Epilepsy control using a fixed time integral super twisting sliding mode control for Pinsky-Rinzel pyramidal model...

Area of Science:

• Computational Neuroscience
• Control Systems Engineering
• Biomedical Engineering

Background:

• Epilepsy is a dynamic neurological disorder characterized by abnormal neuronal network activity.
• Rapid suppression of epileptic activity with minimal control signal is crucial for effective seizure management.
• The Pinsky-Rinzel (PR) model simulates hippocampus CA3 region dynamics, relevant to epileptic seizure occurrence.

Purpose of the Study:

• To employ a fixed-time integral super-twisting sliding-mode controller with optogenetics for epilepsy suppression.
• To assess controller robustness against parameter variations and disturbances.
• To reduce control time, achieve zero tracking error in fixed time, and converge epileptic states to normal.

Main Methods:

• Integrated a channelrhodopsin 2 (ChR2) ion current model into the Pinsky-Rinzel (PR) model for optogenetic control signal application.
• Designed a fixed-time integral super-twisting sliding-mode controller for the combined PR-ChR2 system.
• Simulated the controller's performance in suppressing epileptic activity.

Main Results:

• The proposed controller achieved a control signal of -0.7 mV.
• Tracking error to the normal desired state reached zero within 1.5 milliseconds.
• Singularity and chattering issues inherent in control systems were resolved.

Conclusions:

• The fixed-time integral super-twisting sliding-mode controller offers a safe and effective control input for the brain.
• The controller demonstrates robustness against parameter variations and external disturbances, outperforming simpler controllers.
• The study validates the efficacy of this controller for epilepsy management.