{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,17]],"date-time":"2025-11-17T10:59:40Z","timestamp":1763377180457,"version":"3.45.0"},"reference-count":39,"publisher":"MDPI AG","issue":"22","license":[{"start":{"date-parts":[[2025,11,16]],"date-time":"2025-11-16T00:00:00Z","timestamp":1763251200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Applied Sciences"],"abstract":"<jats:p>Post-occlusive reactive hyperemia (PORH) is widely used to assess microvascular reactivity, but its systemic impact on contralateral neurovascular function remains unclear. This study quantified bilateral synchrony and asymmetry of cutaneous signals during unilateral PORH in healthy subjects using a novel multidimensional framework of inter-limb coherence. Twelve young adults underwent a standard suprasystolic occlusion (5 min at 200 mmHg) on the upper limb, while photoplethysmography (PPG), skin temperature, and electrodermal activity (EDA) were recorded bilaterally in the fingers. Coherence was characterized by profile similarity (Cross-Signal Similarity Index, CSSI), temporal lag (\u03c4*), magnitude asymmetry (Bilateral Magnitude Difference Index, BDMI), directional concordance (Signal Direction Index, SDI; Directional Concordance Index, DCI), and integrated indices (IBIL, IBIS). At baseline, all signals showed high bilateral synchrony (CSSI \u2248 0.9; \u03c4* &lt; 20 ms). Occlusion markedly reduced CSSI for blood flow (0.89 to 0.07, p = 0.002) and temperature (0.93 to \u22120.03, p = 0.06), while EDA coherence remained preserved (0.95 to 0.82). Integrated indices decreased significantly (IBIL 0.84 to 0.17, p = 0.005; IBIS 0.84 to 0.18, p = 0.004) and recovered only partially during hyperemia (IBIL 0.20, p = 0.003). Directional concordance was heterogeneous: during hyperemia, 9 of 12 subjects showed concordant EDA changes but only 7 of 12 for perfusion. BDMI was largest for perfusion (\u22480.8), moderate for temperature (\u22480.5), and minimal for EDA (\u22480.3). Unilateral PORH thus induces a marked loss of bilateral coherence in microvascular signals, whereas sympathetic-driven responses remain strongly synchronized. This dissociation reveals that occlusion evokes systemic autonomic adjustments beyond local hemodynamics. The proposed framework captures hidden aspects of neurovascular integration and may provide new markers for autonomic imbalance or perfusion asymmetry.<\/jats:p>","DOI":"10.3390\/app152212142","type":"journal-article","created":{"date-parts":[[2025,11,17]],"date-time":"2025-11-17T10:24:58Z","timestamp":1763375098000},"page":"12142","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Quantifying Bilateral Synchrony and Asymmetry of Neurovascular Responses to Post-Occlusive Reactive Hyperemia"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3258-5851","authenticated-orcid":false,"given":"Henrique","family":"Silva","sequence":"first","affiliation":[{"name":"Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de Lisboa, Av. Prof. Gama Pinto, 1649-003 Lisbon, Portugal"},{"name":"Department of Pharmacy, Pharmacology and Health Technologies, Faculty of Pharmacy, Universidade de Lisboa, Av. Prof. Gama Pinto, 1649-003 Lisbon, Portugal"},{"name":"Biophysics and Biomedical Engineering Institute (IBEB), Faculty of Sciences, Universidade de Lisboa, Campo Grande, 1749-016 Lisbon, Portugal"}]},{"given":"Nicole","family":"Lavrador","sequence":"additional","affiliation":[{"name":"Department of Pharmacy, Pharmacology and Health Technologies, Faculty of Pharmacy, Universidade de Lisboa, Av. Prof. Gama Pinto, 1649-003 Lisbon, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4323-3942","authenticated-orcid":false,"given":"Hugo Alexandre","family":"Ferreira","sequence":"additional","affiliation":[{"name":"Biophysics and Biomedical Engineering Institute (IBEB), Faculty of Sciences, Universidade de Lisboa, Campo Grande, 1749-016 Lisbon, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2025,11,16]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"e55316","DOI":"10.7554\/eLife.55316","article-title":"Deciphering the neural signature of human cardiovascular regulation","volume":"9","author":"Manuel","year":"2020","journal-title":"eLife"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"204","DOI":"10.4330\/wjc.v7.i4.204","article-title":"Autonomic and endocrine control of cardiovascular function","volume":"7","author":"Gordan","year":"2015","journal-title":"World J. 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