Interest and Feasibility of the DIGItracking Technique for the Early Diagnosis of COGnitive Disorders

Methods for cognitive decline diagnosis in elderly patients using simple, fun and ecological tests remain a major health issue. The objective is the early diagnosis of disorders in order to offer quick management of the decline of cognitive functions.

Eye tracking is a proven technique to study perceptual and cognitive functions in children and adults. It has recently been highlighted that it was also relevant to analyze the perceptual and cognitive functions of elderly people at different stages of neurocognitive disorders. Although very precise, this technique remains restrictive since it requires expensive equipment, technical skills, and long and repetitive tests while the patient stays motionless.

A new approach using the digit-tracking, named Digitrack (Lio et al. 2019), has shown excellent correlation with the eye tracking. The general principle is as follows: a blurred image is displayed on a touchpad screen. This degraded image reproduces the spatial resolution of the peripheral retina. While the patient put his finger on the screen, the area around the finger is unblurred, simulating the foveal region (central region) of the eye. By sliding his finger, the subject moves the unblurred window and can explore the image. The exploration trajectory, like the eye movement trajectory with eye tracking, is recorded and reveals the subjective regions of interest contained in the image which help to assess the user's neurocognitive functions.

The advantage of the Digitrack process is to require a cheap and easy-to-use device to assess the cognitive status of patients in a fun way and close to real conditions.

To date, its usability has not been demonstrated in elderly patients with or without neurocognitive disorders.

The investigators formulate the main hypothesis that patients visiting or hospitalized in the acute care geriatrics department, with or without cognitive disorders, can use the Digitrack process.

Inclusion criteria

• Men or women ≥ 75 years old
• Consultation or hospitalization in geriatrics department
• Subjects who can give written consent to participate in the study

Exclusion criteria

• Photosensitive epilepsy
• Uncorrected visual deficiency
• Any significative impairment at the upper limb level preventing from manipulating the device
• Persons deprived of their liberty by administrative or judicial decision, persons under psychiatric care under duress, adults subject to a legal protection measure or unable to express their consent