The experiment was designed to test differential predictions derived form dual-coding and depth-of-processing hypotheses. Subjects under incidental memory instructions free recalled a list of 36 test events , each presented twice. Within the list , an equal number of events were assigned to structural phonemic, and semantic processig conditions. Separate groups of subjects were tested with a list of pictures, concrete words, or abstract words. Results indicated that retention of concrete words increased as a direct function of the processig-task variable (structural<phonemic<semantic). However, for both abstract words and pictures, phonemic and semantic processing produced equivalent memory performance. These data provided strong support for the dual-coding model.