{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,31]],"date-time":"2026-08-31T18:14:06Z","timestamp":1788200046837,"version":"build-2803163510"},"reference-count":34,"publisher":"Public Library of Science (PLoS)","issue":"8","license":[{"start":{"date-parts":[[2026,8,31]],"date-time":"2026-08-31T00:00:00Z","timestamp":1788134400000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS One"],"abstract":"<jats:p>Ramadan diurnal intermittent fasting (RDIF) represents a natural model of prolonged daily intermittent fasting associated with metabolic and circadian alterations. This study investigated longitudinal changes in intracortical excitability across pre-, mid-, and post-Ramadan timepoints in healthy adults observing RDIF. Thirty fasting participants in this prospective observational cohort study underwent paired-pulse transcranial magnetic stimulation at three timepoints (pre-, mid-, and post-Ramadan). A non-fasting control group (n\u2009=\u200911) was assessed at pre- and mid-Ramadan. Conditioned motor-evoked potentials were recorded at interstimulus intervals of 2\u201310 ms and normalized to unconditioned responses. A linear mixed-effects model assessed effects of Timepoint and interstimulus interval (ISI). Secondary outcomes included blood glucose, cognitive performance, sleep duration, and reaction time. A significant main effect of Timepoint (p\u2009&lt;\u20090.001) indicated longitudinal modulation of intracortical excitability, with increased MEP ratios at mid-Ramadan and partial persistence post-Ramadan. The ISI effect confirmed the inhibition\u2013facilitation gradient (p\u2009&lt;\u20090.001). The Timepoint\u2009\u00d7\u2009ISI interaction was not significant (p\u2009=\u20090.566), indicating a global shift in excitability without ISI-specific modulation. Blood glucose and sleep duration decreased significantly at mid-Ramadan. RDIF is associated with a time-dependent increase in intracortical excitability, most appropriately interpreted as a generalized shift rather than selective modulation of inhibitory or facilitatory circuits. These changes occur in the context of concurrent metabolic, sleep, and circadian alterations and may reflect combined physiological influences of these factors; however, their individual contributions cannot be disentangled within the present naturalistic observational design. Because the non-fasting comparison group was not evaluated after Ramadan, the persistence of elevated intracortical excitability beyond Ramadan requires confirmation in adequately controlled longitudinal studies.<\/jats:p>","DOI":"10.1371\/journal.pone.0349740","type":"journal-article","created":{"date-parts":[[2026,8,31]],"date-time":"2026-08-31T17:24:38Z","timestamp":1788197078000},"page":"e0349740","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":0,"title":["Longitudinal changes in intracortical excitability during Ramadan diurnal intermittent fasting: A paired-pulse transcranial magnetic stimulation study"],"prefix":"10.1371","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4984-2535","authenticated-orcid":true,"given":"Meeyoung","family":"Kim","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ibrahim M.","family":"Mostafa","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alham","family":"Al-Sharman","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0003-0012-2868","authenticated-orcid":true,"given":"Nabil","family":"Saad","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hanan","family":"Khalil","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hikmat","family":"Hadoush","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"340","published-online":{"date-parts":[[2026,8,31]]},"reference":[{"issue":"2","key":"pone.0349740.ref001","doi-asserted-by":"crossref","first-page":"771","DOI":"10.1007\/s11325-019-01986-1","article-title":"Effect