Abstract
Purpose:
In our modern society, many touch screen applications require the eye-hand ability to associate a target or an icon with its specific contextual unit, on phones, computers, or in public transport. We investigate the ability of patients with bilateral glaucoma to use a touch screen to find, recognize, and associate an object to a consistent background scene.
Methods:
Twelve patients (age range, 60-82 years) with a stable bilateral primary open angle glaucoma (visual acuity of 4/10 or better in each eye), 12 age-matched (age range, 60-94 years) and 12 young (age range, 22-34 years) participants with normal visual acuity (>8/10) were recruited.<br /> The participants had to associate, by moving their index on a 22” touch screen, a target (an animal or an object) on the unique scene (between three other distractor images) with a consistent background related to the target (e.g. to match a fish with the sea, or a mug with the kitchen).<br /> We recorded the accuracy of the responses, the total time to achieve the task, the exploration duration, and movement parameters such as the movement duration, the peak speed (time and velocity), the deviation of the movement, the ratio between the time to peak and the movement duration which gives information about the appearance of the deceleration phase.
Results:
Patients with glaucoma were slower than age-matched control and young participants to explore the scenes and to initiate the movement. None of the movement parameters recorded in this study was affected by the visual field loss. Nevertheless, the older participants (patients and control) were impaired on two movement parameters. Their peak speed decreased (-8 cm/s) and their movement duration increased (+0.9 sec) with age compared to the young group.
Conclusions:
This study shows that people with glaucoma are able to perform a contextual association task on a large touch screen. These findings are important in our modern society depending more and more of numeric and touch screen applications (phones, public transport information, e-drive shopping…). Icons, targets, are usually very small on phones, tablets and, patients cannot recognize it. Some new applications could be created by using picture and contextual association to help patients with vision loss.