Abstract
SummaryRecent evidence suggests that three specific brain networks show state‐dependent levels of synchronization before, during, and after episodes of generalized spike‐wave discharges (GSW) in patients with genetic generalized epilepsy (GGE). Here, we investigate whether synchronization in these networks differs between patients with GGE (n = 13), their unaffected first‐degree relatives (n = 17), and healthy controls (n = 18). All subjects underwent two 10‐minute simultaneous electroencephalographic–functional magnetic resonance imaging (fMRI) recordings without GSW. Whole‐brain data were divided into 90 regions, and blood oxygen level–dependent (BOLD) phase synchrony in a 0.04–0.07‐Hz band was estimated between all pairs of regions. Three networks were defined: (1) the network with highest synchrony during GSW events, (2) a sensorimotor network, and (3) an occipital network. Average synchrony (mean node degree) was inferred across each network over time. Notably, synchrony was significantly higher in the sensorimotor network in patients and in unaffected relatives, compared to controls. There was a trend toward higher synchrony in the GSW network in patients and in unaffected relatives. There was no difference between groups for the occipital network. Our findings provide evidence that elevated fMRI BOLD synchrony in a sensorimotor network is a state‐independent endophenotype of GGE, present in patients in the absence of GSW, and present in unaffected relatives.
Highlights
There is strong evidence for the heritability of genetic generalized epilepsy (GGE).[1]
We found that synchrony in specific networks, observed with blood oxygen level–dependent (BOLD) functional magnetic resonance imaging (fMRI) and simultaneous EEG, varies dynamically around the time of generalized spike‐wave (GSW) events observed in EEG,[8] apparently anticipating the onset of generalized spike‐ wave discharges (GSW) by several seconds
We have previously acquired and published EEG fMRI data from 21 patients diagnosed with juvenile myoclonic epilepsy (JME) or generalized tonic‐clonic seizures only (GTCSO)[8]; here, we include the 13 in whom fMRI runs were entirely free of GSW, in addition to 18 healthy controls reported in the same prior study, and 17 unaffected first‐degree relatives collected during the same period of time, but not previously reported
Summary
There is strong evidence for the heritability of genetic (or idiopathic) generalized epilepsy (GGE).[1] An important. Concept emerging in studies of disease inheritance is endophenotype,[2] a heritable trait with a simpler genetic basis than the full disorder, which may be present in family members who do not have the disease. There is increasing interest in identifying endophenotypes in epilepsy. A few studies have already demonstrated that GGE may have a distinct endophenotype.
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
