| Problem solving has been shown to benefit from the ability to perceive structure in a novel problem. Strong structural understanding is an indication of well developed mental models. Two commonly used instructional methods, graphic illustrations and verbal analogies, have the ability to communicate structure but do so using different cognitive processes. Either method used separately, has proven to increase problem solving transfer, especially with novices. This study explored the possible synergy of instructional illustrations and analogies by attempting to answer the following and related research questions. Do illustrations and analogies work together to promote useful mental models as measured by problem solving transfer or conceptual inference problems? Subjects judged as novices in the subject of the Internet, were randomly assigned to one of four instructional treatments. The design was a 2 (no illustration, illustration) x 2 (no analogy, analogy) analysis of variance. Subjects who received both illustration and analogy did not score the highest on problem solving and conceptual inference measures as expected. The (illustration, no analogy) group scored significantly higher than all other groups; followed by both analogy groups (illustration, analogy) and (no illustration, analogy); followed by the control (no illustration, no analogy). The results of this study suggest that presenting an illustration and analogy together induces a processing or information overload condition which hinders mental model construction. It also suggests that the processing of a graphical illustration dominates the processing of a verbal analogy when presented together. It is the conclusion of this study that illustrations and analogies, while effective separately, interfere with mental model construction when used simultaneously. Instruction should strive to avoid processing overload. |
