Lexico-Semantic Processing in Older Adults with Subjective Cognitive Decline: An Eye-Tracking Study

Poster Session E - Monday, April 15, 2024, 2:30 – 4:30 pm EDT, Sheraton Hall ABC

Marc-Antoine Akzam-Ouellette^1,3 (marc-antoine.akzam-ouellette@umontreal.ca), Léoni Labrecque^1,3, Isabelle Rouleau^2,3, Sven Joubert^1,3; ¹Université de Montréal, ²Université du Québec à Montréal, ³Centre de recherche de l'Institut universitaire de gériatrie de Montréal

In the continuum of Alzheimer's disease (AD), the clinical phase follows Mild Cognitive Impairment (MCI) and Subjective Cognitive Decline (SCD). Jessen et al. (2014, 2020) demonstrated that individuals with SCD have an increased risk of developing AD dementia over time, supporting a three-stage model of AD. Despite overall normal cognitive performance, specific disruptions in lexical-semantic functioning, such as challenges in naming pictures, are observed in SCD, hinting at a potential early cognitive marker of AD. Recent eye-tracking studies have unveiled distinctive visual patterns in individuals with MCI and AD compared to cognitively healthy participants (CS) during various cognitive tasks. Therefore, eye-tracking could be an effective tool to compare differences in visual analysis patterns during lexical-semantic processing in SCD relative to a cognitively healthy control group of participants. Sixty participants (30 SCD, 30 CS) took part in a task regarding the identification of known faces versus unknown faces. A significant interaction effect between groups and the 'missed identification' face category was observed (F[1,753] = 5.662, p < 0.05, η2= 0.01). Controls exhibited more saccades and fixations when viewing a known face, even when unable to identify it behaviorally. These results affirm the efficacy of eye-tracking in discerning visual pattern disparities in SCD participants relative to controls. Eye-tracking could present a non-invasive and cost-effective alternative to current invasive and expensive methods for identifying AD biomarkers, and underscores its potential as a precise diagnostic aid in the early stages of Alzheimer's disease.

Topic Area: METHODS: Other