Chronic intracranial EEG recordings and interictal spike rate reveal multiscale temporal modulations in seizure states

Abstract

Many biological processes are modulated by rhythms on circadian and multidien timescales. In focal epilepsy, various seizure features, such as spread and duration, can change from one seizure to the next within the same patient. However, the specific timescales of this variability, as well as the specific seizure characteristics that change over time, are unclear. Here, in a cross-sectional observational study, 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 characterized the seizure evolutions as sequences of a finite number of patient-specific functional seizure net..