Accession Number : ADA187715

Title :   Visual Contrast Sensitivity Functions Obtained from Untrained Observers Using Tracking and Staircase Procedures.

Descriptive Note : Final technical rept. Oct 85-Apr 87,

Corporate Author : DAYTON UNIV OH RESEARCH INST

Personal Author(s) : Geri, George A ; Hubbard, David C

PDF Url : ADA187715

Report Date : Nov 1987

Pagination or Media Count : 26

Abstract : Two adaptive psychophysical procedures (tracking and yes-no staircase) for obtaining human contrast sensitivity functions (CSFs) were evaluated. The procedures were chosen based on their proven validity and our desire to evaluate the practical effects of stimulus transients, since tracking procedures traditionally employ gradual stimulus onsets whereas staircase procedures traditionally employ rapid stimulus onsets. The criteria for deciding which procedure was preferable for the rapid testing of large groups of untrained observers were consistency in the form of the measured CSFs across days, the subjective ease of the as judged by the observer, and the time required to obtain consistent results. Both procedures gave repeatable results across days; thus, the first CSF obtained from each subject could be taken as representative of the true CSF as determined by additional testing. However, the tracking procedure was judged easier to use by the present observers and required less time to perform. No interaction was found between any of these variables and the different stimulus onset parameters of the two procedures. Keywords: Visual acuity, Spatial distribution.

Descriptors :   *CONTRAST, *PSYCHOPHYSICS, *SPATIAL DISTRIBUTION, *STIMULI, *VISUAL PERCEPTION, ACCELERATED TESTING, ADAPTIVE SYSTEMS, CONSISTENCY, HUMANS, OBSERVERS, REPRODUCIBILITY, SENSITIVITY, TRACKING, TRAINING, TRANSIENTS, VISION, VISUAL PERCEPTION, VISUAL ACUITY

Subject Categories : Anatomy and Physiology
      Psychology

Distribution Statement : APPROVED FOR PUBLIC RELEASE