{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,6]],"date-time":"2026-05-06T03:30:05Z","timestamp":1778038205373,"version":"3.51.4"},"reference-count":92,"publisher":"MDPI AG","issue":"14","license":[{"start":{"date-parts":[[2021,7,16]],"date-time":"2021-07-16T00:00:00Z","timestamp":1626393600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Ministry of Education through National Research Foundation of Korea","award":["NRF-2017R1D1A1A02018479"],"award-info":[{"award-number":["NRF-2017R1D1A1A02018479"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Facial expressions are well known to change with age, but the quantitative properties of facial aging remain unclear. In the present study, we investigated the differences in the intensity of facial expressions between older (n = 56) and younger adults (n = 113). In laboratory experiments, the posed facial expressions of the participants were obtained based on six basic emotions and neutral facial expression stimuli, and the intensities of their faces were analyzed using a computer vision tool, OpenFace software. Our results showed that the older adults expressed strong expressions for some negative emotions and neutral faces. Furthermore, when making facial expressions, older adults used more face muscles than younger adults across the emotions. These results may help to understand the characteristics of facial expressions in aging and can provide empirical evidence for other fields regarding facial recognition.<\/jats:p>","DOI":"10.3390\/s21144858","type":"journal-article","created":{"date-parts":[[2021,7,18]],"date-time":"2021-07-18T21:18:52Z","timestamp":1626643132000},"page":"4858","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["Changes in Computer-Analyzed Facial Expressions with Age"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7135-3872","authenticated-orcid":false,"given":"Hyunwoong","family":"Ko","sequence":"first","affiliation":[{"name":"Interdisciplinary Program in Cognitive Science, Seoul National University, Seoul 08826, Korea"},{"name":"Department of Psychiatry, SMG-SNU Boramae Medical Center, Seoul National University College of Medicine, Seoul 03080, Korea"},{"name":"Dental Research Institute, School of Dentistry, Seoul National University, Seoul 08826, Korea"}]},{"given":"Kisun","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Psychiatry, SMG-SNU Boramae Medical Center, Seoul National University College of Medicine, Seoul 03080, Korea"}]},{"given":"Minju","family":"Bae","sequence":"additional","affiliation":[{"name":"Interdisciplinary Program in Cognitive Science, Seoul National University, Seoul 08826, Korea"},{"name":"Department of Psychiatry, SMG-SNU Boramae Medical Center, Seoul National University College of Medicine, Seoul 03080, Korea"}]},{"given":"Myo-Geong","family":"Seo","sequence":"additional","affiliation":[{"name":"Department of Psychiatry, SMG-SNU Boramae Medical Center, Seoul National University College of Medicine, Seoul 03080, Korea"}]},{"given":"Gieun","family":"Nam","sequence":"additional","affiliation":[{"name":"Department of Psychiatry, SMG-SNU Boramae Medical Center, Seoul National University College of Medicine, Seoul 03080, Korea"}]},{"given":"Seho","family":"Park","sequence":"additional","affiliation":[{"name":"Behavioral Neuroscience Program, School of Medicine, Boston University, Boston, MA 02101, USA"}]},{"given":"Soowon","family":"Park","sequence":"additional","affiliation":[{"name":"Division of Teacher Education, College of Liberal Arts and Interdisciplinary Studies, Kyonggi University, Suwon 16200, Korea"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3136-5956","authenticated-orcid":false,"given":"Jungjoon","family":"Ihm","sequence":"additional","affiliation":[{"name":"Interdisciplinary Program in Cognitive Science, Seoul National University, Seoul 08826, Korea"},{"name":"Dental Research Institute, School of Dentistry, Seoul National University, Seoul 08826, Korea"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5893-3124","authenticated-orcid":false,"given":"Jun-Young","family":"Lee","sequence":"additional","affiliation":[{"name":"Interdisciplinary Program in Cognitive Science, Seoul National University, Seoul 08826, Korea"},{"name":"Department of Psychiatry, SMG-SNU Boramae Medical Center, Seoul National University College of Medicine, Seoul 03080, Korea"}]}],"member":"1968","published-online":{"date-parts":[[2021,7,16]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"644","DOI":"10.1037\/h0077071","article-title":"Nonverbal communication of affect in children","volume":"31","author":"Buck","year":"1975","journal-title":"J. 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