Multimedia Cognitive Learning Theory (Meyer, 2001), basically – there are three assumptions:

1. 2 separate channel for input – audio + visual
2. Limited to 7 elements
3. Active learning – build connectivity between separate channel

Learn more from https://www.youtube.com/watch?v=sP98_CTjXNo

12 Principles for Multimedia Learning Theory

In the book Multimedia Learning (Cambridge Press, 2001), Richard E. Mayer discusses twelve 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.
3. Redundancy Principle – People learn better from graphics and narration than from graphics, narration and on-screen text.
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 narration 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

https://www.youtube.com/watch?v=0aq2P0DZqEI&t=63s

or here

https://www.youtube.com/watch?v=stJ-MkTgRFs&t=138s