Production of Sentential Negation in German and Italian Non-fluent Aphasia

Area of Science:

• Linguistics
• Neuroscience
• Psychology

Background:

• Investigating sentential negation in persons with non-fluent aphasia (PWAs) across languages is limited by small sample sizes.
• Existing theories on (morpho)syntactic impairment in PWAs focus on factors like verb movement, Negation Phrase position, and negation interpretability.

Purpose of the Study:

• To examine the sentence production abilities of German and Italian PWAs constructing negative sentences.
• To determine the influence of verbal working memory (WM) capacity and education on task performance and negation production in PWAs.

Main Methods:

• A sentence anagram task was used to assess the construction of negative and affirmative declarative sentences.
• Participants included 9 German and 7 Italian PWAs, alongside 14 German and 11 Italian healthy controls matched for age and education.
• Generalized linear mixed-effects models were applied to analyze the data.

Main Results:

• No significant differences were found in the production of negative versus affirmative sentences by either PWA group.
• Verbal WM capacity significantly affected overall task performance.
• No interaction was observed between verbal WM capacity and the production of negative versus affirmative sentences; education level did not impact performance.

Conclusions:

• The findings suggest that sentence negation production is not inherently more challenging than affirmative sentence production for persons with non-fluent aphasia.
• Verbal working memory capacity plays a general role in sentence construction tasks for this population.
• Further research can explore the implications of these results for various linguistic theories of aphasia.