{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,29]],"date-time":"2026-04-29T21:32:19Z","timestamp":1777498339343,"version":"3.51.4"},"reference-count":97,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2021,3,6]],"date-time":"2021-03-06T00:00:00Z","timestamp":1614988800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000002","name":"National Institutes of Health","doi-asserted-by":"publisher","award":["NIH\/NIDCD R01 DC014475"],"award-info":[{"award-number":["NIH\/NIDCD R01 DC014475"]}],"id":[{"id":"10.13039\/100000002","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Brain Sciences"],"abstract":"<jats:p>Transcranial direct current stimulation (tDCS) over the left inferior frontal gyrus (IFG) was found to improve oral and written naming in post-stroke and primary progressive aphasia (PPA), speech fluency in stuttering, a developmental speech-motor disorder, and apraxia of speech (AOS) symptoms in post-stroke aphasia. This paper addressed the question of whether tDCS over the left IFG coupled with speech therapy may improve sound duration in patients with apraxia of speech (AOS) symptoms in non-fluent PPA (nfvPPA\/AOS) more than sham. Eight patients with non-fluent PPA\/AOS received either active or sham tDCS, along with speech therapy for 15 sessions. Speech therapy involved repeating words of increasing syllable-length. Evaluations took place before, immediately after, and two months post-intervention. Words were segmented into vowels and consonants and the duration of each vowel and consonant was measured. Segmental duration was significantly shorter after tDCS compared to sham and tDCS gains generalized to untrained words. The effects of tDCS sustained over two months post-treatment in trained and untrained sounds. Taken together, these results demonstrate that tDCS over the left IFG may facilitate speech production by reducing segmental duration. The results provide preliminary evidence that tDCS may maximize efficacy of speech therapy in patients with nfvPPA\/AOS.<\/jats:p>","DOI":"10.3390\/brainsci11030335","type":"journal-article","created":{"date-parts":[[2021,3,7]],"date-time":"2021-03-07T20:20:43Z","timestamp":1615148443000},"page":"335","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":26,"title":["Effects of tDCS on Sound Duration in Patients with Apraxia of Speech in Primary Progressive Aphasia"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9138-0939","authenticated-orcid":false,"given":"Charalambos","family":"Themistocleous","sequence":"first","affiliation":[{"name":"Department of Neurology, Johns Hopkins School of Medicine, Baltimore, MD 21210, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kimberly","family":"Webster","sequence":"additional","affiliation":[{"name":"Department of Otolaryngology, Johns Hopkins Medicine, Baltimore, MD 21210, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kyrana","family":"Tsapkini","sequence":"additional","affiliation":[{"name":"Department of Neurology, Johns Hopkins School of Medicine, Baltimore, MD 21210, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,3,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"343","DOI":"10.1016\/j.bandl.2006.01.008","article-title":"Clinical and anatomical correlates of apraxia of speech","volume":"97","author":"Ogar","year":"2006","journal-title":"Brain Lang."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"580","DOI":"10.1097\/WCO.0b013e3280109260","article-title":"Disorders of speech and language: Aphasia, apraxia and dysarthria","volume":"19","author":"Jordan","year":"2006","journal-title":"Curr Opin Neurol"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"43","DOI":"10.1016\/j.bandl.2014.01.004","article-title":"The neuroanatomy of pure apraxia of speech in stroke","volume":"129","author":"Jones","year":"2014","journal-title":"Brain Lang."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"346","DOI":"10.1080\/13554794.2016.1172645","article-title":"Brain damage associated with apraxia of speech: Evidence from case studies","volume":"22","author":"Moser","year":"2016","journal-title":"Neurocase"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"462","DOI":"10.1044\/jshd.3804.462","article-title":"A treatment for apraxia of speech in adults","volume":"38","author":"Rosenbek","year":"1973","journal-title":"J. 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