Increment thresholds against pulsed and steady backgrounds

Research paper by Leonard Matin, Alan Kornheiser

Indexed on: 01 Jul '76Published on: 01 Jul '76Published in: Perception & psychophysics


Cornsweet and Pinsker reported that ΔL/L was constant at all values of L for briefly pulsed fields (ΔL was the luminance increment required for discriminating which of two nearby flashed fields was brighter). We obtain the same result when the subject must detect which of two briefly (4-msec) flashed backgrounds contains an increment at its center. However, when the background and increment are flashed at a longer duration (200 msec) ΔL/L decreases with increasing L as is obtained with a steady background. Two previous models which handle earlier work do not readily accommodate this result; we suggest a theoretical approach that does.