# AI-Driven Prediction of Possible Mild Cognitive Impairment Using the Oculo-Cognitive Addition Test (OCAT)

## TL;DR

This paper introduces an AI-powered eye-tracking test called OCAT that can quickly and accurately predict mild cognitive impairment, potentially enabling early diagnosis and reducing the need for lengthy cognitive exams.

## Contribution

The study introduces a novel AI-driven approach using OCAT's oculometric features to predict MCI with high accuracy, offering a scalable and rapid screening method.

## Key findings

- Combined time and eye movement features in logistic regression models achieved 97% accuracy in predicting MCI.
- OCAT-based models outperformed models using only time or eye movement features alone.
- The approach shows potential for practical use in clinics and remote settings.

## Abstract

Background/Objectives: Mild cognitive impairment (MCI) affects multiple functional and cognitive domains, rendering it challenging to diagnose. Brief mental status exams are insensitive while detailed neuropsychological testing is time-consuming and presents accessibility issues. By contrast, the Oculo-Cognitive Addition Test (OCAT) is a rapid, objective tool that measures oculometric features during mental addition tasks under one minute. This study aims to develop artificial intelligence (AI)-derived predictive models using OCAT eye movement and time-based features for the early detection of those at risk for MCI, requiring more thorough assessment. Methods: The OCAT with integrated eye tracking was completed by 250 patients at the Mayo Clinic Arizona Department of Neurology. Raw gaze data analysis yielded time-related and eye movement features. Random Forest and univariate decision trees were the feature selection methods used to identify predictors of Dementia Rating Scale (DRS) outcomes. Logistic regression (LR) and K-nearest neighbors (KNN) supervised models were trained to classify PMCI using three feature sets: time-only, eye-only, and combined. Results: LR models achieved the highest performance using the combined time and eye movement features, with an accuracy of 0.97, recall of 0.91, and an AUPRC of 0.95. The eye-only and time-only LR models also performed well (accuracy = 0.93), though with slightly lower F1-scores (0.87 and 0.86, respectively). Overall, models leveraging both time and eye movement features consistently outperformed those using individual feature sets. Conclusions: Machine learning models trained on OCAT-derived features can reliably predict DRS outcomes (PASS/FAIL), offering a promising approach for early MCI identification. With further refinement, OCAT has the potential to serve as a practical and scalable cognitive screening tool, suitable for use in clinics, at the bedside, or in remote and resource-limited settings.