Auditory Stimuli Can Interrupt Spike-wave Discharges in a Genetic Absence Epilepsy Rodent Model
Abstract number :
2.05
Submission category :
3. Neurophysiology / 3F. Animal Studies
Year :
2022
Submission ID :
2204093
Source :
www.aesnet.org
Presentation date :
12/4/2022 12:00:00 PM
Published date :
Nov 22, 2022, 05:23 AM
Authors :
Xinyuan Zheng, MA – Yale University; Cian McCafferty, PhD – University College Cork; Renee Tung, BS – Yale University; Benjamin Gruenbaum, MD PhD – Yale University; Hal blumenfeld, MD PhD – Yale University
Rationale: Absence seizures are characterized by spike-wave discharges (SWDs) on the electroencephalogram (EEG) with apparent impaired consciousness. Previous work in human epilepsy patients and in animal models suggests that external sensory stimuli can sometimes interrupt absence seizures and restore responsiveness. However, the ability to interrupt seizures has not been rigorously quantified, leaving several questions about physiological and behavioral factors that may contribute to seizure interruption. Therefore, our goal was to investigate these factors during the interruption of SWDs using an auditory perception task in a validated rodent model of absence epilepsy.
Methods: Genetic Absence Epilepsy Rats from Strasbourg (GAERS) were head-fixed and conditioned to respond to sound stimuli by licking at a reward port. Fronto-parietal EEG was recorded and used to label SWDs in the rats. The stimuli were presented at irregular intervals of between 120 and 240 seconds or upon automated seizure detection. We performed Fourier analysis and quantified frequency bands of the collected EEG power, and analyzed behavioral licking responses.
Results: We found that of 427 SWDs recorded from GAERS, 200 were terminated within 1 second of an auditory stimulus presentation. The number of SWDs terminated within 1s of stimuli was disproportionally high compared to SWDs that ended at longer times after the auditory stimulus. This was true even if brief ( < 3s) seizures were removed from the analysis. Therefore, we defined SWDs ending within 1s of the stimulus to be “interrupted”. We next compared EEG physiology and behavior between interrupted and non-interrupted seizures. We found no statistically significant differences in EEG power in the frequency range of waves (5-9 Hz) or spikes (15-100 Hz) around the time of stimulus onset, seizure onset or seizure offset. Additionally, by analyzing the lick rates of the animals 10s prior to seizure onset, we found no statistically significant behavioral differences between the two groups prior to the initiation of interrupted vs. non-interrupted seizures.
Neurophysiology