{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,2]],"date-time":"2026-01-02T12:54:50Z","timestamp":1767358490672,"version":"3.48.0"},"reference-count":33,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2025,12,26]],"date-time":"2025-12-26T00:00:00Z","timestamp":1766707200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100023652","name":"University of Rijeka, Croatia","doi-asserted-by":"crossref","award":["UNIRi-iskusni-biomed-23-145"],"award-info":[{"award-number":["UNIRi-iskusni-biomed-23-145"]}],"id":[{"id":"10.13039\/501100023652","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Neurology International"],"abstract":"<jats:p>Background\/Objectives: Beyond respiratory problems, COVID-19 can cause a variety of symptoms, such as neurological disorders caused by biological and psychological factors. Brain fog (BF), a post-illness cognitive impairment that many patients report, can be evaluated with reaction time (RT) testing. Response latency is measured by RT, which can be either simple (sRT) or complex (cRT). This study focuses on how COVID-19 affects cognitive function, with particular attention on RT changes, BF prevalence, and implications for daily life. Methods: The study included 599 participants from Bosnia and Herzegovina, Croatia and Serbia. RT was measured using PsyToolkit and participants completed a COVID-19-associated BF questionnaire. Participants who experienced BF after their latest COVID-19 infection rated its severity using a visual analogue scale (VAS). Additional clinical data were obtained from medical records. Results: BF was reported by 40% of participants post-COVID-19. Men reported it less frequently but found it more disruptive. RT progressively declined post-infection, reaching peak impairment at 15 weeks, following recovery, with RT normalizing by six months. Conclusions: COVID-19 is linked to temporary RT impairment, peaking at 15 weeks post-infection and resolving by six months, independent of BF presence. This study emphasizes the need for a biopsychosocial approach to BF management. Easily available RT assessments should be incorporated into routine clinical practice.<\/jats:p>","DOI":"10.3390\/neurolint18010006","type":"journal-article","created":{"date-parts":[[2025,12,29]],"date-time":"2025-12-29T07:52:59Z","timestamp":1766994779000},"page":"6","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Long-Term Health Consequences of SARS-CoV-2: Reaction Time and Brain Fog"],"prefix":"10.3390","volume":"18","author":[{"given":"Ana","family":"Lesac Brizi\u0107","sequence":"first","affiliation":[{"name":"Faculty of Medicine, University of Rijeka, 51000 Rijeka, Croatia"},{"name":"Health Center of Primorje-Gorski Kotar County, 51000 Rijeka, Croatia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Branislava","family":"Popovi\u0107","sequence":"additional","affiliation":[{"name":"Faculty of Medicine, University of Rijeka, 51000 Rijeka, Croatia"},{"name":"Family Medicine Office Branislava Popovi\u0107, 51000 Rijeka, Croatia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tina","family":"Zavidi\u0107","sequence":"additional","affiliation":[{"name":"Faculty of Medicine, University of Rijeka, 51000 Rijeka, Croatia"},{"name":"Istrian Health Centers, 52426 Lupoglav, Croatia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3973-5154","authenticated-orcid":false,"given":"Nevena","family":"Todorovi\u0107","sequence":"additional","affiliation":[{"name":"Family Medicine Department, Faculty of Medicine, University of Banja Luka, 78000 Banja Luka, Bosnia and Herzegovina"},{"name":"Family Medicine Teaching Centre, Primary Health Care Centre Banja Luka, 78000 Banja Luka, Bosnia and Herzegovina"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Verica","family":"Petrovi\u0107","sequence":"additional","affiliation":[{"name":"Family Medicine Department, Faculty of Medicine, University of Banja Luka, 78000 Banja Luka, Bosnia and Herzegovina"},{"name":"Family Medicine Teaching Centre, Primary Health Care Centre Banja Luka, 78000 Banja Luka, Bosnia and Herzegovina"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5038-1978","authenticated-orcid":false,"given":"Nata\u0161a","family":"Pilipovi\u0107-Bro\u0107eta","sequence":"additional","affiliation":[{"name":"Family Medicine Department, Faculty of Medicine, University of Banja Luka, 78000 Banja Luka, Bosnia and Herzegovina"},{"name":"Family Medicine Teaching Centre, Primary Health Care Centre Banja Luka, 78000 Banja Luka, Bosnia and Herzegovina"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6540-5349","authenticated-orcid":false,"given":"Ana R.","family":"Miljkovi\u0107","sequence":"additional","affiliation":[{"name":"The Medical Faculty in Novi Sad, University of Novi Sad, 21000 Novi Sad, Serbia"},{"name":"Community Health Centre Novi Sad, 21000 Novi Sad, Serbia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Aleksandar","family":"Ljubotina","sequence":"additional","affiliation":[{"name":"Faculty of Medicine, University of Rijeka, 51000 Rijeka, Croatia"},{"name":"Family Medicine Office Aleksandar Ljubotina, 51000 Rijeka, Croatia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0873-1257","authenticated-orcid":false,"given":"Ema","family":"Dejhalla","sequence":"additional","affiliation":[{"name":"Faculty of Medicine, University of Rijeka, 51000 Rijeka, Croatia"},{"name":"Medical Centre for Occupational Health Rijeka, 51000 Rijeka, Croatia"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,12,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"283","DOI":"10.1006\/phrs.1999.0585","article-title":"Protective effect of thymoquinone against doxorubicin-induced cardiotoxicity in rats: A possible mechanism of protection","volume":"41","author":"Nagi","year":"2000","journal-title":"Pharmacol. 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