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Heading perception in patients with advanced retinitis pigmentosaPURPOSE: We investigated whether retinis pigmentosa (RP) patients with residual visual field of < 100 degrees could perceive heading from optic flow. METHODS: Four RP patients and four age-matched normally sighted control subjects viewed displays simulating an observer walking over a ground. In experiment 1, subjects viewed either the entire display with free fixation (full-field condition) or through an aperture with a fixation point at the center (aperture condition). In experiment 2, patients viewed displays of different durations. RESULTS: RP patients' performance was comparable to that of the age-matched control subjects: heading judgment was better in the full-field condition than in the aperture condition. Increasing display duration from 0.5 s to 1 s improved patients' heading performance, but giving them more time (3 s) to gather more visual information did not consistently further improve their performance. CONCLUSIONS: RP patients use active scanning eye movements to compensate for their visual field loss in heading perception; they might be able to gather sufficient optic flow information for heading perception in about 1 s.
Document ID
20040088096
Document Type
Reprint (Version printed in journal)
Authors
Li, Li (The Schepens Eye Research Institute, Harvard Medical School Boston, Massachusetts 02114, United States)
Peli, Eli
Warren, William H.
Date Acquired
August 21, 2013
Publication Date
September 1, 2002
Publication Information
Publication: Optometry and vision science : official publication of the American Academy of Optometry
Volume: 79
Issue: 9
ISSN: 1040-5488
Subject Category
Life Sciences (General)
Funding Number(s)
CONTRACT_GRANT: EY10285
CONTRACT_GRANT: EY10923
CONTRACT_GRANT: EY12890
Distribution Limits
Public
Copyright
Other