{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,30]],"date-time":"2026-04-30T01:30:40Z","timestamp":1777512640211,"version":"3.51.4"},"reference-count":29,"publisher":"MDPI AG","issue":"22","license":[{"start":{"date-parts":[[2020,11,12]],"date-time":"2020-11-12T00:00:00Z","timestamp":1605139200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Vingroup Innovation Foundation (VINIF) in project code","award":["VINIF.2019.DA14"],"award-info":[{"award-number":["VINIF.2019.DA14"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJERPH"],"abstract":"<jats:p>Background: There is little understanding on how brief relaxation practice and viewing greenery images would affect brain responses during cognitive tasks. In the present study, we examined the variation in brain activation of the prefrontal cortex during arithmetic tasks before and after viewing greenery images, brief relaxation practice, and control task using functional near-infrared spectroscopy (fNIRS). Method: This randomized controlled study examined the activation patterns of the prefrontal cortex (PFC) in three groups of research participants who were exposed to viewing greenery images (n = 10), brief relaxation practice (n = 10), and control task (n = 11). The activation pattern of the PFC was measured pre- and post-intervention using a portable fNIRS device and reported as mean total oxygenated hemoglobin (HbO \u03bcm). Primary outcome of the study is the difference in HbO \u03bcm between post- and pre-intervention readings during a cognitive task that required the research participants to perform arithmetic calculation. Results: In terms of intervention-related differences, there was significant difference in average HbO \u03bcm when performing arithmetic tasks before and after brief relaxation practice (p &lt; 0.05). There were significant increases in average HbO \u03bcm in the right frontopolar cortex (p = 0.029), the left frontopolar cortex (p = 0.01), and the left orbitofrontal cortex (p = 0.033) during arithmetic tasks after brief relaxation practice. In contrast, there were no significant differences in average HbO \u03bcm when performing arithmetic tasks before and after viewing greenery images (p &gt; 0.05) and the control task (p &gt; 0.05). Conclusion: Our preliminary findings show that brief relaxation practice but not viewing greenery images led to significant frontal lobe activation during arithmetic tasks. The present study demonstrated, for the first time, that there was an increase in activation in neuroanatomical areas including the combined effort of allocation of attentional resources, exploration, and memory performance after the brief relaxation practice. Our findings suggest the possibility that the right frontopolar cortex, the left frontopolar cortex, and the left orbitofrontal cortex may be specifically associated with the benefits of brief relaxation on the brain.<\/jats:p>","DOI":"10.3390\/ijerph17228366","type":"journal-article","created":{"date-parts":[[2020,11,12]],"date-time":"2020-11-12T10:00:32Z","timestamp":1605175232000},"page":"8366","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":23,"title":["Brief Relaxation Practice Induces Significantly More Prefrontal Cortex Activation during Arithmetic Tasks Comparing to Viewing Greenery Images as Revealed by Functional Near-Infrared Spectroscopy (fNIRS)"],"prefix":"10.3390","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3680-8701","authenticated-orcid":false,"given":"Zhisong","family":"Zhang","sequence":"first","affiliation":[{"name":"Faculty of Education, Huaibei Normal University, Huaibei 117599, China"},{"name":"Institute for Health Innovation and Technology (iHealthtech), National University of Singapore, Singapore 117599, Singapore"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5278-0374","authenticated-orcid":false,"given":"Agnieszka","family":"Olszewska-Guizzo","sequence":"additional","affiliation":[{"name":"Institute for Health Innovation and Technology (iHealthtech), National University of Singapore, Singapore 117599, Singapore"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7460-397X","authenticated-orcid":false,"given":"Syeda Fabeha","family":"Husain","sequence":"additional","affiliation":[{"name":"Institute for Health Innovation and Technology (iHealthtech), National University of Singapore, Singapore 117599, Singapore"},{"name":"Department of Psychological Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119228, Singapore"}]},{"given":"Jessica","family":"Bose","sequence":"additional","affiliation":[{"name":"Department of Psychological Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119228, Singapore"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2159-9246","authenticated-orcid":false,"given":"Jongkwan","family":"Choi","sequence":"additional","affiliation":[{"name":"OBELAB, Inc., Seoul 06212, Korea"}]},{"given":"Wanqiu","family":"Tan","sequence":"additional","affiliation":[{"name":"National University of Singapore (Chongqing) Research Institute, Chongqing 401123, China"}]},{"given":"Jiayun","family":"Wang","sequence":"additional","affiliation":[{"name":"Faculty of Education, Huaibei Normal University, Huaibei 117599, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7827-8449","authenticated-orcid":false,"given":"Bach","family":"Xuan Tran","sequence":"additional","affiliation":[{"name":"Institute for Preventive Medicine and Public Health, Hanoi Medical University, Hanoi 100000, Vietnam"},{"name":"Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, MD 21205, USA"}]},{"given":"Bokun","family":"Wang","sequence":"additional","affiliation":[{"name":"Science and Technology Promotion Bureau, Chongqing Liangjiang New Area Administration Committee, Chongqing 201205, China"}]},{"given":"Yajie","family":"Jin","sequence":"additional","affiliation":[{"name":"Faculty of Education, Huaibei Normal University, Huaibei 117599, China"}]},{"given":"Wei","family":"Xuan","sequence":"additional","affiliation":[{"name":"Faculty of Education, Huaibei Normal University, Huaibei 117599, China"}]},{"given":"Pinjia","family":"Yan","sequence":"additional","affiliation":[{"name":"Faculty of Education, Huaibei Normal University, Huaibei 117599, China"}]},{"given":"Maomao","family":"Li","sequence":"additional","affiliation":[{"name":"Faculty of Education, Huaibei Normal University, Huaibei 117599, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7092-9566","authenticated-orcid":false,"given":"Cyrus S. H.","family":"Ho","sequence":"additional","affiliation":[{"name":"Department of Psychological Medicine, National University Hospital, Singapore 119074, Singapore"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9629-4493","authenticated-orcid":false,"given":"Roger","family":"Ho","sequence":"additional","affiliation":[{"name":"Faculty of Education, Huaibei Normal University, Huaibei 117599, China"},{"name":"Institute for Health Innovation and Technology (iHealthtech), National University of Singapore, Singapore 117599, Singapore"},{"name":"Department of Psychological Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119228, Singapore"}]}],"member":"1968","published-online":{"date-parts":[[2020,11,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"15860","DOI":"10.3390\/ijerph121215026","article-title":"Autonomic nervous system responses to viewing green and built settings: Differentiating between sympathetic and parasympathetic activity","volume":"12","author":"Maas","year":"2015","journal-title":"Int. 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