Authors: Arlen Perez, Sylvie Ratté
Published: 2020-12-07
DOI: 10.1002/alz.043869
Source: Full article
AbstractBackgroundAmong the studies concerned with the description of changes in nonverbal communications, some authors have established a link between eye movement and AD [1]. In this presentation, we introduce a method to automatically analyze and evaluate the performance of AD patients during natural conversations through eye movements. This project was conducted as part of a research program funded by Natural Sciences and Engineering Research Council of Canada ( "Pattern recognition for the detection and monitoring of verbal and non‐verbal alterations in Alzheimer's disease", RGPIN‐2018‐05714).MethodWe analyzed 22 videos in the Carolinas Conversations Collection, a dataset where conversations with elderly people were recorded. These videos have 370 minutes approximately, with 17 subjects, 9 healthy controls (HC), and 8 AD patients. We tracked the eye movements through time in two ways, as a vector [Figure 1] and as landmarks on the eyes [Figure 2]. Then we trained classifiers to distinguish HCs and AD subjects, and performed the experiments using gaze vectors and eye landmarks as features (individually, combined).ResultWe obtain the performance of the classifiers measuring the accuracy, precision, recall, and ROC curve. Our results show that the combination of eye landmarks and gaze vectors features is strongly related with the AD condition. The classification sensitivity (ROC) is 77% performing with gaze vector features, 85% using the eyes landmarks in 3D, and combining both, we obtained 88% sensitivity (HC vs. AD) [Table 1].ConclusionThe automatic analysis of the eye movements could be a useful tool for clinicians and researchers studying early signs of AD. In future work, we will analyze facial expressions in order to study the link between verbal features (related to speech and content) and non‐verbal features (facial expressions, eye movements), and their correlations with AD. [1] Fernández G, Mandolesi P, Rotstein NP, Colombo O, Agamennoni O, Politi LE. Eye movement alterations during reading in patients with early Alzheimer disease. Invest Ophthalmol Vis Sci 2013;54:8345–52. https://doi.org/10.1167/iovs.13‐12877.