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Tuesday, August 09, 2005

Podcast Theory Gap

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Online learners seem to prefer using audio and web-based information in ways that counter what researchers recommend.

Although instructional designers do not often like to mention this, the fact is, it is the rare learner who will sit at a computer and willingly watch a 20 or 30-minute presentation. However, the same learners are happy to listen to an audio file (podcast or book on tape). Although multimedia presentations are not intended to be used in this way, many individuals download the audio aspect separately and listen to it while doing something else, usually something routine: commuting to work, routine data entry on the computer, preparing food in the kitchen, working in the garden.

Later, they will scan through the printout they made. This will be read without the audio.

Do current ideas about working memory and cognitive processing shed any light? What are the implications for developers of online courses, knowing that learners may not be using the media in the environment it was intended?

Fight Audio with Audio: Podcasts and Audio as a Way to Combat Intrusive Thoughts. “Quiet in the library! Turn off music while you’re studying!” Librarians and mothers everywhere utter those words. According to cognitive psychologists who point to the Split Attention Principle and the Coherence Principle, moms and librarians have been right on target. However, millions of computer programmers, writers, students, and artists beg to differ. When they put on headphones and their favorite music, not only do they block out distracting noise which is externally generated, they also help block out intrusive, distracting thoughts that are internally generated. They listen to music as they are reading, as well as when they are doing work that requires intense concentration.

When Retrieving Data, Use Folksonomies and Taxonomies. Why bother to put anything into short-term memory except the most basic of cues or mnemonic tags? Furl, google, and taxonomies will take care of the rest. Right? Many individuals do not even try to organize knowledge in a hierarchical way. Instead, they focus on a connectivist approach, which relies on linking and computer-aided search functions. The Living Taxonomy Project explores some of these implications (, as do e-storage utility programs such as Looksmart’s FURL ( and (, which utilize “social bookmarks.”

What can we make of these habits? How do they relate to current ideas about working memory and principles used in instructional design, such as the “Split Attention Principle” and the “Coherence Principle”?

According to A. D. Baddeley (1986), working memory involves a multi-phase interaction with cognition, so that humans process information from their immediate environment, store data about their past experience, and develop and organizing framework that will support the acquisition of new knowledge.

The implications for the use of audio in e-learning are multiple. First, the audio information should make connections to what is happening in the immediate environment in a way that reinforces an organizing framework that is being developed. Second, the content should help establish connections between past, present, and potential (or future) information so that when new knowledge is acquired, it is organized in a retrievable way. In short, the audio should be classifiable into categories, and of sufficient flexibility to allow cognitive processes to store, retrieve, and organize information.

According to Baddeley, short-term working memory is limited. The way the brain process information has to do with the fact that it has limited capacity in two channels that gather and process information: the auditory and visual. The “Split Attention Principle” suggests that one should not overload either one of the channels, and that the two channels should reinforce each other.

To put it another way, one should avoid cognitive overload, and audio information should contain clear signals to connect it to the verbal and visual information. Extraneous or distracting auditory information should be avoided, and one should not require the user to require the full text script along with the audio.

This is not to say that it is not useful to have a full-text script available. However, in a presentation, it is better to keep the verbal and visual elements organized in complementary components.

R. E. Mayer and R. Moreno (1999) conducted research that reinforced the idea that cognitive overload is a barrier to learning. According to their findings, an ideal learning environment minimizes or eliminates irrelevant sound / audio. They pointed to the “Split Attention Principle,” which states that “students learn better when the instructional material does not require them to split their attention between multiple sources of mutually referring information” (Moreno and Mayer, 2003). Further, all audio should be carefully designed so that it reinforces the message being presented via other media.

The “Coherence Principle” (Moreno and Mayer, 2003), similarly reinforces the importance of avoiding extraneous and/or irrelevant audio. They also discuss the importance of verbal cues and signs.

It bears pointing out that although the findings by cognitive psychologists incorporate models of the brain and brain function that have been recently developed due to new technologies and techniques, they reinforce notions that have been in circulation since Roman times.

Classical rhetoric and oratory contains the same basic concepts as the principles discussed above, and it proposes structure and technique for doing so. Horace (Ars Poetica) applies the concepts to written discourse that would also be presented in oratory. Later, the elocutionary movement in England, which was deeply influenced by classical Greek and Roman texts brought together notions about how the mind makes meaning (deductive and inductive reasoning), and presentation. George Campbell and Richard Whately were noted in this field. Whately’s Elements of Rhetoric (1828) and George Campbell’s The Philosophy of Rhetoric (1841) both deal with how to organize a speech, presentation, or written argument. Their focus on logic privileges ideas about how the mind makes meaning, and where, why, and when the mind latches onto (recognizes), then organizes and processes information.


Baddeley, A.D. (1986) Working memory. Oxford, England. Oxford University Press.

Campbell, George. (1841). The Philosophy of Rhetoric.

Cicero. Partitiones Oratoriae.

Chandler, P. & Sweller, J. (1992). The split-attention effect as a factor in the design of instruction. British Journal of Educational Psychology, 62, 233-246.

Craig, C. P. (1985). The Structural Pedigree of Cicero's Speeches Pro Archia, Pro Milone and Pro Quinctio, CP 80: 136-37.

Horace. Ars Poetica. (The Art of Poetry).

Mayer, R. E. (1997). Multimedia learning: Are we asking the right questions? Educational Psychologist, 32, 1-19.

Mayer, R. E. & Anderson, R. B. (1991). Animations need narrations: An experimental test of a dual-coding hypothesis. Journal of Educational Psychology, 83, 484-490.

Mayer, R. E. & Anderson, R. B. (1992). The instructive animation: Helping students build connections between words and pictures in multimedia learning. Journal of Educational Psychology, 84, 444-452.

Mayer, R. E. & Moreno, R. (1998). A split-attention effect in multimedia learning: Evidence for dual processing systems in working memory. Journal of Educational Psychology, 90, 312-320.

Mayer, R. E., Moreno, R., Boire M., & Vagge S. (1999). Maximizing constructivist learning from multimedia communications by minimizing cognitive load. Journal of Educational Psychology , 91, 638-643.

Moreno, R. & Mayer, R. E. (2000). A coherence effect in multimedia learning: The case for minimizing irrelevant sounds in the design of multimedia instructional messages. Journal of Educational Psychology, 97, 117-125.

Moreno, R. & Mayer, R. E. (1999). Cognitive principles of multimedia learning: The role of modality and contiguity. Journal of Educational Psychology, 91, 358-368.

Moreno, R. & Mayer, R. E. (2003). A Learner-Centered Approach to Multimedia Explanations: Deriving Instructional Design Principles from Cognitive Theory.

Mousavi, S.Y., Low, R., & Sweller, J. (1995). Reducing cognitive load by mixing auditory and visual presentation modes. Journal of Educational Psychology, 87, 319-334.

Paivio, A. (1986). Mental representation: A dual coding approach. Oxford, England: Oxford University Press.

Sweller, J. (1988). Cognitive load during problem solving: Effects on learning. Cognitive Science, 12, 257-285.

Sweller, J., Chandler, P. (1994). Why some material is difficult to learn. Cognition and Instruction, 12, 185-233.

Whately, R. (1928). Elements of Rhetoric.


This article appeared in a slightly different form on xplanazine ( This is the podcast version.

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