The Coherence Principle
The basic idea of the coherence principle is to avoid any extraneous audio, graphics, or words.
Research has shown in all three cases, learning is hampered when extra material is added that is
not relevant to the course (Clark & Mayer, 2008). The coherence principle champions the idea
that only material directly related to the main learning objectives be included. Anything extra, be
it additional facts, “fyi” type quotes, sound effects, or background music, simply take up valuable
space in the highly limited working memory, according to the cognitive theory of multimedia
learning.
Personally, I have seen this principle at work many times. One particular set of presentations was
when I worked at a Fortune 500 company. The first day was nothing but sitting in front of a
computer watching training presentations. To be frank, they were incredibly boring. It was simply
narration, a picture, and the highlights of the narration. There was no background music, sound
effects, or non-pertinent information. At the end of the presentations, there were tests that had
to be passed before moving on. On every test (at least 10), I passed the first time I took it. I had
no prior information about the company or the material being studied. Frankly, I was surprised I
did pass all of them because of how simple (aka boring) they were. At the time, I just thought
the company had been cheap and not spent much time on the training material. I am coming to
learn they did just the opposite.
Another example includes the use of PowerPoint. In this case, the criteria of the coherence
principle were violated. Every year, each of the high schools in my district have a freshman
orientation to introduce incoming freshmen to the school as well as the requirements set forth by
the state. The district had one of the schools design the program. There is quite a bit of
information, so the working memory of these new students and parents would be getting a
workout just based on the sheer amount of information.
The presentation was done on PowerPoint but turned into a video; therefore, the parents and
students watching the presentation had no control over the speed. The video was narrated
verbatim from the words on the screen. Additionally, there was background audio, which itself
sometimes masked the voice of the narrator. According to Clark and Mayer,
“background music and sounds may overload working memory, so they are most
dangerous in situations in which the learner may experience heavy cognitive load, for
example. When the material is unfamiliar, when the material is presented at a rapid rate,
or when the rate of presentation is not under learner control.”
Clearly, this violates the extraneous audio portion of the coherence principle.
The presentation was also presented with extraneous graphics. Many of the slides included
pictures of items that, while academic, did not relate to what was being talked about. For
example, when reviewing the credits needed to graduate, in addition to a mortar board (which
might be considered okay), there were pictures of students with arms around each other,
students carrying books, and students cheering at a sporting event. These extra pictures
interfere with the learners ability to makes sense of the presented material (Clark & Mayer,
2008).
The coherence principle seems to be consistent with the other and works well with the other
principles we have studied thus far. The modality principle, which states that words should be
presented as audio narration rather than text on the screen, is in line with the coherence
principle. The modality principle seeks to reduce the cognitive load on the visual channel and
distribute the information more evenly so new learning can occur. Its elimination of the on screen
text reduces the cognitive load on the visual channel.
Similarly, the redundancy principle, seeks to reduce the cognitive load on any one channel. In
this principle, the designer of the material should explain visuals using narration or text. Once
again, this is consistent with the coherence principle. Removing the text eases the load on the
visual channel. Conversely, removing the audio eases the load on the auditory channel.
The multimedia principle teaches us that words and graphics are more effective than words alone
(Clark & Mayer, 2008). The important part we need to remember when comparing this principle
to the coherence principle is the idea of extraneous graphics. All graphics need to directly relate
to the new material to be learned. Any graphic not directly related needs to be eliminated for the
most new learning to occur.
According to Mayer (1999), learning occurs with the learner engages in three cognitive
processes. First, selecting the important words from a section. Second, being able to organize
those words into a verbal model. And finally, organizing the images. This fits very well into the
coherence principle. If a passage is being narrated and shown on screen, the learner may have
trouble picking out the key words. Additionally, he may turn his or her attention to a visual that
has nothing to do with the presented material, or reading text associated with that visual. Using
the coherence principle to eliminate the material not needed will help the learner achieve the
cognitive processes listed.
This theory was interesting to me. I understand the idea and it is always hard to argue with hard
evidence. I have always been a student that listens to music while doing my work. The research
shows that, while my work is not degraded, it is done slower. From a designer standpoint, I like
this theory. More time can be dedicated to the core material and less time coming up with sound
effects, background music, extraneous graphics, etc. I just have a few questions that I did not
feel were answered. Moreno & Meyer indicated that eight studies had been done regarding the
coherence principle, but did not disclose what subjects and grade levels. Would these results
replicate themselves in other subjects? Would these results replicate themselves for students who
do well in a particular subject? Does age and/or grade level matter? In the example studies,
would the results have been different if we knew which students enjoyed the subjects? I would
like to see more detailed research. I know many of the textbooks we use in traditional classes
have a lot of extraneous information (text and graphics). As a teacher, I use this information to
get students interest. Does the online environment drastically change the idea of extraneous
information? I am definitely in no position to argue the results in an online environment, but my
brief time teaching has shown me that sometimes, the extraneous information is what grabs a
student’s attention.
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(7), 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 March 1, 2009 from
http://imej.wfu.edu/articles/2000/2/05/index.asp