How it all works: Working memory (WM) actively forms knowledge structures called schemas that are then stored in long term memory (LTM). However, WM has very little storage capacity, and is easily overloaded. WM can only process “7 +/- 2” schemas of memory at a given time. The complexity of the schemas a person is able to process in WM varies with that person’s expertise and experience level. The more knowledge and skills stored in LTM, the greater the WM capacity of complex schemas.
Processes of learning: Attention, Activation of prior knowledge, Elaboration and rehearsal, and Encoding and retrieval (Clark, Nguyen, & Sweller, 2005)
Learning can be deeper when participants have multiple sensory opportunities to encode information into LTM schemas. Incorporate text and visuals in the most cognitively efficient manner possible. In addition, efficient use of both visual and auditory modalities extends WM capacity. Evidence is found that dual encoding with either two visual or two auditory components overdrives WM capacity, but one auditory and one visual component maximizes the capacity of each processor in WM.
Applying cognitive load theory to PowerPoint: Using PowerPoint simply as a “convenience for the speaker can be punishing to both content and audience” (Tufte, 2003). Slide presentation software like PowerPoint often stacks so much textual information in such little time frames as to hinder the cognitive processing capabilities of the audience.
Lesson: Be cognizant of your audience, choose media that help extend the WM capacity of your learners with the hope that they are able to retrieve, maintain, and incorporate knowledge into their LTM schemas.
References:
Clark, R.C., Nguyen, F, & Sweller, J. (2005, December) “Efficiency in eLearning: evidence based guidelines to manage cognitive load”. Pfeiffer.
Tufte, E. (2003, September). PowerPoint Is Evil. Power Corrupts. PowerPoint Corrupts Absolutely. Wired.
