Assessment of Lexical Markers in Older Black/African American Adults at Risk for Alzheimer’s Disease

• Kira Jefferson, Cognitive Science, University of Delaware

• Faith Stagge, Communication Sciences & Disorders, University of Delaware
• Alyssa M. Lanzi, Communication Sciences & Disorders, University of Delaware

Older adults at risk for mild cognitive impairment (MCI) due to Alzheimer’s disease (AD) often have lexical retrieval difficulties and decreased lexical diversity in connected speech and language (CSL) tasks when compared to those without MCI (Filiou et al., 2020). However, the majority of these findings often reflect homogeneous ethnoracial samples (Evans et al., 2022). The evaluation of lexical markers to assess cognitive status has been extended to other ethnocultural backgrounds, such as Black/African American adults, when describing pictures, but not in other CSL tasks, like storytelling (Evans et al., 2022). Therefore, this study aims to 1) characterize lexical markers in connected speech and language produced during a storytelling task and 2) explore differences in lexical marker production between Black/African American and non-Hispanic White adults at risk for MCI due to AD. CSL samples were drawn from the DementiaBank, a shared research database to study language changes associated with MCI and dementia due to AD (Lanzi et al., 2023). Participants completed a protocol of six different CSL tasks, including retelling the story of Cinderella (Grimes, 2005). This data was analyzed using the Wilcoxon-Rank Sum tests for three lexical markers: types (i.e., number of different words), tokens (i.e., number of total words), and type-token ratio (i.e., the number of different words divided by the number of total words). Our findings revealed that Black/African American adults at risk for dementia due to AD produce a greater number of lexical types and tokens during a storytelling task; however, this difference was not statistically significant compared to their non-Hispanic White counterparts. This study provides further evidence that analyzing CSL in storytelling can be an effective tool for evaluating cognitive decline, regardless of ethnocultural differences.