Abstract
Purpose :
We have developed a retinal prosthesis using suprachoroidal–transretinal stimulation (STS). However, the shape recognition of patients implanted with STS prosthesis has not yet been markedly improved. Therefore, a rehabilitation program such as that combining vision with tactile sensation is essential for improvising shape recognition. We examined the possibility of obtaining better shape recognition in subjects simulated with retinal prosthesis simulator (RPS) by vision learning associated with tactile sensation.
Methods :
Fourteen healthy subjects (men, 9; women, 5; age, 21–45 years) with left-eye occluded wore an RPS. Images were captured using a web camera attached to a head-mount display (HMD), processed by a computer, and displayed on HMD (7 × 7 dots; visual angle, 15°). We randomly presented one of five white targets that were in the shapes of B, E, K, R, and S (9 cm × 9 cm × 5 mm). They were made from polystyrene on a blackboard (40 × 60 cm). The subjects were instructed to look at the blackboard for 10 s with RPS and to identify the letters on the blackboard. This process was repeated 15 times (test). After the test, we randomly divided the subjects into two groups (n = 7 in each group) with different learning protocols; one group was instructed to touch letter-shaped targets made from polystyrene and was allowed to visualize the targets with RPS (cubic learning), whereas the other group was instructed to touch papers printed with white letters and was allowed to visualize the papers with RPS (paper learning). After learning, all subjects performed the above test again. This was followed by a comparison of correct answers of the tests between the two groups, both before and after learning.
Results :
The study showed no significant difference in the mean rates of correct answers between the two groups before learning (paper learning, 41.3 ± 14.0% vs. cubic learning, 39.1 ± 14.9%; Mann–Whitney test, p = 0.80); however, the mean rate after learning was higher in the cubic learning group than in the paper learning group (25.7 ± 13.5% vs. 64.7 ± 15.4%; p = 0.002).
Conclusions :
The vision learning associated with tactile sensation was effective in improving shape recognition and might be useful for the rehabilitation of patients implanted with retinal prosthesis.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.