Abstract
Two-flash thresholds were obtained from three dark-adapted Ss by means of a two-interval, temporal forced-choice technique involving foveally fixated circular targets varying in luminance and area. The Ss were instructed to report the temporal position of the longer of two pairs of I-msec flashes. a comparison pair with an interflash interval of 1 msec, and a test pair with a varying interflasn interval. The Ss were informed about the accuracy of their responses after each response. For all three Ss the results replicated a previous finding that two-flash thresholds are a negatively accelerated function of flash luminance. but the function was shown to be dependent on area. a greater threshold change occurring at smaller areas. Two-flash thresholds were also found to be a decreasing function of stimulus area. with the greatest threshold change occurring at low luminances.
Article PDF
Similar content being viewed by others
Avoid common mistakes on your manuscript.
References
BAUMGARDT, E., & LULLMAN, B. Duration and size as determinants of peripheral retinal response.J Opt. Soc. Amer., 1961, 51, 340–344.
CAMPBELL, R. A. Detection of a noise signal of varying duration.J. Acoust. Soc. Amer., 1963, 35, 1732–1737.
CORNSWEET, T. N. The staircase-method in psychophysics.Amer. J. Psychol., 1965, 75, 485–491.
GRAHAM, C. H., & MARGARJA, R. Area and the intensity-time relation in the peripheral retina:Amer. J. Physiol., 1935, 113, 299–305.
HECHT, S., & VERRIJP, C. D. Intermittent stimulation by light. III. and IV.J. gen Physiol, 1933, 17, 251–286.
KIETZMAN, M. L. Two-pulse measures of temporal resolution as a function of stimulusenergy.J. Opt. Soc. Amer., 1967, 57, 809–813.
LEWIS, M. F. Category judgments as functions of flash luminance and duration.J. Opt. Soc. Amer., 1965, 55, 1655–1660.
LEWIS, M. F. Two-flash thresholds as a function of luminance in the dark-adapted eye.J. Opt. Soc. Amer., 1967, 57, 814–815.
MAHNEKE, A. Fusion thresholds of the human eye as measured with two or several light flashes.Acta Ophthalmol., 1958, 36, 12–18.
PIÉRON, H. Vision in intermittent light. In W. D. Neff (Ed.),Contributions to sensory physiology, Vol. 1. New York: Academic Press, 1965, 179–264.
SPERLING, H. G., & JOLIFFE, C. L. Intensity-time relationship at threshold for spectral stimuli in human vision.J. Opt. Soc. Amer., 1965, 55, 191–199.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Lewis, M.F. Two-flash thresholds as a function of flash luminance and area. Perception & Psychophysics 4, 241–244 (1968). https://doi.org/10.3758/BF03206310
Accepted:
Issue Date:
DOI: https://doi.org/10.3758/BF03206310