{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T01:24:27Z","timestamp":1760145867843,"version":"build-2065373602"},"reference-count":42,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2024,9,13]],"date-time":"2024-09-13T00:00:00Z","timestamp":1726185600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"ConsciousBrainConcepts project under the Life Science Convergence Projects initiative of the University of Oslo and the European Union\u2019s Horizon 2020 Framework Programme for Research and Innovation","award":["945539","785907","262950\/F20","FRIPRO 335828"],"award-info":[{"award-number":["945539","785907","262950\/F20","FRIPRO 335828"]}]},{"DOI":"10.13039\/501100005416","name":"Norwegian Research Council","doi-asserted-by":"publisher","award":["945539","785907","262950\/F20","FRIPRO 335828"],"award-info":[{"award-number":["945539","785907","262950\/F20","FRIPRO 335828"]}],"id":[{"id":"10.13039\/501100005416","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Brain Sciences"],"abstract":"<jats:p>Background: Developing and testing methods for reliably measuring the state of consciousness of individuals is important for both basic research and clinical purposes. In recent years, several promising measures of consciousness, grounded in theoretical developments, have been proposed. However, the degrees to which these measures are affected by changes in brain activity that are not related to changes in the degree of consciousness has not been well tested. In this study, we examined whether several of these measures are modulated by the loading of cognitive resources. Methods: We recorded electroencephalography (EEG) from 12 participants in two conditions: (1) while passively attending to sensory stimuli related to the measures and (2) during increased cognitive load consisting of a demanding working memory task. We investigated whether a set of proposed objective EEG-based measures of consciousness differed between the passive and the cognitively demanding conditions. Results: The P300b event-related potential (sensitive to conscious awareness of deviance from an expected pattern in auditory stimuli) was significantly affected by concurrent performance on a working memory task, whereas various measures based on signal diversity of spontaneous and perturbed EEG were not. Conclusion: Because signal diversity-based measures of spontaneous or perturbed EEG are not sensitive to the degree of cognitive load, we suggest that these measures may be used in clinical situations where attention, sensory processing, or command following might be impaired.<\/jats:p>","DOI":"10.3390\/brainsci14090919","type":"journal-article","created":{"date-parts":[[2024,9,13]],"date-time":"2024-09-13T10:02:54Z","timestamp":1726221774000},"page":"919","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Does Cognitive Load Affect Measures of Consciousness?"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2084-6663","authenticated-orcid":false,"given":"Andr\u00e9 Sevenius","family":"Nilsen","sequence":"first","affiliation":[{"name":"Brain Signaling Group, Department of Physiology, Institute of Basic Medical Sciences, University of Oslo, 0372 Oslo, Norway"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Johan Frederik","family":"Storm","sequence":"additional","affiliation":[{"name":"Brain Signaling Group, Department of Physiology, Institute of Basic Medical Sciences, University of Oslo, 0372 Oslo, Norway"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0550-581X","authenticated-orcid":false,"given":"Bj\u00f8rn Erik","family":"Juel","sequence":"additional","affiliation":[{"name":"Vestre Viken Klinisk Nevrofysiologi, Kongsberg Hospital, Vestre Viken Health Trust, 3004 Drammen, Norway"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2024,9,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1138","DOI":"10.1016\/S0140-6736(89)92415-X","article-title":"Coma Scale to Predict Survival","volume":"1","author":"Benzer","year":"1989","journal-title":"Lancet"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"11096","DOI":"10.1073\/pnas.0903941106","article-title":"Baseline Brain Energy Supports the State of Consciousness","volume":"106","author":"Shulman","year":"2009","journal-title":"Proc. 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