As I read about the Coherence Principle two things immediately popped into my head. First, the 1976 cookbook “More with Less” , and second, one of my favorite sayings…”KIS” or Keep it Simple!
The Coherence Principle states “adding extraneous material can hurt learning”. The Coherence Principle has three main points:
- Avoid extraneous audio
- Avoid extraneous graphics
- Avoid extraneous words or text
While at first glance it might seem like a good idea to add sound, graphics, or words to a multimedia presentation to “spice it up” and make it more interesting, studies show that the extra content interferes with the cognitive process of creating a model in working memory. The Coherence Principle makes sense when you look at it from the perspective of the learning goals, instructional designers should “avoid anything that does not support the instructional goal.” (Clark, 2008, p. 151)
A poor example of the Coherence Principle is found in figure 8.1 in the text (p. 152). The designer added additional interesting information about the history of spreadsheet software. However, adding this information breaks the Coherence Principle. The goal of the instruction is to learn how to use a spreadsheet software & the history is NOT part of the goal. This added information while it is interesting & nice to know, is irrelevant to the learning goal & may in fact interfere with the student’s’ working memory. The added information can overload working memory with irrelevant information & hinder a student’s ability to create their own model in working memory.
Another example is seen here in one of my own classroom presentations. This images is from a presentation on Newton’s Laws of Motion. The information on the slide is “nice to know”, but is not necessary to the learning how to apply the three Laws of Motion. I have taken this slide out of the presentation because it is irrelevant text that is not necessary to learning the three Laws of Motion.
A better example of the Coherence Principle from my own classroom is the slide to the right. The slide does not have any extra sound, graphics, or text.The narration is simple: “To resolve a Force vector into its components, follow the rules for vector resolution. The horizontal component is F times cosine theta & the Vertical Component is F times sine theta.
The Coherence Principle is a natural extension of the other Multi Media Principles. The principles that we have learned about are:
- Multimedia: use images (graphics, animations) along with words.
- Contiguity: Align text with corresponding images.
- Modality: Present words as audio rather than text
- Redundancy: Explain graphics with narration (preferably…Modality) or text, but NOT both.
- Coherence: Avoid extraneous audio, graphics, words.
To me, all the principles work together and suggest that the best multimedia presentations limit the information to what will achieve the learning goals. The principles all point to maximizing the dual channels of audio & visual, and recommend ways to limit overload in working memory by using: images with relevant narration (or text) in order to maximize a learner’s’ ability to process the information in working memory. As I create future presentations, and rework old presentations I am going constantly remind myself that less is more!
Clark & Mayer explain that people learn when “a change occurs” that is personal and this change occurs in within the learner’s information processing system. (p 33). The Coherence Principle paves the way for the learning to occur as the Principle supports limiting the amount and type of information that goes into the working memory to process & create meaning.
I personally find this principle very applicable (although I need to practice employing it more often!). It makes perfect sense to me to limit information so students can process the key ideas. This class has really opened my eyes, and I can see in my own classroom how I sometimes (OK, often) embellish presentations with “nice to know”, but not “need to know” information. I have gone back to some of my presentations as a result of this class and reduced the content on each slide, maximized images with clear narrations, and have taken out information that is “fluff”. I know there is still more to learn, but I am looking forward to the chance to apply these principles in my own teaching.
One of the challenges of the Coherence Principle is to “stimulate interest without adding extraneous material that distracts from the cognitive objectives of the lesson.” (Clark, 2008, p, 173). One thing that I enjoy about this text is that the authors explain how research supports the Multi Media Principles, but also explain that additional research is needed to delve into other questions including how do the principles affect more advanced learners? Anecdotally, I can see how the Multi Media Principles that we have learned about are very powerful for novice learners. I can see that in my two different sections of Physics Honors vs College Prep (CP), the Honors students tend to come to class with more background knowledge in Physics & Math. I observe that when I limit the amount information (Coherence Principle), my CP students seem to “pick up” the ideas more easily. The challenge now for me will be to update the multimedia & employ more of the Principles. Again, I do not have hard evidence, just my anecdotal observations but based on this class & my observations, I plan to employ more of these Principles as I rework my curriculum this summer.
Clark, R. C., & Mayer, R. E. (2008). E-learning and the science of instruction, 3rd edition. Pfeiffer: San Francisco, CA.
Image Credit: Doris Janzen Longacre – More-With-Less Cookbook. retrieved from: https://en.wikipedia.org/w/index.php?curid=38805641