Abstract:
Humans are beyond all visual beings since most of the outside information is gathered through the visual system. When the aging process starts, visual functional damages become more and more common and the risk of developing visual impairment is higher. Age-related macular degeneration (AMD) is one of the main afflictions that leads to severe damage to the optical system due to the aging process. The ones affected lose the ability to use the central part of vision, essential for accurate visual information processing.
Even if less accurate, peripheral vision remains unaffected, hence medical experts have developed training procedures to train patients to use peripheral vision instead to navigate their environment and continue their daily lives. This type of training is called eccentric viewing. However, there are several shortcomings in current approaches, such as not being engaging or individualizable enough nor cost and time-effective.
The main scope of this dissertation was to find out if more engaging and individualizable methods can be used for peripheral training of AMD patients. The current work used virtual reality (VR) gaming to deliver AMD training; the first time such an approach was used for eccentric viewing training. In combination with eye-tracking, real-time individualized assistance was also achieved. Thanks to an integrated eye-tracker in the headset, concentric gaze-contingent stimuli were used to redirect the eyes toward an eccentric location. The concentric feature allowed participants to choose freely and individually their peripheral focus point.
One study investigated the feasibility a VR system for individualized visual training of ophthalmic patients, two studies investigated two types of peripheral stimuli (three spatial cues and two optical distortions) and the last study was a case study looking into the feasibility of such an approach for a patient with late AMD.
Changes in gaze directionality were observed in all the last three studies for one specific spatial cue, a concentric ring. In accordance with the literature, the gaze was directed spontaneously toward the most effective peripheral position. The last study additionally proved gaming feasible for future testing of the elderly AMD population. The current work opened the road to more individualized and engaging interventions for eccentric viewing training for late AMD.