Learning from technical documents: the role of intermodal referring expressions.
We investigated the impact of two types of intermodal referring expressions on efficiency of instructions for use. User manuals for software or technical devices such as a video recording system frequently combine verbal instructions and illustrations. Much research has shown that the presence of an illustration has a beneficial effect on learning. The present study focuses on a factor that modulates this beneficial effect. The combination of text and an illustration can be effective only if the user integrates the information coming from these two media. This integration depends largely on the intermodal referential expressions, the function of which is to mark explicitly the relations between the text and the illustration. In an experiment (N = 104), we compared the effectiveness of two intermodal referring expressions often used in procedural texts: indexes (numbers introduced in the illustrations and in the instructions to establish cross-references) and icons (visual representations of the components of the device, which are inserted in the verbal instructions). The icons condition led to the most efficient use of the device. This experiment shows that learning from multimedia documents depends on the possibility of effectively connecting the verbal instructions to the illustration. Taking into account the ergonomic properties of the cross-media referring expressions should allow text designers to improve the effectiveness of technical documents.