Chronic Ieeg Recordings and Interictal Spike Rate Reveal Multiscale Temporal Modulations in Seizure States
Abstract number :
1.166
Submission category :
3. Neurophysiology / 3C. Other Clinical EEG
Year :
2022
Submission ID :
2204120
Source :
www.aesnet.org
Presentation date :
12/3/2022 12:00:00 PM
Published date :
Nov 22, 2022, 05:23 AM
Authors :
Yujiang Wang, PhD – Newcastle University; Gabrielle Schroeder, PhD – Newcastle University; Philippa Karoly, Dr – University of Melbourne; Matias Maturana, Dr – University of Melbourne; Mariella Panagiotopoulou, PhD – Newcastle University; Mark Cook, Prof – University of Melbourne; Peter Taylor, PhD – Newcastle University
Rationale: Many biological processes are modulated by rhythms on circadian and multi-day timescales. In focal epilepsy, various seizure features, such as spread and duration, can change from one seizure to the next within the same patient, and appear to fluctuate over circadian and slower timescales. However, the specific timescales of this variability, as well as the specific seizure characteristics that change over time, are unclear._x000D_
Methods: Here we analysed within-patient seizure variability in 10 patients with chronic intracranial EEG recordings (185-767 days of recording time, 57-452 analysed seizures/patient). We characterised the seizure evolutions as sequences of a finite number of patient-specific functional network states. We then compared seizure state occurrence and seizure state duration to (1) time since implantation and (2) patient-specific circadian and multi-day cycles in interictal spike rate._x000D_
Results: In most patients, the occurrence or duration of at least one state was associated with the time since implantation (8 and 9 patients for state occurrence and state duration, respectively). Additionally, some patients had one or more states that were associated with phases of circadian and/or multi-day spike rate cycles (4 and 7 patients for state occurrence and state duration, respectively). A given state’s occurrence and duration were usually not associated with the same timescale._x000D_
Conclusions: Our results suggest that different time-varying factors modulate within-patient seizure evolutions over multiple timescales, with separate processes modulating a seizure state’s occurrence and duration. These findings imply that the development of time-adaptive treatments in epilepsy must account for several separate properties of epileptic seizures._x000D_
Funding: P.N.T. and Y.W. are both supported by UKRI Future Leaders Fellowships (MR/T04294X/1, MR/V026569/1).
Neurophysiology