of diurnal fasting on sleep during Ramadan: a systematic review and meta-analysis","volume":"24","author":"MA-IE Faris","year":"2020","journal-title":"Sleep Breath"},{"key":"pone.0349740.ref002","doi-asserted-by":"crossref","first-page":"2291","DOI":"10.1007\/s00394-020-02216-1","article-title":"A systematic review, meta-analysis, and meta-regression of the impact of diurnal intermittent fasting during Ramadan on body weight in healthy subjects aged 16 years and above","volume":"59","author":"HA Jahrami","year":"2020","journal-title":"Eur J Nutr"},{"issue":"3","key":"pone.0349740.ref003","doi-asserted-by":"crossref","first-page":"577","DOI":"10.1007\/s11325-017-1473-x","article-title":"The effect of intermittent fasting during Ramadan on sleep, sleepiness, cognitive function, and circadian rhythm","volume":"21","author":"SO Qasrawi","year":"2017","journal-title":"Sleep Breath"},{"key":"pone.0349740.ref004","doi-asserted-by":"crossref","first-page":"28","DOI":"10.3389\/fnut.2020.00028","article-title":"Recent evidence on the impact of Ramadan diurnal intermittent fasting, mealtime, and circadian rhythm on cardiometabolic risk: a review","volume":"7","author":"AS BaHammam","year":"2020","journal-title":"Front Nutr"},{"key":"pone.0349740.ref005","doi-asserted-by":"crossref","first-page":"439","DOI":"10.2147\/NSS.S165637","article-title":"How does diurnal intermittent fasting impact sleep, daytime sleepiness, and markers of the biological clock?","volume":"10","author":"AS Almeneessier","year":"2018","journal-title":"Nat Sci Sleep"},{"issue":"2","key":"pone.0349740.ref006","article-title":"Chrononutrition in the context of Ramadan: potential implications","volume":"40","author":"T Ali","year":"2024","journal-title":"Diabetes Metab Res Rev"},{"issue":"1","key":"pone.0349740.ref007","doi-asserted-by":"crossref","first-page":"54","DOI":"10.1093\/ajcn\/nqx016","article-title":"The effects of Ramadan fasting on activity and energy expenditure","volume":"107","author":"N Lessan","year":"2018","journal-title":"Am J Clin Nutr"},{"key":"pone.0349740.ref008","doi-asserted-by":"crossref","first-page":"1192","DOI":"10.3390\/nu11051192","article-title":"Energy metabolism and intermittent fasting: the Ramadan perspective","volume":"11","author":"N Lessan","year":"2019","journal-title":"Nutrients"},{"issue":"12","key":"pone.0349740.ref009","doi-asserted-by":"crossref","first-page":"339","DOI":"10.3390\/brainsci9120339","article-title":"The impact of glucose on corticospinal and intracortical excitability","volume":"9","author":"SL Toepp","year":"2019","journal-title":"Brain Sci"},{"key":"pone.0349740.ref010","doi-asserted-by":"crossref","first-page":"11828","DOI":"10.1038\/ncomms11828","article-title":"Circadian regulation of human cortical excitability","volume":"7","author":"JQM Ly","year":"2016","journal-title":"Nat Commun"},{"issue":"10","key":"pone.0349740.ref011","doi-asserted-by":"crossref","first-page":"2299","DOI":"10.1093\/cercor\/bhr003","article-title":"Circadian modulation of GABA-mediated cortical inhibition","volume":"21","author":"N Lang","year":"2011","journal-title":"Cereb Cortex"},{"issue":"6","key":"pone.0349740.ref012","doi-asserted-by":"crossref","first-page":"1071","DOI":"10.1016\/j.clinph.2015.02.001","article-title":"Non-invasive electrical and magnetic stimulation of the brain, spinal cord, roots and peripheral nerves: basic principles and procedures for routine clinical and research application. An updated report from an I.F.C.N. Committee","volume":"126","author":"PM Rossini","year":"2015","journal-title":"Clin Neurophysiol"},{"key":"pone.0349740.ref013","doi-asserted-by":"crossref","first-page":"501","DOI":"10.1113\/jphysiol.1993.sp019912","article-title":"Corticocortical inhibition in human motor cortex","volume":"471","author":"T Kujirai","year":"1993","journal-title":"J