The Impact of External Representations on Providing Online Instructions

In the following paper, we report on two studies which test for possible detrimental effects of external representations in a scenario where experts respond to email inquiries in medical advice. Based on research on expert-layperson-communication we assume that experts’ extensive and highly integrated knowledge of their own domain makes it very difficult for them to comprehend the completely different perspective of a layperson. Such an immersion into one’s own, privileged knowledge is exacerbated through the availability of external representations (e.g. diagrams of body functions). We hypothesize that especially visualizations which make the subject matter immediately evident for the expert, have such a detrimental effect. Varying the complexity of an external representation, only available to the expert, we established furthermore that an “easier”, that is, a less complex illustration, produces less audience-designed answers than a much more demanding and complex illustration.