Visual Information and Language Information
Information from text and speech is advantageous in conveying abstract concepts and for qualifying specific conditions. Imagery is often best for dealing with spatial and relational information. In addition, the amount of detail that may be included in an image is vast.
As the saying goes, "A picture is worth a thousand words." The logic may follow that if a picture is worth a thousand words, then a one-minute video at 30 frames per second is worth 1.8 million words. This cliche may provide one starting point for a discussion about the use of images and animations in teaching and learning.
It may be impossible to state the value of an image in terms of the number of words it represents. Paivio's dual coding theory suggests that visual information and language information are fundamentally different, and are stored in the memory as different mental representations called imagens and logogens. Also, the amount of time spent examining an image may determine the extent of information that is communicated. Animated images enable the presentation of causality and spatial information. Concepts that are not readily conveyed using static images may be expressed more easily with words or animations. Colin Ware states that "animation brings graphics closer to words in expressive capacity."
There is also the danger of presenting misleading or incorrect information through images. Interpretation of images are subject to one's own bias and habits of observation.
Specific subject matter, such as plant parasitic nematology, should include some form of language along with imagery.
Paivio, A. 1987. Mental representations: A dual coding approach. Oxford Press.
Ware, C. 2000. Information visualization: Perception for design. Academic Press.