{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,28]],"date-time":"2026-02-28T18:19:26Z","timestamp":1772302766798,"version":"3.50.1"},"reference-count":24,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2023,1,19]],"date-time":"2023-01-19T00:00:00Z","timestamp":1674086400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"JSPS KAKENHI","award":["JP17K13088"],"award-info":[{"award-number":["JP17K13088"]}]},{"name":"JSPS KAKENHI","award":["JP19H01124"],"award-info":[{"award-number":["JP19H01124"]}]},{"name":"JSPS KAKENHI","award":["JPMJCR17A5"],"award-info":[{"award-number":["JPMJCR17A5"]}]},{"name":"JST CREST","award":["JP17K13088"],"award-info":[{"award-number":["JP17K13088"]}]},{"name":"JST CREST","award":["JP19H01124"],"award-info":[{"award-number":["JP19H01124"]}]},{"name":"JST CREST","award":["JPMJCR17A5"],"award-info":[{"award-number":["JPMJCR17A5"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Pleasant touching is an important aspect of social interactions that is widely used as a caregiving technique. To address the problems resulting from a lack of available human caregivers, previous research has attempted to develop robots that can perform this kind of pleasant touch. However, it remains unclear whether robots can provide such a pleasant touch in a manner similar to humans. To investigate this issue, we compared the effect of the speed of gentle strokes on the back between human and robot agents on the emotional responses of human participants (n = 28). A robot or a human stroked on the participants\u2019 back at two different speeds (i.e., 2.6 and 8.5 cm\/s). The participants\u2019 subjective (valence and arousal ratings) and physiological (facial electromyography (EMG) recorded from the corrugator supercilii and zygomatic major muscles and skin conductance response) emotional reactions were measured. The subjective ratings demonstrated that the speed of 8.5 cm\/s was more pleasant and arousing than the speed of 2.6 cm\/s for both human and robot strokes. The corrugator supercilii EMG showed that the speed of 8.5 cm\/s resulted in reduced activity in response to both human and robot strokes. These results demonstrate similar speed-dependent modulations of stroke on subjective and physiological positive emotional responses across human and robot agents and suggest that robots can provide a pleasant touch similar to that of humans.<\/jats:p>","DOI":"10.3390\/s23031136","type":"journal-article","created":{"date-parts":[[2023,1,19]],"date-time":"2023-01-19T01:33:51Z","timestamp":1674092031000},"page":"1136","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Pleasant Stroke Touch on Human Back by a Human and a Robot"],"prefix":"10.3390","volume":"23","author":[{"given":"Tomoki","family":"Ishikura","sequence":"first","affiliation":[{"name":"Division of Information Science, Nara Institute of Science and Technology, Ikoma 630-0192, Japan"}]},{"given":"Yuki","family":"Kitamura","sequence":"additional","affiliation":[{"name":"Division of Information Science, Nara Institute of Science and Technology, Ikoma 630-0192, Japan"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5335-1272","authenticated-orcid":false,"given":"Wataru","family":"Sato","sequence":"additional","affiliation":[{"name":"Psychological Process Research Team, Guardian Robot Project, RIKEN, Seika-cho, Soraku-gun, Kyoto 619-0228, Japan"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7457-2878","authenticated-orcid":false,"given":"Jun","family":"Takamatsu","sequence":"additional","affiliation":[{"name":"Division of Information Science, Nara Institute of Science and Technology, Ikoma 630-0192, Japan"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2985-1162","authenticated-orcid":false,"given":"Akishige","family":"Yuguchi","sequence":"additional","affiliation":[{"name":"Division of Information Science, Nara Institute of Science and Technology, Ikoma 630-0192, Japan"},{"name":"Knowledge Acquisition and Dialogue Research Team, Guardian Robot Project, RIKEN, Seika-cho, Soraku-gun, Kyoto 619-0228, Japan"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5022-9936","authenticated-orcid":false,"given":"Sung-Gwi","family":"Cho","sequence":"additional","affiliation":[{"name":"Division of Information Science, Nara Institute of Science and Technology, Ikoma 630-0192, Japan"},{"name":"Division of Electronic Engineering, School of Science and Engineering, Tokyo Denki University, Hatoyama-machi, Hiki-gun, Saitama 350-0394, Japan"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4919-5772","authenticated-orcid":false,"given":"Ming","family":"Ding","sequence":"additional","affiliation":[{"name":"Division of Information Science, Nara Institute of Science and Technology, Ikoma 630-0192, Japan"},{"name":"Institutes of Innovation for Future Society, Nagoya University, Nagoya 464-8601, Japan"}]},{"given":"Sakiko","family":"Yoshikawa","sequence":"additional","affiliation":[{"name":"Faculty of Art and Design, Kyoto University of the Arts, Kyoto 606-8271, Japan"}]},{"given":"Tsukasa","family":"Ogasawara","sequence":"additional","affiliation":[{"name":"Division of Information Science, Nara Institute of Science and Technology, Ikoma 630-0192, Japan"}]}],"member":"1968","published-online":{"date-parts":[[2023,1,19]]},"reference":[{"key":"ref_1","unstructured":"Arnould-Taylor, W.E. 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