Abstract

Steady-state evoked potentials were recorded from the human scalp and subjected to Fourier analysis during the psychophysical procedure of heterochromatic flicker photometry. The amplitudes of harmonic components whose frequencies fell in the range roughly 45–55 cps showed a clear minimum. This minimum coincided with the point of minimum subjective flicker. This agreement did not generally hold either for harmonic components in the range 13–22 cps nor for the peak-to-peak amplitude of the averaged evoked potential. Relative spectral-sensitivity curves derived both from psychophysical and evoked-potential data agreed within 0.07 log units (18%). The objective method described below is considerably more precise, and is less affected by evoked-potential variability, than previous methods that used evoked-potential amplitude to measure spectral sensitivity. A complete spectral-sensitivity curve can be obtained in two sessions of $2\frac{1}{2}\hspace{0.17em}\text{h}$ each, and the procedure could probably be shortened significantly.

© 1970 Optical Society of America

Luminosity and CFF in Deuteranopes and Protanopes*

Joel Pokorny and Vivianne C. Smith
J. Opt. Soc. Am. 62(1) 111-117 (1972)

Psychophysical Spectral-Sensitivity Measurements and Color-Matching Data*

Sheldon Miller
J. Opt. Soc. Am. 60(10) 1404-1406 (1970)

Flicker Sensitivity and Apparent Brightness as a Function of Surround Luminance*

Lewis O. Harvey
J. Opt. Soc. Am. 60(6) 860-864 (1970)

Visual Masking by Low-Frequency Sinusoidally Modulated Light

G. M. SHICKMAN
J. Opt. Soc. Am. 60(1) 107-117 (1970)

Some Comparisons between Foveal Spectral Sensitivity Data Obtained at High Brightness and Absolute Threshold

H. G. Sperling and W. G. Lewis
J. Opt. Soc. Am. 49(10) 983-989 (1959)