The Influence of Subject Expectation on Visual Accommodation in the Dark,
Abstract
The prospect of a pilots vision at night being reduced to a less than optimal state by night myopia has been debated for years in a large body of research. This report casts doubt on the existence of night myopia in young healthy pilots by presenting evidence that the accommodative relfex may be driven by direct cognitive control inputs. Direct cognitive control, based on an individual's expectation of accommodative range, could bias measures of night myopia if the measuring instruments are placed close to the subject's eyes. Subjects studied for this report demonstrated excellent visual performance in the dark, at a range of 20 ft, despite measured night myopia of up to 7.94 diopters.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1991
- Accession Number
- ADA245923
Entities
People
- W. B. Cushman
Organizations
- Naval Aerospace Medical Research Laboratory