Seizure event detection using intravital two-photon calcium imaging data

Abstract

9 Significance: Genetic cellular calcium imaging has emerged as a powerful tool to investigate how different types of 10 neurons interact at the microcircuit level to produce seizure activity, with newfound potential to understand epilepsy. 11 Although many methods exist to measure seizure-related activity in traditional electrophysiology, few yet exist for 12 calcium imaging. 13 Aim: To demonstrate an automated algorithmic framework to detect seizure-related events using calcium imaging-14 including the detection of pre-ictal spike events, propagation of the seizure wavefront, and terminal spreading waves 15 for both population-level activity and that of individual cells. 16 Approach: We developed an algorithm for precise recruitment detection of population and individual cells during 17 seizure-associated events, which broadly leverages averaged population activity and high-magnitude slope features to 18 detect single-cell pre-ictal spike and seizure recruitment. We applied this method to data recorded using awake in vivo 19 two-photon calcium imaging during pentylenetetrazol induced seizures in mice. 20 Results: We demonstrate that our detected recruitment times are concordant with visually identified labels provided 21 by an expert reviewer and are sufficiently accurate to model the spatiotemporal progression of seizure-associated 22 traveling waves. 23 Conclusions: Our algorithm enables accurate cell recruitment detection and will serve as a useful tool for researchers 24 investigating seizure dynamics using calcium imaging. 25 26