{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,2]],"date-time":"2026-05-02T23:04:24Z","timestamp":1777763064620,"version":"3.51.4"},"reference-count":49,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2020,2,21]],"date-time":"2020-02-21T00:00:00Z","timestamp":1582243200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea","doi-asserted-by":"publisher","award":["NRF-2017R1D1A1A02018479"],"award-info":[{"award-number":["NRF-2017R1D1A1A02018479"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea","doi-asserted-by":"publisher","award":["NRF-2016M3A9E1915855"],"award-info":[{"award-number":["NRF-2016M3A9E1915855"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Research on emotion recognition from facial expressions has found evidence of different muscle movements between genuine and posed smiles. To further confirm discrete movement intensities of each facial segment, we explored differences in facial expressions between spontaneous and posed smiles with three-dimensional facial landmarks. Advanced machine analysis was adopted to measure changes in the dynamics of 68 segmented facial regions. A total of 57 normal adults (19 men, 38 women) who displayed adequate posed and spontaneous facial expressions for happiness were included in the analyses. The results indicate that spontaneous smiles have higher intensities for upper face than lower face. On the other hand, posed smiles showed higher intensities in the lower part of the face. Furthermore, the 3D facial landmark technique revealed that the left eyebrow displayed stronger intensity during spontaneous smiles than the right eyebrow. These findings suggest a potential application of landmark based emotion recognition that spontaneous smiles can be distinguished from posed smiles via measuring relative intensities between the upper and lower face with a focus on left-sided asymmetry in the upper region.<\/jats:p>","DOI":"10.3390\/s20041199","type":"journal-article","created":{"date-parts":[[2020,2,21]],"date-time":"2020-02-21T10:49:16Z","timestamp":1582282156000},"page":"1199","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":30,"title":["Differences in Facial Expressions between Spontaneous and Posed Smiles: Automated Method by Action Units and Three-Dimensional Facial Landmarks"],"prefix":"10.3390","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3247-0280","authenticated-orcid":false,"given":"Seho","family":"Park","sequence":"first","affiliation":[{"name":"Interdisciplinary Program in Cognitive Science, Seoul National University, Seoul 08826, Korea"},{"name":"Dental Research Institute, Seoul National University, School of Dentistry, Seoul 08826, Korea"},{"name":"Department of Psychiatry, Seoul National University College of Medicine &amp; SMG-SNU Boramae Medical Center, Seoul 03080, Korea"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0634-1119","authenticated-orcid":false,"given":"Kunyoung","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Computer Science, Sangmyung University, Seoul 03016, Korea"}]},{"given":"Jae-A","family":"Lim","sequence":"additional","affiliation":[{"name":"Department of Psychiatry, Seoul National University College of Medicine &amp; SMG-SNU Boramae Medical Center, Seoul 03080, Korea"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7135-3872","authenticated-orcid":false,"given":"Hyunwoong","family":"Ko","sequence":"additional","affiliation":[{"name":"Interdisciplinary Program in Cognitive Science, Seoul National University, Seoul 08826, Korea"},{"name":"Dental Research Institute, Seoul National University, School of Dentistry, Seoul 08826, Korea"},{"name":"Department of Psychiatry, Seoul National University College of Medicine &amp; SMG-SNU Boramae Medical Center, Seoul 03080, Korea"}]},{"given":"Taehoon","family":"Kim","sequence":"additional","affiliation":[{"name":"Seoul National University College of Medicine, Seoul 03080, Korea"}]},{"given":"Jung-In","family":"Lee","sequence":"additional","affiliation":[{"name":"Seoul National University College of Medicine, Seoul 03080, Korea"}]},{"given":"Hakrim","family":"Kim","sequence":"additional","affiliation":[{"name":"Seoul National University College of Medicine, Seoul 03080, Korea"}]},{"given":"Seong-Jae","family":"Han","sequence":"additional","affiliation":[{"name":"Seoul National University College of Medicine, Seoul 03080, Korea"}]},{"given":"Jeong-Shim","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Psychiatry, Seoul National University College of Medicine &amp; SMG-SNU Boramae Medical Center, Seoul 03080, Korea"}]},{"given":"Soowon","family":"Park","sequence":"additional","affiliation":[{"name":"Department of Education, Sejong University, Seoul 05006, Korea"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5893-3124","authenticated-orcid":false,"given":"Jun-Young","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Psychiatry, Seoul National University College of Medicine &amp; SMG-SNU Boramae Medical Center, Seoul 03080, Korea"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6504-3333","authenticated-orcid":false,"given":"Eui Chul","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Human Centered Artificial Intelligence, Sangmyung University, Seoul 03016, Korea"}]}],"member":"1968","published-online":{"date-parts":[[2020,2,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"41","DOI":"10.1007\/BF02876972","article-title":"Neuropsychological Aspects of Facial Asymmetry during Emotional Expression: A Review of the Normal Adult Literature","volume":"7","author":"Borod","year":"1997","journal-title":"Neuropsychol. 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