AccScience Publishing / AIH / Online First / DOI: 10.36922/AIH026320107
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Narayana D. Reddy
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ORIGINAL RESEARCH ARTICLE

Age-invariant functional retinal biomarkers for Alzheimer’s disease using adversarial deep learning

Narayana D. Reddy1* ,  Mallikarjun C. Sarsamba2
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1 Department of Electronics & Communication Engineering, Jain College of Engineering and Research, Visvesvaraya Technological University, Belagavi, Karnataka , India
2 Department of Electronics & Communication Engineering, Hirasugar Institute of Technology, Visvesvaraya Technological University, Belagavi, Karnataka , India
AIH, 026320107 https://doi.org/10.36922/AIH026320107
Received: 5 August 2026 | Revised: 3 September 2026 | Accepted: 15 September 2026 | Published online: 28 September 2026
© 2026 by the Author(s). This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution 4.0 International License ( https://creativecommons.org/licenses/by/4.0/ )
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Abstract

Structural retinal optical coherence tomography (OCT) markers of Alzheimer’s disease overlap with those of normal aging, which limits their diagnostic specificity. We investigate whether the light-dependent functional response of the retina can serve as a biomarker of Alzheimer’s disease that is largely independent of chronological age and propose a deep learning architecture that distinguishes the disease-related signal from the ageing-related signal. Using the publicly available Bissig functional OCT dataset of dark-adapted and light-adapted reflectance profiles from 38 subjects, we develop the Age-Debiased Retinal-response Attention Network (ADRA-Net), which encodes paired dark and light profiles through a shared fully-connected encoder, models the light response through a differential stream, applies depth attention, and enforces reduced age dependence through a gradient-reversal adversary. We primarily evaluate the model using strict subject-disjoint five-fold cross-validation, report 95% confidence intervals (CIs) across folds, and present the record-level protocol only as an optimistic reference for comparison with the literature. Under subject-disjoint validation ADRA-Net achieved a mean area under the curve of 0.72 (95% CI: 0.52–0.91), an accuracy of 73.2% (95% CI: 63.7%–82.7%) and a balanced accuracy of 67.9% (95% CI: 58.4%–77.3%); the record-level protocol, which allows scans of the same subject to appear in training and testing, gave an inflated area under the curve of 0.96 and accuracy of 94.1%, illustrating the effect of subject leakage. The gradient-reversal adversary reduced chronological-age decodability from the functional embedding to 52.7% under subject-disjoint testing, close to the 50% chance level, whereas structural features remained strongly age-predictive (87.9%). These proof-of-concept results provide evidence that the functional retinal response carries Alzheimer-related information with substantially reduced age dependence; however, validation in larger, multi-site cohorts is required before any clinical use.

Graphical abstract
Keywords
Alzheimer’s disease
Optical coherence tomography
Retinal biomarker
Age-invariant representation learning
Adversarial debiasing
Attention networks
Funding
None.
Conflict of interest
The authors declare that they have no conflicts of interest.
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Artificial Intelligence in Health, Electronic ISSN: 3029-2387 Print ISSN: 3041-0894, Published by AccScience Publishing
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