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Cell. Neurosci."],"abstract":"<jats:p>Eye-trackers are widely used to study nervous system dynamics and neuropathology. Despite this broad utility, eye-tracking remains expensive, hardware-intensive, and proprietary, limiting its use to high-resource facilities. It also does not easily allow for real-time analysis and closed-loop design to link eye movements to neural activity. To address these issues, we developed an open-source eye-tracker \u2013 EyeLoop \u2013 that uses a highly efficient vectorized pupil detection method to provide uninterrupted tracking and fast online analysis with high accuracy on par with popular eye tracking modules, such as DeepLabCut. This Python-based software easily integrates custom functions using code modules, tracks a multitude of eyes, including in rodents, humans, and non-human primates, and operates at more than 1,000 frames per second on consumer-grade hardware. In this paper, we demonstrate EyeLoop\u2019s utility in an open-loop experiment and in biomedical disease identification, two common applications of eye-tracking. With a remarkably low cost and minimum setup steps, EyeLoop makes high-speed eye-tracking widely accessible.<\/jats:p>","DOI":"10.3389\/fncel.2021.779628","type":"journal-article","created":{"date-parts":[[2021,12,9]],"date-time":"2021-12-09T12:59:18Z","timestamp":1639054758000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":12,"title":["EyeLoop: An Open-Source System for High-Speed, Closed-Loop Eye-Tracking"],"prefix":"10.3389","volume":"15","author":[{"given":"Simon","family":"Arvin","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rune Nguyen","family":"Rasmussen","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Keisuke","family":"Yonehara","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2021,12,9]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"1","DOI":"10.16910\/jemr.3.3.6","article-title":"Sampling frequency and eye-tracking measures: how speed affects durations, latencies, and more.","volume":"3","author":"Andersson","year":"2010","journal-title":"J. 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