Abstract ObjectiveSeizure unpredictability can be debilitating and dangerous for people with epilepsy. Accurate seizure forecasters could improve quality of life for those with epilepsy but must be practical for long‐term use. This study presents the first validation of a seizure‐forecasting system using ultra‐long‐term, non‐invasive wearable data. MethodsEleven participants with epilepsy were recruited for continuous monitoring, capturing heart rate and step count via wrist‐worn devices and seizures via electroencephalography (average recording duration of 337 days). Two hybrid models—combining machine learning and cycle‐based methods—were proposed to forecast seizures at both short (minutes) and long (up to 44 days) horizons. ResultsThe Seizure Warning System (SWS), designed for forecasting near‐term seizures, and the Seizure Risk System (SRS), designed for forecasting long‐term risk, both outperformed traditional models. In addition, the SRS reduced high‐risk time by 29% while increasing sensitivity by 11%. SignificanceThese improvements mark a significant advancement in making seizure forecasting more practical and effective.
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Mitigating Epilepsy by Stabilizing Linear Fractional-Order Systems
Epilepsy affects approximately 50 million people worldwide. Despite its prevalence, the recurrence of seizures can be mitigated only 70% of the time through medication. Furthermore, surgery success rates range from 30% - 70% because of our limited understanding of how a seizure starts. However, one leading hypothesis suggests that a seizure starts because of a critical transition due to an instability. Unfortunately, we lack a meaningful way to quantify this notion that would allow physicians to not only better predict seizures but also to mitigate them. Hence, in this paper, we develop a method to not only characterize the instability of seizures but also to leverage these conditions to stabilize the system underlying these seizures. Remarkably, evidence suggests that such critical transitions are associated with long-term memory dynamics, which can be captured by considering linear fractional-order systems. Subsequently, we provide for the first time tractable necessary and sufficient conditions for the global asymptotic stability of discrete-time linear fractional-order systems. Next, we propose a method to obtain a stabilizing control strategy for these systems using linear matrix inequalities. Finally, we apply our methodology to a real-world epileptic patient dataset to provide insight into mitigating epilepsy and designing future cyber-neural systems.
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- PAR ID:
- 10434246
- Date Published:
- Journal Name:
- 2023 American Control Conference (ACC)
- Issue:
- San Diego
- Page Range / eLocation ID:
- 2228 - 2233
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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