Final Redesign - Development


(note: complete original and revised presentation are at the bottom of the page)

Redesign:
The redesign itself focused on three major areas:
  • reducing cognitive overload
  • balancing verbal and non-verbal channels
  • improving design of presentation

Reducing Cognitive Overload:
The original presentation contained material that was beyond the scope of a module in an introductory course and was overwhelming to novice learners. Several slides, such as the one shown here, were removed completely from the presentation. This slide references concepts (impulse train, sidebands, and the sinc function) from engineering and communications disciplines. Even if the instructor reassures the learners that they are not responsible for this information, merely displaying the slide will push the learners over the edge into cognitive overload. In other places, text was greatly reworded and reworked for clarity.

CogOL_Before.010.jpg
Screen shot of information overload


Balancing verbal and non-verbal channels:
In his Cognitive Theory of Multimedia Learning (CTML), Richard Mayer explicates his dual-channel assumption - that the human information processing system contains both an auditory/verbal channel and a visual/pictorial channel one, and that students learn better from words and pictures than from words alone. In the redesign process, I added several images and diagrams to stimulate both of these channels.

This also served a second purpose. Since the guidelines of good graphic design and powerpoint development warn against overcrowding any single slide, in adding diagrams I also had to expand a concept across several slides. The benefits to spreading a single concept out are many - cognitive load is reduced, the instruction proceeds in smaller stages, and there is an opportunity for questions before moving on.

Before:
DualChanbefore.006.jpg
Before


After:
DualChanAfter.009.jpg
After
DualChanAfter.010.jpgDualChanAfter.011.jpg

Improving Design of Presentation:
The powerpoint design did not contain any major violations. It was simple (adhering to the KISS priniciple - Keep It Simple, Silly) It also used good color contrast, repetition, alignment, and proximity (the CRAP principle). It was boring, however. The addition of the diagrams explained above did much to help this, but there were places were more interest and excitement could be used effectively. As the student try to wrap their heads around the incredible accuracy of the digital quantization they are learning about, they are asked to:
"imagine a stack of paper a mile high. The thickness of a sheet of paper is the accuracy of a 24-bit quantization interval"

A simple graphic on the following slide serves to emphasize the point.

PaperStackafter.029.jpg


Additional materials for the instruction are discussed in the Implementation section.



Original Presentation / Instructional Materials:

Download as a Microsoft Powerpoint or an Apple Keynote file.

Re-Designed Presentation / Instructional Materials:

Download as a Microsoft Powerpoint or an Apple Keynote file.