The performance of 16 male observers who searched for an incomplete ring (Landolt C) among a number of solid rings in a square, moving field was measured. Search performance deteriorated as velocity or object density was increased; a target was more likely to be detected the closer it was to the center of the field; there was no significant correlation between the age of the observer and his search performance; there was significant correlation between foveal visual acuity and search performance in the moving field. The performance of the same observers on a previous series of tests is compared to their performance on the tests reported here. A hypothesis concerning the role of peripheral and foveal vision in searching for targets is advanced.
RONALD A. ERICKSON, "Visual Search Performance in a Moving Structured Field," J. Opt. Soc. Am. 54, 399-403 (1964)