Sentence production in semantic dementia (Koukoulioti et al., 2018)

Purpose: Language production in semantic dementia
(SD) is characterized by a lexical–semantic deficit
and largely preserved argument structure and inflection
production. This study investigates (a) the effect
of argument structure on verb retrieval and (b) the
interrelation between inflection marking and verb retrieval
in SD.
Method: Seven individuals with SD and 7 healthy controls
performed 2 sentence elicitation tasks. In Experiment 1,
participants described the action taking place in a video.
In Experiment 2, they watched the same videos preceded
by a phrase prompting the production of past tense.
Three verb classes were tested: (a) unergative (e.g., to
walk), (b) unaccusative (e.g., to fall ), and (c) transitive with
1 object (e.g., to read a book).
Results: There was not any quantitative difference among
the verb classes in Experiment 1, but error analysis hinted
at difficulties related with argument structure complexity.
The findings of Experiment 2 suggest no general effect of
inflection on verb retrieval; nevertheless, inflection marking
impeded the retrieval of verbs with complex argument
structure. Large individual variation was established.
Conclusions: Argument structure complexity may challenge
speakers with SD. Verb retrieval and inflection marking
seem to interrelate at the expense of the former. Inflection
production may be affected at severe stages of the disease.

Supplemental Material S1. Description of the language profile of the patients and details on the selection criteria.

Supplemental Material S2. Comments on the construction of the material: Experiment 1.

Supplemental Material S3. Verbs used in each verb class.

Supplemental Material S4. Comments on the construction of the material: Experiment 2.

Supplemental Material S5. Overview of the material used in Experiment 2.

Supplemental Material S6. Comparisons of the individual scores to the scores of the control group.

Supplemental Material S7. Comparison of the individual patient performance to the performance of the control group in Experiment 1.

Supplemental Material S8. Comparison of the individual patient performance to the performance of the control group in Experiment 2.

Supplemental Material S9. Comparison of the individual patients to the control group with respect to the difference in the scores between the tasks.

Koukoulioti, V., Stavrakaki, S., Konstantinopoulou, E., & Ioannidisd, P. (2018). Lexical and grammatical factors in sentence production in semantic dementia: Insights from Greek. Journal of Speech, Language, and Hearing Research, 61, 870–886. https://doi.org/10.1044/2017_JSLHR-L-17-0024