"repository":["biostudies-literature"],"omics_type":["Unknown"],"volume":["8(9)"],"pubmed_abstract":["<h4>Introduction</h4>Functional magnetic resonance imaging (fMRI) combined with simultaneous electroencephalography (EEG-fMRI) has become a major tool in mapping epilepsy sources. In the absence of detectable epileptiform activity, the resting state fMRI may still detect changes in the blood oxygen level-dependent signal, suggesting intrinsic alterations in the underlying brain physiology.<h4>Methods</h4>In this study, we used coefficient of variation (CV) of critically sampled 10 Hz ultra-fast fMRI (magnetoencephalography, MREG) signal to compare physiological variance between healthy controls (n = 10) and patients (n = 10) with drug-resistant epilepsy (DRE).<h4>Results</h4>We showed highly significant voxel-level (p < 0.01, TFCE-corrected) increase in the physiological variance in DRE patients. At individual level, the elevations range over three standard deviations (σ) above the control mean (μ) CV<sub>MREG</sub> values solely in DRE patients, enabling patient-specific mapping of elevated physiological variance. The most apparent differences in group-level analysis are found on white matter, brainstem, and cerebellum. Respiratory (0.12-0.4 Hz) and very-low-frequency (VLF = 0.009-0.1 Hz) signal variances were most affected.<h4>Conclusions</h4>The CV<sub>MREG</sub> increase was not explained by head motion or physiological cardiorespiratory activity, that is, it seems to be linked to intrinsic physiological pulsations. We suggest that intrinsic brain pulsations play a role in DRE and that critically sampled fMRI may provide a powerful tool for their identification."],"journal":["Brain and behavior"],"pubmed_title":["Altered physiological brain variation in drug-resistant epilepsy."],"pmcid":["PMC6160661"],"funding_grant_id":["NNF13OC0004258","R01 AG048769","R155-2016-552","RF1 AG057575","R01 NS100366","RF1 NS110049"],"pubmed_authors":["Rytky S","Helakari H","Raitamaa L","Tuovinen T","LeVan P","Kiviniemi V","Nedergaard M","Raatikainen V","Huotari N","Rasila A","Kananen J","Ansakorpi H","Korhonen V","Borchardt V"],"additional_accession":[]},"is_claimable":false,"name":"Altered physiological brain variation in drug-resistant epilepsy.","description":"<h4>Introduction</h4>Functional magnetic resonance imaging (fMRI) combined with simultaneous electroencephalography (EEG-fMRI) has become a major tool in mapping epilepsy sources. In the absence of detectable epileptiform activity, the resting state fMRI may still detect changes in the blood oxygen level-dependent signal, suggesting intrinsic alterations in the underlying brain physiology.<h4>Methods</h4>In this study, we used coefficient of variation (CV) of critically sampled 10 Hz ultra-fast fMRI (magnetoencephalography, MREG) signal to compare physiological variance between healthy controls (n = 10) and patients (n = 10) with drug-resistant epilepsy (DRE).<h4>Results</h4>We showed highly significant voxel-level (p < 0.01, TFCE-corrected) increase in the physiological variance in DRE patients. At individual level, the elevations range over three standard deviations (σ) above the control mean (μ) CV<sub>MREG</sub> values solely in DRE patients, enabling patient-specific mapping of elevated physiological variance. The most apparent differences in group-level analysis are found on white matter, brainstem, and cerebellum. Respiratory (0.12-0.4 Hz) and very-low-frequency (VLF = 0.009-0.1 Hz) signal variances were most affected.<h4>Conclusions</h4>The CV<sub>MREG</sub> increase was not explained by head motion or physiological cardiorespiratory activity, that is, it seems to be linked to intrinsic physiological pulsations. We suggest that intrinsic brain pulsations play a role in DRE and that critically sampled fMRI may provide a powerful tool for their identification.","dates":{"release":"2018-01-01T00:00:00Z","publication":"2018 Sep","modification":"2026-06-14T03:19:22.975Z","creation":"2019-03-26T23:58:29Z"},"accession":"S-EPMC6160661","cross_references":{"pubmed":["30112813"],"doi":["10.1002/brb3.1090"]}}