{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,25]],"date-time":"2026-08-25T01:36:57Z","timestamp":1787621817667,"version":"build-2736575974"},"reference-count":60,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2024,1,6]],"date-time":"2024-01-06T00:00:00Z","timestamp":1704499200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Brain Sciences"],"abstract":"<jats:p>Apraxia of speech is a persistent speech motor disorder that affects speech intelligibility. Studies on speech motor disorders with transcranial Direct Current Stimulation (tDCS) have been mostly directed toward examining post-stroke aphasia. Only a few tDCS studies have focused on apraxia of speech or childhood apraxia of speech (CAS), and no study has investigated individuals with CAS and Trisomy 21 (T21, Down syndrome). This N-of-1 randomized trial examined the effects of tDCS combined with a motor learning task in developmental apraxia of speech co-existing with T21 (ReBEC RBR-5435x9). The accuracy of speech sound production of nonsense words (NSWs) during Rapid Syllable Transition Training (ReST) over 10 sessions of anodal tDCS (1.5 mA, 25 cm) over Broca\u2019s area with the cathode over the contralateral region was compared to 10 sessions of sham-tDCS and four control sessions in a 20-year-old male individual with T21 presenting moderate\u2013severe childhood apraxia of speech (CAS). The accuracy for NSW production progressively improved (gain of 40%) under tDCS (sham-tDCS and control sessions showed &lt; 20% gain). A decrease in speech severity from moderate\u2013severe to mild\u2013moderate indicated transfer effects in speech production. Speech accuracy under tDCS was correlated with Wernicke\u2019s area activation (P3 current source density), which in turn was correlated with the activation of the left supramarginal gyrus and the Sylvian parietal\u2013temporal junction. Repetitive bihemispheric tDCS paired with ReST may have facilitated speech sound acquisition in a young adult with T21 and CAS, possibly through activating brain regions required for phonological working memory.<\/jats:p>","DOI":"10.3390\/brainsci14010058","type":"journal-article","created":{"date-parts":[[2024,1,8]],"date-time":"2024-01-08T06:12:58Z","timestamp":1704694378000},"page":"58","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Enhancing Speech Rehabilitation in a Young Adult with Trisomy 21: Integrating Transcranial Direct Current Stimulation (tDCS) with Rapid Syllable Transition Training for Apraxia of Speech"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2196-2490","authenticated-orcid":false,"given":"Ester Miyuki","family":"Nakamura-Palacios","sequence":"first","affiliation":[{"name":"Department of Physiological Sciences, Federal University of Esp\u00edrito Santo, Vit\u00f3ria 29040-090, ES, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Aldren Thomazini","family":"Fal\u00e7oni J\u00fanior","sequence":"additional","affiliation":[{"name":"Superior School of Sciences of the Santa Casa de Miseric\u00f3rdia de Vit\u00f3ria (EMESCAM), Vit\u00f3ria 29045-402, ES, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gabriela Lolli","family":"Tanese","sequence":"additional","affiliation":[{"name":"Clinic of Speech-Language Pathology, Eldorado Business Tower, Goi\u00e2nia 74280-010, GO, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4529-7090","authenticated-orcid":false,"given":"Ana Carla Estellita","family":"Vogeley","sequence":"additional","affiliation":[{"name":"Department of Speech and Language Pathology, Federal University of Para\u00edba, Jo\u00e3o Pessoa 58051-900, PB, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9970-5478","authenticated-orcid":false,"given":"Aravind Kumar","family":"Namasivayam","sequence":"additional","affiliation":[{"name":"Department of Speech-Language Pathology, University of Toronto, Toronto, ON M5G 1V7, Canada"},{"name":"Speech Research Centre Inc., Brampton, ON L7A 2T1, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,1,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"10","DOI":"10.3104\/reports.301","article-title":"Speech intelligibility and childhood verbal apraxia in children with Down syndrome","volume":"10","author":"Kumin","year":"2006","journal-title":"Down Syndr. 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