Successive processing of color and form from brief visual displays.

Visual processing of multidimensional stimuli was explored with a task designed to determine the number of separable perceptual stages operating and the nature of their relationship. Displays containing 2 rows of 5 randomly selected letters were presented briefly. In half the displays, 1 of the 10 letters was red and the other 9 black; in the remaining displays, all 10 letters were black. Ss made two responses to each display; color detection, in which the presence or absence of a red letter was judged, and letter naming, in which Ss reported as many letters as they could. The findings suggested that the two tasks were performed by separate perceptual mechanisms and the selection of letters to be named could be influenced by the information acquired by the color-detection mechanism.