Regional abnormality of functional connectivity is associated with clinical manifestations in individuals with intractable focal epilepsy

Abstract

We explored regional functional connectivity alterations in intractable focal epilepsy brains using resting-state functional MRI. Distributions of the network parameters (corresponding to degree and eigenvector centrality) measured at each brain region for all 25 patients were significantly different from age- and sex-matched control data that were estimated by a healthy control dataset (n = 582, 18–84 years old). The number of abnormal regions whose parameters exceeded the mean + 2 SD of age- and sex-matched data for each patient were associated with various clinical parameters such as the duration of illness and seizure severity. Furthermore, abnormal regions for each patient tended to have functional connections with each other (mean ± SD = 58.6 ± 20.2%), the magnitude of which was negatively related to the quality of life. The abnormal regions distributed within the default mode network with significantly higher probability (p < 0.05) in 7 of 25 patients. We consider that the detection of abnormal regions by functional connectivity analysis using a large number of control datasets is useful for the numerical assessment of each patient’s clinical conditions, although further study is necessary to elucidate etiology-specific abnormalities.

Network structure mediates functional reorganization induced by optogenetic stimulation of non-human primate sensorimotor cortex

“…Finally, our results offer a potential explanation for how underlying network-level functional connectivity shapes the therapeutic response to stimulation. Studies have shown that aberrant functional connectivity underlies many neural disorders ( Stam et al., 2007 ; Kaiser et al., 2015 ; Nakai et al., 2021 ; Garrity et al., 2007 ), and that neural stimulation alters network-level functional connectivity ( Yazdan-Shahmorad et al., 2018 ; Keller et al., 2018 ; Huang et al., 2019 ) and can treat neural disorders ( Edwardson et al., 2013 ; Lozano and Lipsman 2013 ). As such, therapeutic response to stimulation may be a direct result of a stimulation-induced change from aberrant to healthy network-level functional connectivity.…”

“…From schizophrenia to epilepsy, aberrant network-level functional connectivity underlies a variety of neural disorders ( Garrity et al., 2007 ; Nakai et al., 2021 ; Stam et al., 2007 ). As such, the ability to modify network-level functional connectivity would be a profound development toward therapies for neural disorders.…”

Cortical network structure mediates response to stimulation: an optogenetic study in non-human primates

“…Finally, our results o↵er a potential explanation for how underlying network-level functional connectivity shapes the therapeutic response to stimulation. Studies have shown that aberrant functional connectivity underlies many neural disorders [1][2][3]52], and that neural stimulation alters network-level functional connectivity [12,17,18] and can treat neural disorders [6,31]. As such, therapeutic response to stimulation may be a direct result of a stimulation-induced change from aberrant to healthy network-level functional connectivity.…”

“…From schizophrenia to epilepsy, aberrant network-level functional connectivity underlies a variety of neural disorders [1][2][3]. As such, the ability to modify network-level functional connectivity would be a profound development towards therapies for neural disorders.…”

More than just statics: Static and temporal dynamic changes in intrinsic brain activity in unilateral temporal lobe epilepsy

“…Previous studies have focused mainly on ALFF, fALFF, or ReHo ( Zeng et al, 2013 ; Zhao et al, 2020 ), and the results were partially inconsistent. Studies on VMHC ( Xu et al, 2014 ; Shi et al, 2021 ), DC ( Liang et al, 2020 ; Nakai et al, 2021 ), and GSCorr are rare or even missing.…”