{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,1]],"date-time":"2026-04-01T17:53:20Z","timestamp":1775066000256,"version":"3.50.1"},"reference-count":45,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2021,9,11]],"date-time":"2021-09-11T00:00:00Z","timestamp":1631318400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003196","name":"Ministero della Salute","doi-asserted-by":"publisher","award":["2011-02348998"],"award-info":[{"award-number":["2011-02348998"]}],"id":[{"id":"10.13039\/501100003196","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100007514","name":"Universit\u00e0 di Pisa","doi-asserted-by":"publisher","award":["Ateneo 2019"],"award-info":[{"award-number":["Ateneo 2019"]}],"id":[{"id":"10.13039\/501100007514","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Symmetry"],"abstract":"<jats:p>In humans, the asymmetry in the masseter electromyographic (EMG) activity during clenching is positively correlated with the degree of pupil size asymmetry (anisocoria) at rest. Anisocoria reveals an asymmetry in LC activity, which may lead to an imbalance in cortical excitability, detrimental to performance. Hereby, we investigated, in individual subjects, the possibility that occlusal correction, which decreases EMG asymmetry, improves performance by balancing LC activity. Cognitive performance, task-related mydriasis, and pupil size at rest were modified by changing the occlusal condition. Occlusal-related changes in performance and mydriasis were negatively correlated with anisocoria changes in only 12\/20 subjects. Within this population, spontaneous fluctuations in mydriasis and anisocoria also appeared negatively coupled. Occlusal-related changes in performance and mydriasis were negatively correlated with those in average pupil size (a proxy of average LC activity) in 19\/20 subjects. The strongest association was observed for the pupil changes occurring on the side with higher EMG activity during clenching. These findings indicate that the effects of occlusal conditions on cognitive performance were coupled to changes in the asymmetry of LC activity in about half of the subjects, while they were related to changes in the average tonic LC activity in virtually all of them.<\/jats:p>","DOI":"10.3390\/sym13091676","type":"journal-article","created":{"date-parts":[[2021,9,12]],"date-time":"2021-09-12T21:48:01Z","timestamp":1631483281000},"page":"1676","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["Coupling between Trigeminal-Induced Asymmetries in Locus Coeruleus Activity and Cognitive Performance"],"prefix":"10.3390","volume":"13","author":[{"given":"Maria Paola","family":"Tramonti Fantozzi","sequence":"first","affiliation":[{"name":"Department of Translational Research and of New Surgical and Medical Technologies, University of Pisa, 56127 Pisa, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2279-5599","authenticated-orcid":false,"given":"Ottavia","family":"Marconi","sequence":"additional","affiliation":[{"name":"Department of Surgical, Medical, Molecular Pathology and Critical Care Medicine, University of Pisa, 56124 Pisa, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Federica","family":"Simoni","sequence":"additional","affiliation":[{"name":"Department of Surgical, Medical, Molecular Pathology and Critical Care Medicine, University of Pisa, 56124 Pisa, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Vincenzo","family":"De Cicco","sequence":"additional","affiliation":[{"name":"Department of Translational Research and of New Surgical and Medical Technologies, University of Pisa, 56127 Pisa, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4363-388X","authenticated-orcid":false,"given":"Davide","family":"De Cicco","sequence":"additional","affiliation":[{"name":"Department of Neurosciences, Reproductive and Odontostomatological Sciences, University of Naples \u201cFederico II\u201d, 80138 Naples, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Enrico","family":"Cataldo","sequence":"additional","affiliation":[{"name":"Department of Physics, University of Pisa, 56127 Pisa, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Massimo","family":"Barresi","sequence":"additional","affiliation":[{"name":"Comprehensive Middle School Albano, Albano S. Alessandro, 24122 Bergamo, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6900-1306","authenticated-orcid":false,"given":"Luca","family":"Bruschini","sequence":"additional","affiliation":[{"name":"Department of Translational Research and of New Surgical and Medical Technologies, University of Pisa, 56127 Pisa, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Paola","family":"d\u2019Ascanio","sequence":"additional","affiliation":[{"name":"Department of Translational Research and of New Surgical and Medical Technologies, University of Pisa, 56127 Pisa, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ugo","family":"Faraguna","sequence":"additional","affiliation":[{"name":"Department of Translational Research and of New Surgical and Medical Technologies, University of Pisa, 56127 Pisa, Italy"},{"name":"Department of Developmental Neuroscience, IRCCS Fondazione Stella Maris, 56128 Pisa, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Diego","family":"Manzoni","sequence":"additional","affiliation":[{"name":"Department of Translational Research and of New Surgical and Medical Technologies, University of Pisa, 56127 Pisa, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,9,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1143","DOI":"10.1017\/S0952523800007781","article-title":"Removal of two halves restores the whole: Reversal of visual hemineglect during bilateral cortical or collicular inactivation in the cat","volume":"13","author":"Lomber","year":"1996","journal-title":"Vis. 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