15.8  Conclusion

With the wide range of research that is currently underway to develop a visual prosthesis it is possible that we will see several groups implanting humans in the next 5 years.

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Part IV

Towards Prosthetic Vision: Simulation,

Assessment, Rehabilitation

Chapter 16

Simulations of Prosthetic Vision

Michael P. Barry and Gislin Dagnelie

Abstract  Simulations of prosthetic vision can provide requirements and ­specifications for prosthesis designs and stimulus conditions; these requirements are expected to differ according to the visual task. Studies reviewed here include examinations of visual acuity, reading, face and object recognition, hand–eye coordination, way finding, visual tracking, and simple design feasibility. Based on these studies, visual acuity with prosthetic vision seems to depend most on the resolution of perceived phosphenes. Given usable visual acuity, all visual tasks that have been evaluated in simulations with variable dot counts demonstrate some significant dependence on the number simulated phosphenes provided. Some tasks also have more unique dependencies: Facial recognition seems quite sensitive to the number of gray levels and the relative size of dots and spacing. Wayfinding is most dependent on the angle of view captured by the camera. In many of the simulation studies practice was found to be an important factor for successful task performance. As visual prosthesis development becomes less limited by technological barriers, findings from simulation studies may become increasingly important for the design of implants and rehabilitation programs.

Abbreviations

´Symbol for minutes of arc

M.P. Barry (*)

Lions Vision Research and Rehabilitation Center, Wilmer Eye Institute, Johns Hopkins University School of Medicine, 550 N. Broadway, 6th Floor, Baltimore, MD 21205, USA e-mail: mbarry11@jhu.edu