March 2012
Volume 53, Issue 14
Free
ARVO Annual Meeting Abstract  |   March 2012
Mobility Experiments Using Simulated Prosthetic Vision With 98 Phosphenes Of Limited Dynamic Range
Author Affiliations & Notes
  • Paulette Lieby
    Canberra Research Laboratory, NICTA, Canberra, Australia
    Engineering,
    The Australian National University, Canberra, Australia
  • Nick Barnes
    Canberra Research Laboratory, NICTA, Canberra, Australia
    Engineering,
    The Australian National University, Canberra, Australia
  • Chris McCarthy
    Canberra Research Laboratory, NICTA, Canberra, Australia
    Engineering,
    The Australian National University, Canberra, Australia
  • Adele F. Scott
    Canberra Research Laboratory, NICTA, Canberra, Australia
  • Viorica Botea
    Canberra Research Laboratory, NICTA, Canberra, Australia
  • Janine G. Walker
    Canberra Research Laboratory, NICTA, Canberra, Australia
    Centre for Mental Health Research,
    The Australian National University, Canberra, Australia
  • Footnotes
    Commercial Relationships  Paulette Lieby, None; Nick Barnes, WO/2011/041842 (P); Chris McCarthy, None; Adele F. Scott, None; Viorica Botea, None; Janine G. Walker, None
  • Footnotes
    Support  Bionic Vision Australia (ARC SRI on Bionic Vision Science and Technology), NICTA (DBCDE, Australian Govt, and ARC), NH&MRC Capacity Building Grant #418020
Investigative Ophthalmology & Visual Science March 2012, Vol.53, 5539. doi:
  • Views
  • Share
  • Tools
    • Alerts
      ×
      This feature is available to authenticated users only.
      Sign In or Create an Account ×
    • Get Citation

      Paulette Lieby, Nick Barnes, Chris McCarthy, Adele F. Scott, Viorica Botea, Janine G. Walker; Mobility Experiments Using Simulated Prosthetic Vision With 98 Phosphenes Of Limited Dynamic Range. Invest. Ophthalmol. Vis. Sci. 2012;53(14):5539.

      Download citation file:


      © ARVO (1962-2015); The Authors (2016-present)

      ×
  • Supplements
Abstract

Purpose: : Using simulated prosthetic vision (SPV) and a mobility course including overhanging obstacles, we evaluate the effectiveness of a 98 phosphenes, low dynamic range retinal implant. (Bionic Vision Australia's first prototype retinal prosthesis will have 98 electrodes). Effectiveness was defined as a percentage of preferred walking speed (PPWS) larger than 50%.We investigated the performance of two visual representations: Intensity (visual field luminance); and, Depth (relative depth of the visual field). Depth provides an example of an alternative visual representation that is robust to low contrast environments.

Methods: : Four normally-sighted participants (20/20, Pelli-Robson>=1.95) traversed a mobility course using mobile SPV showing 98 phosphenes on a hexagonal grid and centrally displayed identically to both eyes. Each phosphene was rendered over 8 levels of brightness. The study had a double-blind randomised factorial

Results: : In the test phase, mean PPWS for both Intensity (n=56) and Depth (n=110) was significantly larger than 50% (p<=0.028). For both Intensity and Depth, mean PPWS was significantly greater in the test phase compared to the training phase (p<=0.035); indicating that participants became more adept to both visual representations over time. Across all sessions, Intensity (n=104, mean PPWS=61%) and Depth (n=204, mean PPWS=50%) had significantly higher PPWS than no meaningful visual information (n=19, mean PPWS=27%, p<0.001). Intensity had significantly higher mean PPWS than Depth (p<0.001).

Conclusions: : Visual information representing scene contrast or depth cues using simulated prosthetic vision showing 98 phosphenes under low dynamic range conditions may be used for effective mobility.

Keywords: image processing • space and scene perception 
×
×

This PDF is available to Subscribers Only

Sign in or purchase a subscription to access this content. ×

You must be signed into an individual account to use this feature.

×