{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,11]],"date-time":"2026-02-11T19:12:40Z","timestamp":1770837160851,"version":"3.50.1"},"reference-count":44,"publisher":"Public Library of Science (PLoS)","issue":"2","license":[{"start":{"date-parts":[[2026,2,11]],"date-time":"2026-02-11T00:00:00Z","timestamp":1770768000000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001700","name":"The Ministry of Education, Culture, Sports, Sciences and Technology","doi-asserted-by":"crossref","award":["17H06454"],"award-info":[{"award-number":["17H06454"]}],"id":[{"id":"10.13039\/501100001700","id-type":"DOI","asserted-by":"crossref"}]},{"DOI":"10.13039\/501100001691","name":"Japan Society for the Promotion of Science","doi-asserted-by":"publisher","award":["23K25752"],"award-info":[{"award-number":["23K25752"]}],"id":[{"id":"10.13039\/501100001691","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001691","name":"Japan Society for the Promotion of Science","doi-asserted-by":"publisher","award":["19K14492"],"award-info":[{"award-number":["19K14492"]}],"id":[{"id":"10.13039\/501100001691","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001691","name":"Japan Society for the Promotion of Science","doi-asserted-by":"publisher","award":["24H00178"],"award-info":[{"award-number":["24H00178"]}],"id":[{"id":"10.13039\/501100001691","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS One"],"abstract":"<jats:p>The Coronavirus disease 2019 pandemic has significantly altered infants\u2019 social environments. In Japan, people continued to wear face masks outdoors for approximately three years following the onset of the pandemic. Consequently, most infants born during this period have limited exposure to unmasked faces. However, how such changes in face experience may influence the development of face processing during infancy remains unclear. In the present study, we investigated visual preferences for mothers\u2019 faces versus unfamiliar female faces in 5\u20138-month-old infants born during the pandemic in three regions of Japan (Tokyo in Experiment 1 and provincial cities in Experiment 2). Infants\u2019 preferences for their mothers\u2019 faces were evaluated under two conditions: when both faces were unmasked (unmasked condition) and when both wore face masks (masked condition). Additionally, parents completed questionnaires reporting their infant\u2019s exposure to unmasked faces in daily life. Group-level analysis showed that infants in provincial cities significantly preferred their mothers\u2019 faces under both masked and unmasked conditions. By contrast, infants in Tokyo showed a significant preference for their mothers\u2019 faces only in the masked condition. Moreover, individual-level analyses revealed that infants with greater exposure to unmasked faces were more likely to prefer their mothers in the unmasked condition. These findings suggest that infants\u2019 daily visual experiences, particularly with unmasked faces, may modulate their developing preferences for their mothers\u2019 faces, highlighting the impact of social context on early face processing.<\/jats:p>","DOI":"10.1371\/journal.pone.0340620","type":"journal-article","created":{"date-parts":[[2026,2,11]],"date-time":"2026-02-11T18:23:41Z","timestamp":1770834221000},"page":"e0340620","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":0,"title":["Variations in face experiences during the COVID-19 pandemic affect infants\u2019 preference for their mother\u2019s face"],"prefix":"10.1371","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5218-1403","authenticated-orcid":true,"given":"Megumi","family":"Kobayashi","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Machi","family":"Sugai","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"So","family":"Kanazawa","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Masami K.","family":"Yamaguchi","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"340","published-online":{"date-parts":[[2026,2,11]]},"reference":[{"issue":"4","key":"pone.0340620.ref001","doi-asserted-by":"crossref","first-page":"369","DOI":"10.1016\/j.jped.2020.08.008","article-title":"The potential impact of the COVID-19 pandemic on child growth and development: a systematic review","volume":"97","author":"LA de 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