Physiol"},{"key":"pone.0349740.ref014","doi-asserted-by":"crossref","first-page":"661","DOI":"10.1113\/jphysiol.2004.061747","article-title":"Effects of lorazepam on short latency afferent inhibition and short latency intracortical inhibition in humans","volume":"564","author":"V Di Lazzaro","year":"2005","journal-title":"J Physiol"},{"issue":"1","key":"pone.0349740.ref015","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1007\/s00221-003-1684-1","article-title":"Interactions between inhibitory and excitatory circuits in the human motor cortex","volume":"154","author":"R Chen","year":"2004","journal-title":"Exp Brain Res"},{"key":"pone.0349740.ref016","doi-asserted-by":"crossref","first-page":"1298281","DOI":"10.3389\/fnut.2024.1298281","article-title":"Alterations in anthropometric, inflammatory and mental health parameters during Ramadan intermittent fasting in a group of healthy people: a prospective cohort study","volume":"11","author":"SK Ghashang","year":"2024","journal-title":"Front Nutr"},{"issue":"9596","key":"pone.0349740.ref017","doi-asserted-by":"crossref","first-page":"1453","DOI":"10.1016\/S0140-6736(07)61602-X","article-title":"The Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) statement: guidelines for reporting observational studies","volume":"370","author":"E von Elm","year":"2007","journal-title":"Lancet"},{"key":"pone.0349740.ref018","doi-asserted-by":"crossref","first-page":"873","DOI":"10.1113\/jphysiol.1996.sp021734","article-title":"Interaction between intracortical inhibition and facilitation in human motor cortex","author":"U Ziemann","year":"1996","journal-title":"J Physiol"},{"key":"pone.0349740.ref019","doi-asserted-by":"crossref","first-page":"1304221","DOI":"10.3389\/fnhum.2024.1304221","article-title":"Episodic memory assessment: effects of sex and age on performance and response time during a continuous recognition task","volume":"18","author":"JO Clifford","year":"2024","journal-title":"Front Hum Neurosci"},{"key":"pone.0349740.ref020","doi-asserted-by":"crossref","first-page":"99","DOI":"10.1093\/arclin\/acaa034","article-title":"Construct validity of the stroop color-word test: influence of speed of visual search, verbal fluency, working memory, cognitive flexibility, and conflict monitoring","volume":"36","author":"JA Peri\u00e1\u00f1ez","year":"2021","journal-title":"Arch Clin Neuropsychol"},{"issue":"4","key":"pone.0349740.ref021","doi-asserted-by":"crossref","first-page":"327","DOI":"10.4085\/1062-6050-45.4.327","article-title":"Pilot evaluation of a novel clinical test of reaction time in national collegiate athletic association division I football players","volume":"45","author":"JT Eckner","year":"2010","journal-title":"J Athl Train"},{"key":"pone.0349740.ref022","doi-asserted-by":"crossref","first-page":"1717","DOI":"10.1016\/j.clinph.2004.03.006","article-title":"TMS and drugs","volume":"115","author":"U Ziemann","year":"2004","journal-title":"Clin Neurophysiol"},{"issue":"2","key":"pone.0349740.ref023","doi-asserted-by":"crossref","first-page":"113","DOI":"10.1016\/S0165-0270(97)02242-5","article-title":"Techniques and mechanisms of action of transcranial stimulation of the human motor cortex","volume":"74","author":"JC Rothwell","year":"1997","journal-title":"J Neurosci Methods"},{"issue":"2","key":"pone.0349740.ref024","doi-asserted-by":"crossref","first-page":"265","DOI":"10.1016\/j.jneumeth.2007.06.002","article-title":"A comparative study of the effects of repetitive paired transcranial magnetic stimulation on motor cortical excitability","volume":"165","author":"PB Fitzgerald","year":"2007","journal-title":"J Neurosci Methods"},{"key":"pone.0349740.ref025","doi-asserted-by":"crossref","first-page":"46","DOI":"10.1016\/j.arr.2016.10.005","article-title":"Impact of intermittent fasting on health and disease