E-learning theory describes the cognitive science principles of effective multimedia learning using electronic educational technology. Cognitive research and theory suggest that selection of appropriate concurrent multimedia modalities may enhance learning, as may application of several other principles.
Beginning with cognitive load theory as their motivating scientific premise, researchers such as Richard E. Mayer, John Sweller, and Roxana Moreno established within the scientific literature a set of multimedia instructional design principles that promote effective learning. Many of these principles have been “field tested” in everyday learning settings and found to be effective there as well. The majority of this body of research has been performed using university students given relatively short lessons on technical concepts with which they held low prior knowledge. However, David Roberts has tested the method with students in nine social science disciplines including sociology, politics and business studies. His longitudinal research programme over 3 years established a clear improvement in levels of student engagement and in the development of active learning principles among students exposed to a combination of images and text, over students exposed only to text. A number of other studies have shown these principles to be effective with learners of other ages and with non-technical learning content. Research using learners who have greater prior knowledge in the lesson material sometimes finds results that contradict these design principles. This has led some researchers to put forward the “expertise effect” as an instructional design principle unto itself.
The underlying theoretical premise, cognitive load theory, describes the amount of mental effort that is related to performing a task as falling into one of three categories: germane, intrinsic, and extraneous. Germane cognitive load is the mental effort required to process the task’s information, make sense of it, and access and/or store it in long-term memory (for example, seeing a math problem, identifying the values and operations involved, and understanding that your task is to solve the math problem). Intrinsic cognitive load is the mental effort required to perform the task itself (for example, actually solving the math problem). Extraneous cognitive load is the mental effort imposed by the way that the task is delivered, which may or may not be efficient (for example, finding the math problem you are supposed to solve on a page that also contains advertisements for books about math).
The multimedia instructional design principles identified by Mayer, Sweller, Moreno, and their colleagues are largely focused on minimizing extraneous cognitive load, and managing intrinsic and germane loads at levels that are appropriate for the learner. Examples of these principles in practice include
Reducing extraneous load by eliminating visual and auditory effects and elements that are not central to the lesson, such as seductive details (the coherence principle)
Reducing germane load by delivering verbal information through audio presentation (narration) while delivering relevant visual information through static images or animations (the modality principle)
Controlling intrinsic load by breaking the lesson into smaller segments and giving learners control over the pace at which they move forward through the lesson material (the segmenting principle).
Cognitive load theory (and by extension many of the multimedia instructional design principles) is based in part on a model of working memory by Alan Baddeley and Graham Hitch who proposed that working memory has two largely independent, limited capacity sub-components that tend to work in parallel – one visual and one verbal/acoustic. This gave rise to dual-coding theory, first proposed by Allan Paivio and later applied to multimedia learning by Richard Mayer. According to Mayer, separate channels of working memory process auditory and visual information during any lesson. Consequently, a learner can use more cognitive processing capacities to study materials that combine auditory verbal information with visual graphical information than to process materials that combine printed (visual) text with visual graphical information. In other words, the multi-modal materials reduce the cognitive load imposed on working memory.
In a series of studies Mayer and his colleagues tested Paivio’s dual-coding theory, with multimedia lesson materials. They repeatedly found that students given multimedia with animation and narration consistently did better on transfer questions than those who learn from animation and text-based materials. That is, they were significantly better when it came to applying what they had learned after receiving multimedia rather than mono-media (visual only) instruction. These results were then later confirmed by other groups of researchers.
The initial studies of multimedia learning were limited to logical scientific processes that centered on cause-and-effect systems like automobile braking systems, how a bicycle pump works, or cloud formation. However, subsequent investigations found that the modality effect extended to other areas of learning.