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Here, we show that smartphone-based gaze is significantly impaired with mental fatigue, and tracks the onset and progression of fatigue. A simple model predicts mental fatigue reliably using just a few minutes of gaze data. These results suggest that smartphone-based gaze could provide a scalable, digital biomarker of mental fatigue.<\/jats:p>","DOI":"10.1038\/s41746-021-00415-6","type":"journal-article","created":{"date-parts":[[2021,3,11]],"date-time":"2021-03-11T11:03:49Z","timestamp":1615460629000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":20,"title":["Digital biomarker of mental fatigue"],"prefix":"10.1038","volume":"4","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4824-0615","authenticated-orcid":false,"given":"Vincent Wen-Sheng","family":"Tseng","sequence":"first","affiliation":[]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7174-5729","authenticated-orcid":false,"given":"Nachiappan","family":"Valliappan","sequence":"additional","affiliation":[]},{"given":"Venky","family":"Ramachandran","sequence":"additional","affiliation":[]},{"given":"Tanzeem","family":"Choudhury","sequence":"additional","affiliation":[]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6996-5519","authenticated-orcid":false,"given":"Vidhya","family":"Navalpakkam","sequence":"additional","affiliation":[]}],"member":"297","published-online":{"date-parts":[[2021,3,11]]},"reference":[{"key":"415_CR1","doi-asserted-by":"publisher","first-page":"662","DOI":"10.1038\/nrneurol.2017.117","volume":"13","author":"I-K Penner","year":"2017","unstructured":"Penner, I.-K. & Paul, F. 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