processes","volume":"39","author":"MP Mattson","year":"2017","journal-title":"Ageing Res Rev"},{"issue":"4","key":"pone.0349740.ref026","article-title":"Ramadan fasting in Saudi Arabia is associated with altered expression of CLOCK, DUSP and IL-1alpha genes, as well as changes in cardiometabolic risk factors","volume":"12","author":"GMA Ajabnoor","year":"2017","journal-title":"PLoS One"},{"key":"pone.0349740.ref027","doi-asserted-by":"crossref","first-page":"18","DOI":"10.1016\/j.jnim.2018.11.005","article-title":"Impact of diurnal intermittent fasting during Ramadan on inflammatory and oxidative stress markers in healthy people: systematic review and meta-analysis","volume":"15","author":"MA-IE Faris","year":"2019","journal-title":"J Nutr Intermed Metab"},{"key":"pone.0349740.ref028","doi-asserted-by":"crossref","first-page":"5163","DOI":"10.1113\/jphysiol.2009.179820","article-title":"Interactions between short-interval intracortical inhibition and short-latency afferent inhibition in human motor cortex","volume":"587","author":"H Alle","year":"2009","journal-title":"J Physiol"},{"issue":"1","key":"pone.0349740.ref029","article-title":"Intermittent fasting increases adult hippocampal neurogenesis","volume":"10","author":"S-H Baik","year":"2020","journal-title":"Brain Behav"},{"key":"pone.0349740.ref030","doi-asserted-by":"crossref","first-page":"100971","DOI":"10.1016\/j.yfrne.2021.100971","article-title":"Intermittent fasting and cognitive performance - Targeting BDNF as potential strategy to optimise brain health","volume":"65","author":"K Seidler","year":"2022","journal-title":"Front Neuroendocrinol"},{"key":"pone.0349740.ref031","doi-asserted-by":"crossref","first-page":"909614","DOI":"10.3389\/fnagi.2022.909614","article-title":"Practice effect of repeated cognitive tests among older adults: associations with brain amyloid pathology and other influencing factors","volume":"14","author":"B Zheng","year":"2022","journal-title":"Front Aging Neurosci"},{"issue":"1","key":"pone.0349740.ref032","doi-asserted-by":"crossref","first-page":"32","DOI":"10.1186\/1744-9081-9-32","article-title":"Objective assessment of drowsiness and reaction time during intermittent Ramadan fasting in young men: a case-crossover study","volume":"9","author":"AS Bahammam","year":"2013","journal-title":"Behav Brain Funct"},{"issue":"8","key":"pone.0349740.ref033","doi-asserted-by":"crossref","DOI":"10.1371\/journal.pone.0136081","article-title":"The effects of sex hormonal fluctuations during menstrual cycle on cortical excitability and manual dexterity (a pilot study)","volume":"10","author":"M Zoghi","year":"2015","journal-title":"PLoS One"},{"issue":"6","key":"pone.0349740.ref034","doi-asserted-by":"crossref","first-page":"1701","DOI":"10.1152\/japplphysiol.01041.2018","article-title":"Menstrual cycle-associated modulations in neuromuscular function and fatigability of the knee extensors in eumenorrheic women","volume":"126","author":"P Ansdell","year":"2019","journal-title":"J Appl Physiol (1985)"}],"container-title":["PLOS One"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/dx.plos.org\/10.1371\/journal.pone.0349740","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,8,31]],"date-time":"2026-08-31T17:24:45Z","timestamp":1788197085000},"score":1,"resource":{"primary":{"URL":"https:\/\/dx.plos.org\/10.1371\/journal.pone.0349740"}},"subtitle":[],"editor":[{"given":"MoezAlIslam","family":"Faris","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"editor"}]}],"short-title":[],"issued":{"date-parts":[[2026,8,31]]},"references-count":34,"journal-issue":{"issue":"8","published-online":{"date-parts":[[2026,8,31]]}},"URL":"https:\/\/doi.org\/10.1371\/journal.pone.0349740","relation":{},"ISSN":["1932-6203"],"issn-type":[{"value":"1932-6203","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,8,31]]}}}