Facial Recognition Using Simulated Prosthetic Pixelized Vision

Robert W. Thompson, G. David Barnett, Mark S. Humayun, Gislin Dagnelie

Research output: Contribution to journalArticle

Abstract

PURPOSE. To evaluate a model of simulated pixelized prosthetic vision using noncontiguous circular phosphenes, to test the effects of phosphene and grid parameters on facial recognition. METHODS. A video headset was used to view a reference set of four faces, followed by a partially averted image of one of those faces viewed through a square pixelizing grid that contained 10 × 10 to 32 × 32 dots separated by gaps. The grid size, dot size, gap width, dot dropout rate, and gray-scale resolution were varied separately about a standard test condition, for a total of 16 conditions. All tests were first performed at 99% contrast and then repeated at 12.5% contrast. RESULTS. Discrimination speed and performance were influenced by all stimulus parameters. The subjects achieved highly significant facial recognition accuracy for all high-contrast tests except for grids with 70% random dot dropout and two gray levels. In low-contrast tests, significant facial recognition accuracy was achieved for all but the most adverse grid parameters: total grid area less than 17% of the target image, 70% dropout, four or fewer gray levels, and a gap of 40.5 arcmin. For difficult test conditions, a pronounced learning effect was noticed during high-contrast trials, and a more subtle practice effect on timing was evident during subsequent low-contrast trials. CONCLUSIONS. These findings suggest that reliable face recognition with crude pixelized grids can be learned and may be possible, even with a crude visual prosthesis.

Original languageEnglish (US)
Pages (from-to)5035-5042
Number of pages8
JournalInvestigative Ophthalmology and Visual Science
Volume44
Issue number11
DOIs
StatePublished - Nov 2003

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Phosphenes
Visual Prosthesis
Learning
Facial Recognition

ASJC Scopus subject areas

  • Ophthalmology

Cite this

Facial Recognition Using Simulated Prosthetic Pixelized Vision. / Thompson, Robert W.; Barnett, G. David; Humayun, Mark S.; Dagnelie, Gislin.

In: Investigative Ophthalmology and Visual Science, Vol. 44, No. 11, 11.2003, p. 5035-5042.

Research output: Contribution to journalArticle

Thompson, Robert W. ; Barnett, G. David ; Humayun, Mark S. ; Dagnelie, Gislin. / Facial Recognition Using Simulated Prosthetic Pixelized Vision. In: Investigative Ophthalmology and Visual Science. 2003 ; Vol. 44, No. 11. pp. 5035-5042.
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