{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,9]],"date-time":"2026-04-09T15:12:06Z","timestamp":1775747526618,"version":"3.50.1"},"reference-count":47,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2018,1,9]],"date-time":"2018-01-09T00:00:00Z","timestamp":1515456000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>The discrimination of early Alzheimer\u2019s disease (AD) and its prodromal form (i.e., mild cognitive impairment, MCI) from cognitively healthy control (HC) subjects is crucial since the treatment is more effective in the first stages of the dementia. The aim of our study is to evaluate the usefulness of a methodology based on electroencephalography (EEG) to detect AD and MCI. EEG rhythms were recorded from 37 AD patients, 37 MCI subjects and 37 HC subjects. Artifact-free trials were analyzed by means of several spectral and nonlinear features: relative power in the conventional frequency bands, median frequency, individual alpha frequency, spectral entropy, Lempel\u2013Ziv complexity, central tendency measure, sample entropy, fuzzy entropy, and auto-mutual information. Relevance and redundancy analyses were also conducted through the fast correlation-based filter (FCBF) to derive an optimal set of them. The selected features were used to train three different models aimed at classifying the trials: linear discriminant analysis (LDA), quadratic discriminant analysis (QDA) and multi-layer perceptron artificial neural network (MLP). Afterwards, each subject was automatically allocated in a particular group by applying a trial-based majority vote procedure. After feature extraction, the FCBF method selected the optimal set of features: individual alpha frequency, relative power at delta frequency band, and sample entropy. Using the aforementioned set of features, MLP showed the highest diagnostic performance in determining whether a subject is not healthy (sensitivity of 82.35% and positive predictive value of 84.85% for HC vs. all classification task) and whether a subject does not suffer from AD (specificity of 79.41% and negative predictive value of 84.38% for AD vs. all comparison). Our findings suggest that our methodology can help physicians to discriminate AD, MCI and HC.<\/jats:p>","DOI":"10.3390\/e20010035","type":"journal-article","created":{"date-parts":[[2018,1,9]],"date-time":"2018-01-09T14:00:08Z","timestamp":1515506408000},"page":"35","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":126,"title":["Automated Multiclass Classification of Spontaneous EEG Activity in Alzheimer\u2019s Disease and Mild Cognitive Impairment"],"prefix":"10.3390","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1483-2265","authenticated-orcid":false,"given":"Sa\u00fal","family":"Ruiz-G\u00f3mez","sequence":"first","affiliation":[{"name":"Biomedical Engineering Group, E.T.S.I. de Telecomunicaci\u00f3n, Universidad de Valladolid, 47011 Valladolid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9488-0605","authenticated-orcid":false,"given":"Carlos","family":"G\u00f3mez","sequence":"additional","affiliation":[{"name":"Biomedical Engineering Group, E.T.S.I. de Telecomunicaci\u00f3n, Universidad de Valladolid, 47011 Valladolid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8577-9559","authenticated-orcid":false,"given":"Jes\u00fas","family":"Poza","sequence":"additional","affiliation":[{"name":"Biomedical Engineering Group, E.T.S.I. de Telecomunicaci\u00f3n, Universidad de Valladolid, 47011 Valladolid, Spain"},{"name":"Instituto de Investigaci\u00f3n en Matem\u00e1ticas (IMUVA), Universidad de Valladolid, 47011 Valladolid, Spain"},{"name":"Instituto de Neurociencias de Castilla y Le\u00f3n (INCYL), Universidad de Salamanca, 37007 Salamanca, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1237-3424","authenticated-orcid":false,"given":"Gonzalo","family":"Guti\u00e9rrez-Tobal","sequence":"additional","affiliation":[{"name":"Biomedical Engineering Group, E.T.S.I. de Telecomunicaci\u00f3n, Universidad de Valladolid, 47011 Valladolid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Miguel","family":"Tola-Arribas","sequence":"additional","affiliation":[{"name":"Servicio de Neurolog\u00eda, Hospital Universitario R\u00edo Hortega, 47012 Valladolid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"M\u00f3nica","family":"Cano","sequence":"additional","affiliation":[{"name":"Servicio de Neurofisiolog\u00eda Cl\u00ednica, Hospital Universitario R\u00edo Hortega, 47012 Valladolid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Roberto","family":"Hornero","sequence":"additional","affiliation":[{"name":"Biomedical Engineering Group, E.T.S.I. de Telecomunicaci\u00f3n, Universidad de Valladolid, 47011 Valladolid, Spain"},{"name":"Instituto de Investigaci\u00f3n en Matem\u00e1ticas (IMUVA), Universidad de Valladolid, 47011 Valladolid, Spain"},{"name":"Instituto de Neurociencias de Castilla y Le\u00f3n (INCYL), Universidad de Salamanca, 37007 Salamanca, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2018,1,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Alzheimer\u2019s Association (2017). 2017 Alzheimer\u2019s disease facts and figures. 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