The cognitive consequences of modality assignment for educational communication: the picture in logic teaching

This paper describes a semantic approach to understanding the cognitive consequences for educational communication of assigning the same information to different modalities. The central idea is to base a theory of usability on semantic analysis of representational systems, and in particular the consequences of semantics for the computational complexity of reasoning. The paper reviews published work on evaluating interactive multi-media logic teaching as a test of the framework. One comparison is between sentential and graphical representations in teaching first-order logic (Stenning, Cox & Oberlander, 1995). This comparison reveals substantial aptitude×treatment interactions which hinge on the semantic issues predicted to be pivotal in determining usefulness. Another comparison is between alternative graphical methods of teaching (Dobson, 1995). The example studies illustrate the benefits and problems in applying a semantic analysis to representations used in education.