Abstract

Two experiments extended psychophysical methods of the theory of signal detectability (TSD) to the study of the temporal discrimination of brief two-pulse visual stimuli. Experiment I tested the TSD prediction that observer sensitivity is independent of the psychophysical method used in measurement. Discrimination between a constant-duration (interpulse interval) comparison stimulus (3 ms) and a variable-duration test stimulus (7–32 ms) was measured with a two-alternative forced-choice (FC) procedure and a “yes–no” procedure. Sensitivity was comparable under the two psychophysical procedures, thus supporting the application of TSD in future studies of the sensory processes involved in discrimination of two-pulse stimuli. Experiment II measured discrimination with the FC procedure at three luminance levels: 31.8, 318, and 3183 cd/m². Discriminability increased with luminance. This significant luminance effect is in agreement with the previous findings of Lewis and Mertens concerning the effect of luminance variation in the photopic range on two-pulse thresholds.

© 1972 Optical Society of America

Two-Pulse Measures of Temporal Resolution as a Function of Stimulus Energy*

Mitchell L. Kietzman
J. Opt. Soc. Am. 57(6) 809-813 (1967)

Psychophysical Responses to Homochromatic Stimuli of Equal Brightness but Unequal Luminance*

Judith Wheeler Onley and Charles E. Sternheim
J. Opt. Soc. Am. 57(2) 258-267 (1967)

Luminance, not brightness, determines temporal brightness enhancement with chromatic stimuli

Richard W. Bowen and Mary Jo Nissen
J. Opt. Soc. Am. 69(4) 581-584 (1979)

Temporal Summation during Dark Adaptation*

Barbara R. Stewart
J. Opt. Soc. Am. 62(3) 449-457 (1972)

Visual Latency as a Function of Stimulus Onset, Offset, and Background Luminance*

Ralph W. Hansteen
J. Opt. Soc. Am. 61(9) 1190-1195 (1971)