Discrete and continuous linear models are defined to describe contrast phenomena such as Mach bands. Two-sided z transforms are used to describe the discrete systems and Fourier transforms are used to describe continuous systems. A <i>psychological</i> model is defined based on the work of v. Békésy on skin and vision which suggests a "neural unit" consisting of an area of sensation surrounded by an area of inhibition. A <i>physiological</i> model is also defined based on the experiments of Hartline <i>et al</i>., describing lateral neural interaction in the eye of <i>Limulus</i>. It is shown that the <i>physiological</i> model is related to the <i>psychological</i> model and that the form of the physiological inhibitory coefficients <i>k<sub>p</sub></i> uniquely specify the form of the psychological neural unit <i>h<sub>p</sub></i>, and vice versa. Also, by assuming a "blurring" of the stimulus spatial distribution as the excitation distribution of the receptors, a neural unit is obtained from the <i>physiological</i> model which is similar to the psychological neural unit suggested by the experiments of v. Békésy. Illustrative examples are given.
JAMES C. BLISS and WILLIAM B. MACURDY, "Linear Models for Contrast Phenomena," J. Opt. Soc. Am. 51, 1373-1379 (1961)