Simultaneous Analysis of Microsaccades and Pupil Size Variations in Age-Related Cognitive Impairment Using
Seokjun Oh1, Tahsin Nairuz1, Sung-Jun Park2
1Department of Biomedical Engineering, Keimyung University, Daegu 42601, Republic of Korea.
Journal of Eye Movement Research
|March 24, 2026
Summary
Ocular biomarkers like microsaccades and pupil size changes show promise for detecting age-related cognitive decline. Eye-tracking reveals altered eye movements and pupil responses linked to lower cognitive scores, offering a non-invasive screening method.
Area of Science:
- Neuroscience
- Ophthalmology
- Gerontology
Background:
- Age-related cognitive impairment is a precursor to neurodegenerative diseases like Alzheimer's.
- Objective, non-invasive biomarkers are needed for early detection of neurological changes.
- Eye-tracking technology offers potential for analyzing physiological indicators.
Purpose of the Study:
- To investigate microsaccadic eye movements and pupil size variations as ocular biomarkers for age-related cognitive impairment.
- To assess the association between these ocular measures and cognitive function in different age groups.
Main Methods:
- Simultaneous eye-tracking analysis of microsaccades and pupil size.
- Recruitment of 70 participants across three age groups (20s, 60s, 70s).
- Cognitive assessment using MMSE-K to categorize older adults into normal and impaired subgroups.
Main Results:
- Microsaccade frequency increased significantly with age and was higher in individuals with lower cognitive scores (p < 0.01).
- Pupil size variation (constriction/dilation rates) decreased with age.
- Pupil response speed remained consistent across age groups.
Conclusions:
- Involuntary ocular responses, including microsaccades and pupil dynamics, are associated with age-related cognitive decline.
- A dual-biomarker approach using eye-tracking provides a quantitative, non-invasive method for cognitive assessment.
- Further research with larger cohorts and AD patients is needed to validate diagnostic utility.
