# Smartphone Pupillometer for At-Home Screening for Risk of Alzheimer’s Disease

> **NIH NIH R21** · UNIVERSITY OF CALIFORNIA, SAN DIEGO · 2021 · $392,099

## Abstract

Project Summary/Abstract
Dementia represents one of the most important public health concerns in the coming decades. Among the most
important research goals will be to identify the earliest, most reliable and easily obtainable biomarkers of
degeneration, because early identification of individuals most likely to decline now represents the most promising
window for therapeutic interventions. The main objective of this project is to develop an Alzheimer’s disease
(AD) screening solution based completely on a smartphone application that converts the phone’s facial
recognition IR camera into a mobile pupillometer. Our scientific premise, demonstrated by our recent clinical
findings, is that pupillary responses provide a biomarker of cognitive effort required to perform tasks before overt
performance declines are manifest. Pupil size during cognitive tasks (e.g., digit span recall) increases in
response to increased demands, is inversely related to cognitive ability (individuals with lower ability show
greater dilation/compensatory effort), and pupil size decreases and performance declines when task demands
exceed abilities and compensatory capacity. Someone requiring more effort to achieve the same score as
another person is likely to be closer to maximum compensatory capacity and, therefore, at higher risk for decline.
We have found that individuals with mild cognitive impairment (MCI), who are at greater risk for AD, show greater
dilation (effort) on the digit span task, and that greater dilation is associated with greater polygenic risk for AD
and neuroimaging indicators of locus coeruleus (LC) dysfunction. This is important because pupillary responses
reflect LC functioning, and postmortem studies implicate the LC as an early site of AD pathogenesis and
degenerative changes with disease progression. Thus, pupillary responses may serve as a specific biomarker
of functional alterations in a brain system affected by the earliest manifestations of AD. Currently, pupillary
responses can be measured in as little as 5 minutes using minimally invasive, but expensive and complicated
office-based devices. To increase the scalability of pupillometry screening in AD, we propose to develop a
smartphone assessment that older adults can administer themselves at home that tracks small changes in pupil
dilation during cognitive tasks. We will further develop and evaluate different machine learning algorithms that
use the pupillary response biomarker measured by the phone to perform automated risk assessment of severity
of mild cognitive impairment at the early stages of AD. Because the project would be carried out in the context
of a larger NIA-funded RF1 affiliated with the UC San Diego Alzheimer’s Disease Research Center (ADRC), it
will be possible to validate mobile pupillometry assessments against gold-standard in-lab pupillometry in older
adults with MCI, early AD, and healthy controls. Our translational goal is to provide access to low-cost at-home
screenin...

## Key facts

- **NIH application ID:** 10214386
- **Project number:** 1R21AG072534-01
- **Recipient organization:** UNIVERSITY OF CALIFORNIA, SAN DIEGO
- **Principal Investigator:** Edward Jay Wang
- **Activity code:** R21 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2021
- **Award amount:** $392,099
- **Award type:** 1
- **Project period:** 2021-04-15 → 2024-03-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10214386

## Citation

> US National Institutes of Health, RePORTER application 10214386, Smartphone Pupillometer for At-Home Screening for Risk of Alzheimer’s Disease (1R21AG072534-01). Retrieved via AI Analytics 2026-05-23 from https://api.ai-analytics.org/grant/nih/10214386. Licensed CC0.

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