{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,31]],"date-time":"2026-03-31T07:26:24Z","timestamp":1774941984940,"version":"3.50.1"},"reference-count":57,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2021,8,5]],"date-time":"2021-08-05T00:00:00Z","timestamp":1628121600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100002661","name":"Fonds De La Recherche Scientifique - FNRS","doi-asserted-by":"publisher","award":["\/"],"award-info":[{"award-number":["\/"]}],"id":[{"id":"10.13039\/501100002661","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Cells"],"abstract":"<jats:p>Charles Bonnet syndrome (CBS) is a rare clinical condition characterized by complex visual hallucinations in people with loss of vision. So far, the neurobiological mechanisms underlying the hallucinations remain elusive. This case-report study aims at investigating electrical activity changes in a CBS patient during visual hallucinations, as compared to a resting-state period (without hallucinations). Prior to the EEG, the patient underwent neuropsychological, ophthalmologic, and neurological examinations. Spectral and connectivity, graph analyses and signal diversity were applied to high-density EEG data. Visual hallucinations (as compared to resting-state) were characterized by a significant reduction of power in the frontal areas, paralleled by an increase in the midline posterior regions in delta and theta bands and by an increase of alpha power in the occipital and midline posterior regions. We next observed a reduction of theta connectivity in the frontal and right posterior areas, which at a network level was complemented by a disruption of small-worldness (lower local and global efficiency) and by an increase of network modularity. Finally, we found a higher signal complexity especially when considering the frontal areas in the alpha band. The emergence of hallucinations may stem from these changes in the visual cortex and in core cortical regions encompassing both the default mode and the fronto-parietal attentional networks.<\/jats:p>","DOI":"10.3390\/cells10081991","type":"journal-article","created":{"date-parts":[[2021,8,5]],"date-time":"2021-08-05T09:35:32Z","timestamp":1628156132000},"page":"1991","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["High-Density EEG in a Charles Bonnet Syndrome Patient during and without Visual Hallucinations: A Case-Report Study"],"prefix":"10.3390","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4516-2671","authenticated-orcid":false,"given":"Andrea","family":"Piarulli","sequence":"first","affiliation":[{"name":"Department of Surgical, Medical, Molecular Pathology and Critical Care Medicine, University of Pisa, 56126 Pisa, Italy"},{"name":"Coma Science Group, GIGA-Consciousness, University of Li\u00e8ge, 4000 Li\u00e8ge, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jitka","family":"Annen","sequence":"additional","affiliation":[{"name":"Coma Science Group, GIGA-Consciousness, University of Li\u00e8ge, 4000 Li\u00e8ge, Belgium"},{"name":"Centre du Cerveau, University Hospital of Li\u00e8ge, 4000 Li\u00e8ge, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ron","family":"Kupers","sequence":"additional","affiliation":[{"name":"Department of Neuroscience, University of Copenhagen, 1050 Copenhagen, Denmark"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Steven","family":"Laureys","sequence":"additional","affiliation":[{"name":"Coma Science Group, GIGA-Consciousness, University of Li\u00e8ge, 4000 Li\u00e8ge, Belgium"},{"name":"Centre du Cerveau, University Hospital of Li\u00e8ge, 4000 Li\u00e8ge, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6291-3460","authenticated-orcid":false,"given":"Charlotte","family":"Martial","sequence":"additional","affiliation":[{"name":"Coma Science Group, GIGA-Consciousness, University of Li\u00e8ge, 4000 Li\u00e8ge, Belgium"},{"name":"Centre du Cerveau, University Hospital of Li\u00e8ge, 4000 Li\u00e8ge, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,8,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"254","DOI":"10.1192\/bjp.166.2.254","article-title":"The Charles Bonnet syndrome: A large prospective study in the Netherlands","volume":"166","author":"Teunisse","year":"1995","journal-title":"Br. 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