Cognitive load refers to the amount information the brain has to juggle when it's thinking, reasoning, or solving problems. If you're feeling overwhelmed listening to someone explain a new idea or concept, chances are you're experiencing too much cognitive load (or working memory overload).
Some recent presentations and papers on cognitive load will be helpful for increasing awareness about how information may be effectively presented, but the researchers still underestimate the diversity of their audience. For instance, in this diagram, the argument is made that the text on the left splits attention compared to an integrated diagram on the right. In inaccurate soundbyte fashion, one news article heralds the death of Powerpoint presentations, but this is a bit premature. When we actually assess what students can manage, we've been impressed by the diversity of "preferred learning or working memory style" that exists.
Now, that is not to say, that educational researchers can't survey the most effective ways to reach a majority of students, but averaging the results won't tell you the most effective way to teach a particular student.
The problem is, some students will struggle with visual material and want to read through the text before they get to the figure, while others will want to skip the text and just look at the visual figure, while still others will need both - in an integrated fashion. And that doesn't even factor in the differences that exist with routes of learning- listening and seeing. Some will want to see and listen at the same time, while will prefer to uni-task...just listen or just see, before putting information together. The uni-taskers are often great note co-op people or natural online learners.
Take-home point: For the classroom, what may seem to be redundant information in a presentation, may be necessary for students with different information processing preferences.
There are helpful points that cognitive load theorists make here though...for instance, the need to present examples of correctly solved and fill-in-the-blank problems (1 step-at-a-time), but it's important to realize that troubleshooting an individual student's struggles might require trying a variety of approaches.
Additional tips for teaching overwhelmed students: break problems down into smaller bits, providing examples of correctly solved, goal-free, and completion problems, allowing work to be performed "open-book" (e.g. sheet of formulae, multiplication table, new vocabulary), use accommodations (scribe, keyboard, etc.).
In the brain study below, overlapping and distinct patterns of brain activation were seen for visual attention and cognitive load or working memory- this means that although there's some overlap, there are also distinctions. As it turns out the distinctions (attention vs. working memory) are easier to see by brain scan than ADHD checklist. Buyer beware!
Another point worth noting in the figure, is the involvement of the cerebellum in managing "cognitive load".
The cerebellum is a particularly easy to injure with mild birth stress, prematurity, deprivation, or conditions like the autism spectrum disorders - impaired cerebellar function might therefore a significant contributor to a student's working memory limit or his or her tendency to overload with too much information coming in at once. Other signs of cerebellar dysfunction: floppy tone, motor coodination problems, difficulty with multi-tasking, and sensory-sensory or sensory-motor coordination.
Cognitive Load Theory Presentation pdf
Cognitive Load and Learning press release
Joke Gettysburg Address in Powerpoint
Making of the Gettysburg Address in Powerpoint
Eide Neurolearning Blog: Easing the Work in Working Memory
Learning Efficiency and Cognitive Load / E-learning
fMRI of Working Memory and Attention
Eide Neurolearning Blog: The Cerebellar Child