Stability Over Time of Word Syllable Duration for Speakers With Acquired Apraxia of Speech.

PURPOSE: Neurogenic speech and language disorders-such as acquired apraxia of speech (AOS) and aphasia with phonemic paraphasia (APP)-are often misdiagnosed due to similarities in clinical presentation. Word syllable duration (WSD)-a measure of average syllable length in multisyllabic words-serves as a proxy for speech rate, which is an important and arguably more objective clinical characteristic of AOS and APP. This study reports stability of WSD over time for speakers with AOS (and aphasia). METHOD: Twenty-nine participants with AOS and aphasia (11 women and 18 men, Mage = 53.5 years, SD = 13.3) repeated 30 multisyllabic words (of three-, four-, and five-syllable lengths) on three occasions across 4 weeks. WSDs were calculated for each word and then averaged across each list (i.e., word length), as well as across combined lists (i.e., all 30 words) to yield four WSDs for each participant at each time point. Stability over time was calculated using Friedman's test for the group and using Spearman's rho for the individual level. Effects of time and word length were examined using robust mixed-effects linear regression. RESULTS: Friedman's tests and correlations indicated no significant difference in WSDs across sampling occasions for each word length separately or combined. WSD correlated positively with AOS severity and negatively with intelligibility but was not correlated with aphasia severity. Regression analyses confirmed WSD to be stable over time, while WSD calculated from only five tokens (i.e., WSD-5) was less stable over time. CONCLUSIONS: Results indicate that WSD can be a stable measure over time, at the individual and group level, providing support for its use in diagnosis and/or as an outcome measure, both clinically and for research. In general, WSD outperformed WSD-5, suggesting that it may be better to calculate WSD from more than five tokens. Stability of WSD in other populations and suitability for differential diagnosis need to be determined. Currently, differentiating disorders by speaking rate, alone, is not recommended. SUPPLEMENTAL MATERIAL: https://doi.org/10.23641/asha.25438735.

White Matter Hyperintensities as a Predictor of Aphasia Recovery.

OBJECTIVE: To examine the relation between baseline white matter hyperintensities (WMH) and change in naming, content production, and efficiency after treatment in subacute aphasia. We hypothesized that more severe baseline WMH would result in less improvement with treatment. DESIGN: Retrospective analysis of a cohort from a double-blind randomized controlled trial (RCT). SETTING: Outpatient clinical setting or participant home. PARTICIPANTS: We retrospectively reviewed imaging and behavioral data for 52 participants with subacute aphasia due to left-hemisphere ischemic stroke enrolled in the RCT. RCT inclusion criteria: English proficiency, normal/corrected-to-normal hearing/vision, and no history of neurologic conditions other than the stroke resulting aphasia. One participant with a chronic right-hemisphere lesion was retained as she presented with no residual deficits on neurologic examination. Individuals with scalp sensitivities or on medications that lower seizure threshold or any N-methyl-D-aspartate (NMDA) antagonists were excluded. Of the 52 participants, for this analysis, 2 were excluded for not having a magnetic resonance imaging, and 7 were excluded for not participating in treatment or pre/post assessment for at least 1 outcome, resulting in final sample of 43 participants (20 women sex, M [SD] age=64.4 [11.9] and M [SD] education=14.9 [3.1] years). INTERVENTIONS: Participants received 15 sessions (2-3 times/week) of computerized lexical-semantic (ie, verification) treatment with [sham/active] transcranial direct current stimulation (tDCS). Sessions were approximately 45 minutes each (tDCS for first 20 minutes). MAIN OUTCOME MEASURES: Naming accuracy, content units (CUs, a measure of semantically accurate production), and efficiency (ie, syllables/CU) on a picture description task. RESULTS: Periventricular WMH severity was independently associated with recovery in picture naming for the active tDCS group. Deep WMH severity was associated with recovery for CU production for the sham tDCS group. CONCLUSION: Baseline periventricular and deep WMH, among other factors, may be an important consideration for prognosis and treatment planning, especially when considered in conjunction with tDCS treatment.