Alesandrini, K. L. (1984). Pictures and adult learning. Instructional Science, 13, 63 - 77.

Abstract. Instructional pictures may be classified on the basis of how they convey meaning including classification as representational, analogical, or arbitrary (Gropper, 1963; Knowlton, 1966). Some previous reviews of picture effects have dealt with only the first category of pictures - that is, pictures that are isomorphic with the objects or concepts that they represent (Alesandrini, 1982; Levin and Lesgold, 1978). Other reviews have also considered arbitrary or non-representational pictures such as flowcharts and graphs (Levie and Lentz, 1982; Macdonald-Ross, 1977a). This article discusses research on all three types of pictures and considers how each type may play a crucial, yet different, role in the learning process. The focus is on picture effects in adult meaningful learning such as concept learning, learning from prose materials, and learning from expository text.
Summary. The results of the studies discussed in this article suggest that all three types of pictures - representational, analogical, and arbitrary - deserve attention by practitioners as ways to communicate information and facilitate learning. A small but convincing core of studies has demonstrated that all three types can facilitate learning. Further research is neeeded to identify how each type can be used most effectively during the learning process. The following possibility is suggested by the research and deserves further study: a) begin with analogical pictures to relate new information to prior knowledge, b) follow with arbitrary pictures to convey the essence of the new information and distinguish it from the analogous information, and c) conclude with representational pictures that serve to further define and distinguish the new information.