Three groups of 3 1/2-month-old infants were presented with varying and repeated exposures of visual stimili. For each group a different checkerboard pattern, i.e., 2x2, 12 x 12, or 24 x 24, served as the repeated stimulus. Visual fixation of each pattern declined significantly both during repetition and upon subsequent reexposure, the amount varying inversely with the complexity of the stimulus. In addition, infant girls showed steeper decrements than boys. © 1969, Psychonomic Journals, Inc.. All rights reserved.