{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,2]],"date-time":"2026-06-02T13:34:13Z","timestamp":1780407253231,"version":"3.54.1"},"reference-count":50,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2013,5,21]],"date-time":"2013-05-21T00:00:00Z","timestamp":1369094400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The work presented here is part of a larger study to identify novel technologies and biomarkers for early Alzheimer disease (AD) detection and it focuses on evaluating the suitability of a new approach for early AD diagnosis by non-invasive methods. The purpose is to examine in a pilot study the potential of applying intelligent algorithms to speech features obtained from suspected patients in order to contribute to the improvement of diagnosis of AD and its degree of severity. In this sense, Artificial Neural Networks (ANN) have been used for the automatic classification of the two classes (AD and control subjects). Two human issues have been analyzed for feature selection: Spontaneous Speech and Emotional Response. Not only linear features but also non-linear ones, such as Fractal Dimension, have been explored. The approach is non invasive, low cost and without any side effects. Obtained experimental results were very satisfactory and promising for early diagnosis and classification of AD patients.<\/jats:p>","DOI":"10.3390\/s130506730","type":"journal-article","created":{"date-parts":[[2013,5,21]],"date-time":"2013-05-21T14:22:12Z","timestamp":1369146132000},"page":"6730-6745","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":145,"title":["On the Selection of Non-Invasive Methods Based on Speech Analysis Oriented to Automatic Alzheimer Disease Diagnosis"],"prefix":"10.3390","volume":"13","author":[{"given":"Karmele","family":"L\u00f3pez-de-Ipi\u00f1a","sequence":"first","affiliation":[{"name":"Systems Engineering and Automation Department, University of the Basque Country UPV\/EHU, Donostia 20018, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jesus-Bernardino","family":"Alonso","sequence":"additional","affiliation":[{"name":"Signal and Communication Departament (DSC), Institute for Technological Development and Innovation in Communications (IDeTIC), University of Las Palmas de Gran Canaria (ULPGC), Campus of Tafira, Las Palmas de Gran Canaria 35017, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Carlos","family":"Travieso","sequence":"additional","affiliation":[{"name":"Signal and Communication Departament (DSC), Institute for Technological Development and Innovation in Communications (IDeTIC), University of Las Palmas de Gran Canaria (ULPGC), Campus of Tafira, Las Palmas de Gran Canaria 35017, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6534-1979","authenticated-orcid":false,"given":"Jordi","family":"Sol\u00e9-Casals","sequence":"additional","affiliation":[{"name":"Digital Technologies Group, University of Vic, Sagrada fam\u00edlia 7, Vic 08500, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Harkaitz","family":"Egiraun","sequence":"additional","affiliation":[{"name":"Systems Engineering and Automation Department, University of the Basque Country UPV\/EHU, Donostia 20018, Spain"},{"name":"Research Center for Experimental Marine Biology and Biotechnology, Plentzia Marine Station, University of the Basque Country, Plentzia 48620, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0605-1282","authenticated-orcid":false,"given":"Marcos","family":"Faundez-Zanuy","sequence":"additional","affiliation":[{"name":"Escola Universitaria Polit\u00e8cnica de Matar\u00f3 (UPC), Tecnocampus, Matar\u00f3, Barcelona 08302, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Aitzol","family":"Ezeiza","sequence":"additional","affiliation":[{"name":"Systems Engineering and Automation Department, University of the Basque Country UPV\/EHU, Donostia 20018, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nora","family":"Barroso","sequence":"additional","affiliation":[{"name":"Systems Engineering and Automation Department, University of the Basque Country UPV\/EHU, Donostia 20018, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Miriam","family":"Ecay-Torres","sequence":"additional","affiliation":[{"name":"CITA-Alzheimer Foundation, San Sebastian 20009, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pablo","family":"Martinez-Lage","sequence":"additional","affiliation":[{"name":"CITA-Alzheimer Foundation, San Sebastian 20009, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Unai","family":"Lizardui","sequence":"additional","affiliation":[{"name":"Systems Engineering and Automation Department, University of the Basque Country UPV\/EHU, Donostia 20018, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2013,5,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"939","DOI":"10.1212\/WNL.34.7.939","article-title":"Clinical diagnosis of Alzheimer's disease: Report of the National Institute on Aging-Alzheimer's Association workgroup on Alzheimer's disease","volume":"24","author":"McKhann","year":"1984","journal-title":"Neurology"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"263","DOI":"10.1016\/j.jalz.2011.03.005","article-title":"The diagnosis of dementia due to Alzheimer's disease: Recommendations from the National Institute on Aging-Alzheimer's Association workgroups on diagnostic guidelines for Alzheimer's disease","volume":"7","author":"McKhann","year":"2011","journal-title":"Alzheimers Dement."},{"key":"ref_3","unstructured":"Alzheimer's Association. 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