Cone of Experience - Edgar Dale

Cone of Experience

Edgar Dale introduced this method of categorizing media's ability to communicate information in 1946. It basically states that learners must have sufficient real-life, concrete experiences to build upon for them to grasp more complex, less realistic and abstract concepts as they mature. For example, if children were to look at pictures of flowers and know what they were, they must have first seen, smelled and touched real flowers. 

Source: Wikipedia

In terms of distance education, it is possible to bring the sight and sound of an object, but it is not possible to bring the smell. It is important for new information to be presented as realistically as possible. (Simonson, Smaldino, & Zvacek, 2015, p. 81) This does not mean that "realistic" is better. In fact, realistic instruction has the potential to introduce "noise" that actually detracts the learner from possibly grasping a skill. It is important for instructional designer to consider the advantages and disadvantages of offering realistic instruction vs more abstract instruction. Failing to identify the best approach can be costly and jeopardize the overall goal of grasping a skill or concept. Sometimes the best approach is somewhere in the middle of the spectrum between concrete and abstract.

Source: Simonson, M. R., Smaldino, S. E., & Zvacek, S. (2015). Teaching and learning at a distance: Foundations of distance education (6th ed.).