A DC-Sensitive Video/ Electrophysiology Monitoring Unit for Long-Term Continuous Study of Seizures and Seizure-Associated Spreading Depolarization in a Rat Model

There has been a long-term need for a low-cost, highly efficient, and high-fidelity epilepsy monitoring unit (EMU) suitable for synchronized multimodal home-cage monitoring of small-animal models of epilepsy and spreading depolarization. We present an accessible, scalable, highly space-and energy-efficient EMU capable of fulfilling chronic, continuous, synchronized, multiple-animal monitoring jobs. Each rig within the EMU can provide 16-channel high-fidelity, DC-sensitive biopotential recordings, head acceleration monitoring, voltammetry applications, and synchronized video recording on one freely moving rat. We present the overall EMU architecture design and subsystem details in each recording rig. We demonstrate long-term continuous in vivo recordings of spontaneous seizure and seizure-associated spreading depolarization from freely moving rats (male, 21; female, 6) prepared under the tetanus toxin model of temporal lobe epilepsy.