Behavioral measurements of rat spectral sensitivity

Abstract

Behavioral measurements of visual sensitivity were obtained from hooded rats on a threechoice discrimination task. Increment threshold measurements reveal the occurrence of a distinct Purkinje shift. Photopic spectral sensitivity functions for this animal have peaks at 500 and 580 nm. The results of chromatic adaptation suggest that this photopic sensitivity function results from interactions between two mechanisms with peak sensitivities near 520 and 540 nm. Along with previous behavioral and electrophysiological results, these findings suggest that the rat possesses at least three different spectral mechanisms—a scotopic mechanism with a peak sensitivity at 500 nm and two photopic mechanisms whose peak sensitivities may be about 520 and 540 nm.