Stimulus- and person-level variables in aphasia (Braun & Kiran, 2022)

Purpose: The impact of stimulus-level psycholinguistic variables and person-level semantic and phonological processing skills on treatment outcomes in individuals with aphasia requires further examination to inform clinical decision making in treatment prescription and stimuli selection. This study investigated the influence of stimulus-level psycholinguistic properties and person-level semantic and phonological processing skills on word production accuracy and treatment response.

Method: This retrospective analysis included 35 individuals with chronic, poststroke aphasia, 30 of whom completed typicality-based semantic feature treatment. Mixed-effects logistic regression models were used to predict binary naming accuracy (a) at baseline and (b) over the course of treatment using stimulus-level psycholinguistic word properties and person-level semantic and phonological processing skills as predictors.

Results: In baseline naming, words with less complex lexical–semantic and phonological properties showed greater predicted accuracy. There was also an interaction at baseline between stimulus-level lexical–semantic properties and person-level semantic processing skills in predicting baseline naming accuracy. With treatment, words that were more complex from a lexical–semantic standpoint (vs. less complex) and less complex from a phonological standpoint (vs. more complex) improved more. Individuals with greater baseline semantic and phonological processing skills showed a greater treatment response.

Conclusions: This study suggests that future clinical research and clinical work should consider semantic and phonological properties of words in selecting stimuli for semantically based treatment. Furthermore, future clinical research should continue to evaluate baseline individual semantic and phonological profiles as predictors of response to semantically based treatment.

Supplemental Material S1. References: R packages.

Supplemental Material S2. Histograms of psycholinguistic variables.

Supplemental Material S3. Correlation matrix for psycholinguistic variables.

Supplemental Material S4. Notes about preliminary models including level of education.

Supplemental Material S5. Model output for primary research questions.

Supplemental Material S6. Model output for follow-up comparisons of slopes.

Braun, E. J., & Kiran, S. (2022). Stimulus- and person-level variables influence word production and response to anomia treatment for individuals with chronic poststroke aphasia. Journal of Speech, Language, and Hearing Research. Advance online publication. https://doi.org/10.1044/2022_JSLHR-21-00527