{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,8]],"date-time":"2026-02-08T07:56:10Z","timestamp":1770537370845,"version":"3.49.0"},"reference-count":53,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2015,12,29]],"date-time":"2015-12-29T00:00:00Z","timestamp":1451347200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"CHUNG Moon Soul Research Center for Bio Information and Bio Electronics","award":["R01-2007-000-21094-0"],"award-info":[{"award-number":["R01-2007-000-21094-0"]}]},{"name":"CHUNG Moon Soul Research Center for Bio Information and Bio Electronics","award":["M10644000028-06N4400-02810"],"award-info":[{"award-number":["M10644000028-06N4400-02810"]}]},{"DOI":"10.13039\/501100004084","name":"Korea Science and Engineering Foundation","doi-asserted-by":"publisher","award":["20090093897"],"award-info":[{"award-number":["20090093897"]}],"id":[{"id":"10.13039\/501100004084","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100004084","name":"Korea Science and Engineering Foundation","doi-asserted-by":"publisher","award":["20090083561"],"award-info":[{"award-number":["20090083561"]}],"id":[{"id":"10.13039\/501100004084","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>Parkinson\u2019s disease (PD) and Alzheimer\u2019s disease (AD) can coexist in severely affected; elderly patients. Since they have different pathological causes and lesions and consequently require different treatments; it is critical to distinguish PD-related dementia (PD-D) from AD. Conventional electroencephalograph (EEG) analysis has produced poor results. This study investigated the possibility of using relative wavelet energy (RWE) and wavelet coherence (WC) analysis to distinguish between PD-D patients; AD patients and healthy elderly subjects. In EEG signals; we found that low-frequency wavelet energy increased and high-frequency wavelet energy decreased in PD-D patients and AD patients relative to healthy subjects. This result suggests that cognitive decline in both diseases is potentially related to slow EEG activity; which is consistent with previous studies. More importantly; WC values were lower in AD patients and higher in PD-D patients compared with healthy subjects. In particular; AD patients exhibited decreased WC primarily in the \u03b3 band and in links related to frontal regions; while PD-D patients exhibited increased WC primarily in the \u03b1 and \u03b2 bands and in temporo-parietal links. Linear discriminant analysis (LDA) of RWE produced a maximum accuracy of 79.18% for diagnosing PD-D and 81.25% for diagnosing AD. The discriminant accuracy was 73.40% with 78.78% sensitivity and 69.47% specificity. In distinguishing between the two diseases; the maximum performance of LDA using WC was 80.19%. We suggest that using a wavelet approach to evaluate EEG results may facilitate discrimination between PD-D and AD. In particular; RWE is useful for differentiating individuals with and without dementia and WC is useful for differentiating between PD-D and AD.<\/jats:p>","DOI":"10.3390\/e18010008","type":"journal-article","created":{"date-parts":[[2015,12,29]],"date-time":"2015-12-29T10:00:08Z","timestamp":1451383208000},"page":"8","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":44,"title":["Wavelet Energy and Wavelet Coherence as EEG Biomarkers for the Diagnosis of Parkinson\u2019s Disease-Related Dementia and Alzheimer\u2019s Disease"],"prefix":"10.3390","volume":"18","author":[{"given":"Dong-Hwa","family":"Jeong","sequence":"first","affiliation":[{"name":"Department of Bio and Brain Engineering, KAIST, Daejeon 34141, Korea"}]},{"given":"Young-Do","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Neurology, Incheon St. Mary\u2019s Hospital, College of Medicine, The Catholic University of Korea, Incheon 21431, Korea"}]},{"given":"In-Uk","family":"Song","sequence":"additional","affiliation":[{"name":"Department of Neurology, Incheon St. Mary\u2019s Hospital, College of Medicine, The Catholic University of Korea, Incheon 21431, Korea"}]},{"given":"Yong-An","family":"Chung","sequence":"additional","affiliation":[{"name":"Department of Radiology, Incheon St. Mary\u2019s Hospital, College of Medicine, The Catholic University of Korea, Incheon 21431, Korea"}]},{"given":"Jaeseung","family":"Jeong","sequence":"additional","affiliation":[{"name":"Department of Bio and Brain Engineering, KAIST, Daejeon 34141, Korea"}]}],"member":"1968","published-online":{"date-parts":[[2015,12,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"100","DOI":"10.1002\/mds.870050203","article-title":"A hypothesis on the pathophysiological mechanisms that underlie levodopa- or dopamine agonist-induced dyskinesia in Parkinson\u2019s disease: Implications for future strategies in treatment","volume":"5","author":"Crossman","year":"1990","journal-title":"Mov. 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