{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,21]],"date-time":"2026-07-21T18:04:02Z","timestamp":1784657042581,"version":"3.55.0"},"reference-count":46,"publisher":"Public Library of Science (PLoS)","issue":"7","license":[{"start":{"date-parts":[[2026,7,21]],"date-time":"2026-07-21T00:00:00Z","timestamp":1784592000000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000055","name":"National Institute on Deafness and Other Communication Disorders","doi-asserted-by":"publisher","award":["F31 DC019032"],"award-info":[{"award-number":["F31 DC019032"]}],"id":[{"id":"10.13039\/100000055","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000055","name":"National Institute on Deafness and Other Communication Disorders","doi-asserted-by":"publisher","award":["R01 DC016270"],"award-info":[{"award-number":["R01 DC016270"]}],"id":[{"id":"10.13039\/100000055","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000055","name":"National Institute on Deafness and Other Communication Disorders","doi-asserted-by":"publisher","award":["T32 DC013017"],"award-info":[{"award-number":["T32 DC013017"]}],"id":[{"id":"10.13039\/100000055","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000055","name":"National Institute on Deafness and Other Communication Disorders","doi-asserted-by":"publisher","award":["R01 DC020867"],"award-info":[{"award-number":["R01 DC020867"]}],"id":[{"id":"10.13039\/100000055","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Rafik B. Hariri Institute for Computing and Computational Science and Engineering","award":["Graduate Fellowship"],"award-info":[{"award-number":["Graduate Fellowship"]}]},{"DOI":"10.13039\/100013453","name":"American Speech-Language-Hearing Association","doi-asserted-by":"publisher","award":["New Century Doctoral Scholarship"],"award-info":[{"award-number":["New Century Doctoral Scholarship"]}],"id":[{"id":"10.13039\/100013453","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100008133","name":"Dudley Allen Sargent Research Fund","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100008133","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100007161","name":"Boston University","doi-asserted-by":"publisher","award":["Undergraduate Research Opportunities Program"],"award-info":[{"award-number":["Undergraduate Research Opportunities Program"]}],"id":[{"id":"10.13039\/100007161","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS One"],"abstract":"<jats:p>\n                    This study assessed the ability of three acoustic measures of vowel space, two token-based and one trajectory-based, to quantify speech differences in people with Parkinson\u2019s disease compared to controls and correlations with speech intelligibility. Fifty-six speakers (28 people with Parkinson\u2019s and 28 controls) read a custom reading passage containing corner vowels. For token-based measures, the triangular vowel space area (tVSA) in kHz\n                    <jats:sup>2<\/jats:sup>\n                    and the unitless ratio of vowel articulation index (VAI) were calculated. For the trajectory-based measure, the articulatory-acoustic vowel space (AAVS) in kHz\n                    <jats:sup>2<\/jats:sup>\n                    was calculated. Speakers also read five unique sentences varying in word length, which were used to collect speech intelligibility ratings. Analyses of Variance revealed that all vowel space measures yielded group differences. Binary logistic regression revealed that only the token-based measures were able to statistically discriminate PwPD from controls, however all models performed poorly (R\n                    <jats:sup>2<\/jats:sup>\n                    \u2009&lt;\u20090.113). Linear regressions showed that token-based metrics were statistically related to intelligibility and that the VAI yielded the best model for the current sample. The results support that token-based measures are well-suited for quantifying changes in acoustic vowel space and perceived speech intelligibility in people with Parkinson\u2019s. Future work should examine the generalizability of these findings to other motor speech disorders as well as across different speech stimuli.\n                  <\/jats:p>","DOI":"10.1371\/journal.pone.0353680","type":"journal-article","created":{"date-parts":[[2026,7,21]],"date-time":"2026-07-21T17:23:04Z","timestamp":1784654584000},"page":"e0353680","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":0,"title":["Comparing token-based and trajectory-based vowel space metrics for assessing speech in Parkinson\u2019s disease"],"prefix":"10.1371","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0410-8487","authenticated-orcid":true,"given":"Defne","family":"Abur","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Megan","family":"Cushman","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Courtney J.","family":"Dunsmuir","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cara E.","family":"Stepp","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"340","published-online":{"date-parts":[[2026,7,21]]},"reference":[{"issue":"3","key":"pone.0353680.ref001","doi-asserted-by":"crossref","first-page":"104","DOI":"10.3109\/09638289709166834","article-title":"The prevalence of verbal communication disability in patients with Parkinson\u2019s disease","volume":"19","author":"C Coates","year":"1997","journal-title":"Disabil Rehabil"},{"issue":"5","key":"pone.0353680.ref002","doi-asserted-by":"crossref","first-page":"825","DOI":"10.1044\/2019_PERS-SIG3-2019-0001","article-title":"Based updates in swallowing and communication dysfunction in parkinson disease: implications for evaluation and management","volume":"4","author":"C Broadfoot","year":"2019","journal-title":"Perspect ASHA Spec Interest Groups"},{"key":"pone.0353680.ref003","doi-asserted-by":"crossref","unstructured":"Ferguson SH, Kewley-Port D. 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