Visual and Computational Teaching and Learning

Traditionally, in technical expository writing, illustrations are treated as adjuncts to the text where the reader is referred to the illustrations by the text which describes or explains the illustration rather than being tightly integrated into the narrative. Recent research in cognitive psychology is producing a new set of guidelines that define how to effectively use illustrations. Based on this research we know that cognitive load is reduced when illustrations are integrated into the text (contiguity principle); extraneous or irrelevant material should be removed from illustrations (coherence principle); multiple representations that engage different parts of the brain improve learning (modality effect); and, use of repetition improves encoding accuracy and transfer to long-term memory (redundancy principle). Using appropriate levels of abstraction and goal free presentations also reduce cognitive load. With a few notable exceptions, the traditional approach often conflicts with what we now believe to be the best ways to effectively use illustrations. This can be a particular problem in computer science where attention may be split among text, code, and illustrations. It is possible to develop a visual narrative style that embodies the principles from cognitive psychology. In fact, this has been done informally for centuries (e.g., da Vinci’s notebooks), but the approach is still rarely used in formal writing or in published materials. With recent technological developments, such as page layout software and digital ink, the process has been simplified and is now growing in popularity. This paper reviews the cognitive basis for effectively using illustrations in mathematics and computer science.