{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T01:46:11Z","timestamp":1760147171248,"version":"build-2065373602"},"reference-count":45,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2023,1,14]],"date-time":"2023-01-14T00:00:00Z","timestamp":1673654400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"European Union\u2019s H2020 Marie Sk\u0142odowska-Curie Actions","award":["765298, 2017"],"award-info":[{"award-number":["765298, 2017"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Most well-established eye-tracking research paradigms adopt remote systems, which typically feature regular flat screens of limited width. Limitations of current eye-tracking methods over a wide area include calibration, the significant loss of data due to head movements, and the reduction of data quality over the course of an experimental session. Here, we introduced a novel method of tracking gaze and head movements that combines the possibility of investigating a wide field of view and an offline calibration procedure to enhance the accuracy of measurements. A 4-camera Smart Eye Pro system was adapted for infant research to detect gaze movements across 126\u00b0 of the horizontal meridian. To accurately track this visual area, an online system calibration was combined with a new offline gaze calibration procedure. Results revealed that the proposed system successfully tracked infants\u2019 head and gaze beyond the average screen size. The implementation of an offline calibration procedure improved the validity and spatial accuracy of measures by correcting a systematic top-right error (1.38\u00b0 mean horizontal error and 1.46\u00b0 mean vertical error). This approach could be critical for deriving accurate physiological measures from the eye and represents a substantial methodological advance for tracking looking behaviour across both central and peripheral regions. The offline calibration is particularly useful for work with developing populations, such as infants, and for people who may have difficulties in following instructions.<\/jats:p>","DOI":"10.3390\/s23020972","type":"journal-article","created":{"date-parts":[[2023,1,16]],"date-time":"2023-01-16T05:30:07Z","timestamp":1673847007000},"page":"972","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Offline Calibration for Infant Gaze and Head Tracking across a Wide Horizontal Visual Field"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3551-9446","authenticated-orcid":false,"given":"Chiara","family":"Capparini","sequence":"first","affiliation":[{"name":"Center for Research in Cognition & Neuroscience (CRCN), Universit\u00e9 Libre de Bruxelles, 1050 Brussels, Belgium"},{"name":"Department of Psychology, Lancaster University, Lancaster LA1 4YF, UK"}]},{"given":"Michelle P. S.","family":"To","sequence":"additional","affiliation":[{"name":"Department of Psychology, Lancaster University, Lancaster LA1 4YF, UK"}]},{"given":"Cl\u00e9ment","family":"Dardenne","sequence":"additional","affiliation":[{"name":"Research and AI Labs, Smart Eye AB, 413 27 Gothenburg, Sweden"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2774-6975","authenticated-orcid":false,"given":"Vincent M.","family":"Reid","sequence":"additional","affiliation":[{"name":"School of Psychology, University of Waikato, Hamilton 3240, New Zealand"}]}],"member":"1968","published-online":{"date-parts":[[2023,1,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"126","DOI":"10.1111\/j.1532-7078.2011.00097.x","article-title":"Infant Eyes: A Window on Cognitive Development","volume":"17","author":"Aslin","year":"2011","journal-title":"Infancy"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"359","DOI":"10.1080\/15248372.2015.1135801","article-title":"Pupillometry in Infancy Research","volume":"17","author":"Hepach","year":"2016","journal-title":"J. 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