Background: We compared resting-state functional connectivity (RSFC) among limbic and temporal lobe regions between patients with medial temporal lobe epilepsy (mTLE) and healthy control subjects to identify imaging evidence of functional networks related to seizure frequency, age of seizure onset, and duration of epilepsy. Methods: Twelve patients with drug-resistant, unilateral medial temporal lobe epilepsy and 12 healthy control subjects matched for age, sex, and handedness participated in the imaging experiments. We used network-based statistics to compare functional connectivity graphs in patients with mTLE and healthy controls to investigate the relationship between functional connectivity abnormalities and seizure frequency. Results: Among mTLE patients, we found functional network abnormalities throughout the limbic system, but primarily in the hemisphere ipsilateral to the seizure focus. The RSFCs between ipsilateral hypothalamus and ventral anterior cingulate cortex and between ipsilateral subiculum and contralateral posterior cingulate cortex were highly correlated with seizure frequency. Discussion: These findings suggest that in mTLE, changes in limbic networks ipsilateral to the epileptic focus are common. The pathological changes in connectivity between cingulate cortex, hypothalamus and subiculum ipsilateral to the seizure focus were correlated with increased seizure frequency.
Bibliographical noteFunding Information:
This study was funded by National Institutes of Health (R01 NS092882, UH2-NS95495), Project LQ1605 National Program of Sustainability II (MEYS CR), and European Regional Development Fund - Project FNUSA - ICRC (CZ.1.05/1.1.00/02.0123). PC is supported by the National Institutes of Health under award R01 MH113700. The content of this publication is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.
© 2019 Jo, Kenney-Jung, Balzekas, Welker, Jones, Croarkin, Benarroch and Worrell. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
- Functional magnetic resonance imaging
- Limbic system
- Medial temporal lobe epilepsy
- Network-based statistics
- Partial seizure