This paper introduces and gives a report of the first of a series of studies concerned with the developmental aspects of information processing. The experiments are concerned chiefly with how repeated visual encounters influence infants' attentional preference for what is familiar or unfamiliar and how infants' preference can be affected by responsiveness to the infants' spontaneous efforts. In the first exploratory study of the series, two stimulus patterns were placed over the cribs of 15 infants for the infants to look at and be familiar with. One pattern was stationary and one moved. Following 4 to 5 weeks of exposure, each baby's preference for one of the patterns was assessed. Next, each of the familiar patterns was presented simultaneously with an unfamiliar one and then reversed, and a record of the direction of the infant's gaze was kept. Results favored the hypothesis of attentional preference for the familiar pattern. The general strategy used in this study is to be further refined in the author's subsequent studies. (DR)