{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,9]],"date-time":"2026-02-09T22:21:00Z","timestamp":1770675660044,"version":"3.49.0"},"reference-count":31,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,2,9]],"date-time":"2026-02-09T00:00:00Z","timestamp":1770595200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Neurol."],"abstract":"\n Background<\/jats:title>\n An objective topological analysis for any arbitrary network was provided by graph theory, which was implemented to reveal topological properties of brain networks in a wide range of neurodegenerative diseases.<\/jats:p>\n <\/jats:sec>\n \n Objectives<\/jats:title>\n To investigate the difference of the topology of speech graphs among parkinsonian-type multiple system atrophy patients (MSA-P), idiopathic Parkinson\u2019s disease (PD) patients, and healthy controls (HC). To explore the effect of levodopa on the topology of speech graphs in MSA-P and PD patients.<\/jats:p>\n <\/jats:sec>\n \n Methods<\/jats:title>\n \n We applied a graph analysis of topology of speech graphs in MSA-P patients (\n N<\/jats:italic>\n \u202f=\u202f39), idiopathic PD patients (\n N<\/jats:italic>\n \u202f=\u202f51), and HC (\n N<\/jats:italic>\n \u202f=\u202f51). All participants were assessed by a well-established semantic fluency test (animal). Participants\u2019 verbal reactions were listed and represented as speech graphs with directionality.\n <\/jats:p>\n <\/jats:sec>\n \n Results<\/jats:title>\n \n MSA-P patients mentioned more about their memory and remaining time than PD patients (\n p<\/jats:italic>\n \u202f&lt;\u202f0.001) and HC (\n p<\/jats:italic>\n \u202f&lt;\u202f0.001). Moreover, MSA-P patients\u2019 speech graphs exhibited fewer nodes (PD:\n p<\/jats:italic>\n \u202f=\u202f0.004; HC:\n p<\/jats:italic>\n \u202f&lt;\u202f0.001), higher density (PD:\n p<\/jats:italic>\n \u202f=\u202f0.007; HC:\n p<\/jats:italic>\n \u202f&lt;\u202f0.001), smaller diameter (PD:\n p<\/jats:italic>\n \u202f=\u202f0.004; HC:\n p<\/jats:italic>\n \u202f&lt;\u202f0.001), and smaller average shortest path (PD:\n p<\/jats:italic>\n \u202f=\u202f0.002; HC:\n p<\/jats:italic>\n \u202f&lt;\u202f0.001) than both PD patients and HC. Compared with PD patients and healthy adults, the MSA-P patients generated denser and smaller speech graphs. Importantly, in MSA-P, the positive correlations between levodopa equivalent daily dose and diameter (\n r<\/jats:italic>\n \u202f=\u202f0.39,\n p<\/jats:italic>\n \u202f=\u202f0.017) and average shortest path (\n r<\/jats:italic>\n \u202f=\u202f0.38,\n p<\/jats:italic>\n \u202f=\u202f0.017) were obtained, suggesting that higher levodopa doses were associated with producing sparser and larger speech graphs in MSA-P patients. However, there was no significant correlation between levodopa equivalent daily dose and graph indices in PD patients.\n <\/jats:p>\n <\/jats:sec>\n \n Conclusion<\/jats:title>\n MSA-P patients\u2019 speech graphs were denser and smaller than both PD patients and healthy adults. The graph analysis of semantic fluency can differentiate MSA-P from PD to some extent. Importantly, in MSA-P patients, the impaired speech topology can be partially restored by levodopa.<\/jats:p>\n <\/jats:sec>","DOI":"10.3389\/fneur.2026.1746101","type":"journal-article","created":{"date-parts":[[2026,2,9]],"date-time":"2026-02-09T05:22:23Z","timestamp":1770614543000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["The effect of levodopa on speech graphs in non-demented patients with multiple system atrophy and Parkinson\u2019s disease"],"prefix":"10.3389","volume":"17","author":[{"given":"Jingyue","family":"Liu","sequence":"first","affiliation":[{"name":"National Clinical Research Center for Geriatric Disorders, Xuanwu Hospital of Capital Medical University","place":["Beijing, China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yan","family":"Zhao","sequence":"additional","affiliation":[{"name":"Department of Rehabilitation Medicine, Jinan Third People\u2019s Hospital","place":["Jinan, China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jinghong","family":"Ma","sequence":"additional","affiliation":[{"name":"Department of Neurology, Xuanwu Hospital of Capital Medical University","place":["Beijing, China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Guanyu","family":"Zhang","sequence":"additional","affiliation":[{"name":"China Institute of Sport Science","place":["Beijing, China"]}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1965","published-online":{"date-parts":[[2026,2,9]]},"reference":[{"key":"ref1","doi-asserted-by":"publisher","first-page":"249","DOI":"10.1056\/NEJMra1311488","article-title":"Multiple-system atrophy","volume":"372","author":"Fanciulli","year":"2015","journal-title":"N Engl J Med"},{"key":"ref2","doi-asserted-by":"publisher","first-page":"102","DOI":"10.1002\/nau.20948","article-title":"Pelvic organ dysfunction is more prevalent and severe in MSA-P compared to 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