This is to debate Multimedia Learning by Mayer. You may want to read the text The Cognitive Theory of Multimedia Learning by Stephen D. Sorden, available on the Moodle (adapted version also). You may also want to read the text Cognitive Theory of Multimedia Learning by Michelle Rudolph, which is mostly directed to multimedia material designers (educational videos in particular)
In the book Multimedia Learning (Cambridge Press, 2001), Richard Mayer discusses 12 principles that shape the design and organization of multimedia presentations:
1. Coherence Principle – People learn better when extraneous words, pictures and sounds are excluded rather than included.
2. Signaling Principle – People learn better when cues that highlight the organization of the essential material are added. (in L2, there is Input Enhancement here and here)
3. Redundancy Principle – People learn better from graphics and narration than from graphics, narration and on-screen text (there is the reverse redundancy effect for L2 learners, eg. here).
4. Spatial Contiguity Principle – People learn better when corresponding words and pictures are presented near rather than far from each other on the page or screen.
5. Temporal Contiguity Principle – People learn better when corresponding words and pictures are presented simultaneously rather than successively.
6. Segmenting Principle – People learn better from a multimedia lesson is presented in user-paced segments rather than as a continuous unit.
7. Pre-training Principle – People learn better from a multimedia lesson when they know the names and characteristics of the main concepts.
8. Modality Principle – People learn better from graphics and narrations than from animation and on-screen text.
9. Multimedia Principle – People learn better from words and pictures than from words alone.
10. Personalization Principle – People learn better from multimedia lessons when words are in conversational style rather than formal style.
11. Voice Principle – People learn better when the narration in multimedia lessons is spoken in a friendly human voice rather than a machine voice.
12. Image Principle – People do not necessarily learn better from a multimedia lesson when the speaker’s image is added to the screen.
The author also talks about the principles involved in:
reducing extraneous processing – coherence, signaling, redundancy, spatial contiguity, temporal contiguity
managing essential processing – segmenting, pre-training, modality
fostering generative processing – multimedia, personalization, voice, image
Also, you may want to look at the diagram, below, proposed by the author, to explain the whole process of comprehension based on both visual and auditory input (via the two different channels).