According to the coherence principle, instructional designers should eliminate materials that do not support learning or the instructional goals. These materials include unnecessary audio, graphics, and text (Clark & Mayer, 2008). Many designers think that such additions to e-learning course makes it more interesting, but the opposite is true. When the lesson includes materials that are not relevant to the instructional goal, they can overload learners’ working memory and actually harm learning (Clark & Mayer, 2008).
I have seen the coherence principle abused many times. In college, we were required to complete an e-learning course about finance management. Almost all the students were really frustrated at the end of the lesson since it did not teach us anything. The authors thought that if they make the background fancy, that the course would appeal to college students, but they did not think how frustrated students become when they cannot find little button in the whole graphics. The graphics were too detailed and the instructions were not clear on what the students should look for. It was not the only time when I came across violating of the coherence principle. I agree with the Clark and Mayer, that many e-learning developers want the course to look more interesting or fancy and that is why they overload it with unnecessary details.
I often see the coherence principle abused in PowerPoint presentations. Many presentation authors think that they are required to fill out the whole slide with either text or “cool” pictures that are not related to the lesson. Many professors use PowerPoint presentation as notes for the students so they do not have to take notes by themselves, but this way they completely change the use of the program.
The coherence principle is related to other multimedia principles. For example, the modality principle encourages not to overuse audio, sound, and words (Clark & Mayer, 2008; Moreno & Mayer, 2000).
The coherence principle is based on the cognitive theory which states that the working memory has a limited capacity and can get overloaded if too much information is introduced together.There are two channels for processing visual and auditory material and people can only process a few pieces of information in each of the channels at one time (Clark & Mayer, 2008). If one of the channels gets overloaded by adding too much unnecessary information, the working memory overloads and the learner is not able to process the information and move it to the long term memory.
I agree that the coherence principle is important when creating not only e-learning, but any learning materials. It gets abused too often. Today people think that the e-learning has to look fancy to be effective. Often, authors of learning materials use the newest tools, create catchy videos and presentations, but abuse the coherence principle from the first word through the whole lesson. I think that everyone who has anything to do with learning should get informed about this principle and share it with other educators. Hopefully one day we will be able to prioritize important before fancy.
Clark, R. C., & Mayer, R. E. (2008). E-learning and the science of instruction, 2nd edition. Pfeiffer: San Francisco, CA.
Mayer, R.E. (1999). Multimedia aids to problem-solving transfer. International Journal of Educational Research. 31. 611-623.
Moreno, R., & Mayer, R. E. (2000). A learner-centered approach to multimedia explanations: Deriving instructional design principles from cognitive theory. Interactive Multimedia Electronic Journal of Computer-Enhanced Learning, 2(2), 2004-07. Retrieved July 12, 2012 from http://imej.wfu.edu/articles/2000/2/05/index.asp