Learning science supports the idea of minimising student cognitive load to maximise their learning. Part I of this post suggested specific strategies, and Part 2, below, highlights learning science research regarding cognitive load.
Introduction: Evidence & Principles
Cognitive load refers to the amount of mental effort expended in your brain’s working memory. Humans only have so much working memory available. When learning new material, what may be a simple concept for the instructor may be much more complex for the students. Thus, it is easy to overload students with too much information so that they miss some ideas or points that we think are important. In my previous post I suggested 4 strategies to lower the cognitive load for your students to help them learn. In this post I’ll talk about the evidence and the principles behind these strategies.
Understand Working Memory
You can’t teach everything. And even if you could, students couldn’t absorb it all. That’s because working memory is finite. Long term memory has almost unlimited storage space, but working memory can handle only so much information at a time. How much information? Cognitive science research tells us the answer is ~4: four new ideas or concepts, four new elements, four variables that have to be juggled at the same time. And this is in the best of circumstances, when our students are native language speakers, feel like they belong in the course, or are not preoccupied with matters beyond the classroom. Think of working memory as an empty glass. Once you fill it with water, adding more water will result in it spilling out. When you provide your students with too much information, some of it won’t be taken in and it’s as if you never taught it.
Prioritising what you want students to learn is one way to help reduce cognitive load. For instance by identifying the 3 main points for your instruction, you ensure that students learn and remember what YOU think is important. Because we know working memory is limited, it’s important to keep your main points to three and not eight.
Provide Navigation Regularly
Prioritising is important, but it’s not enough. Students also need help with navigation through all of the material you want them to learn. An outline slide at the beginning of a lecture (whether F2F or video) is an easy way to do this. Referring to the outline throughout the presentation is a way to reorient students to your priorities. You can refer to your outline with verbal cues such as “The first strategy is…” and “The second strategy is…” Research has indicated that the simple act of providing these verbal cues results in improved student recall. In lectures without verbal cues, student recalled 21% of information. In lectures of the same content with verbal cues, students recalled 39% of the information.
Embed Consolidation Practices
Another challenge for instructors is recognising what constitutes a single piece of information for students. What might be a single element to an expert (say the scientific method ) could be a meaningless collection of elements to students (ask a question, gather information, make a hypothesis, test the hypothesis, analyse the data, modify the hypothesis). Furthermore, in addition to being exposed to new ideas or concepts, students are often also exposed to new vocabulary. We also want them to connect new information to what they already know.
Experts are able to work with more information than novices because they are able to chunk related elements into a meaningful single element. This was demonstrated in studies of chess players who were asked to memorise as many chess pieces as they could on a mid-game chess board. The study compared the ability of grand master chess players to that of beginning chess players. The experts were able to memorise 15 pieces and the beginners were only able to memorise five. Why? Did the experts just have a better memory than the beginners? No. When presented with a chess board with pieces randomly scattered, the experts then did no better than the beginners. Because of their vast experience, the experts were able to chunk the chess pieces into meaningful elements. Where the experts saw a configuration that made sense to them, the beginners only saw individual chess pieces.
What makes this even more difficult for your students is that you as an expert may not realise that you store information in these meaningful chunks. The cluster of chess pieces means something to the expert, however to the student it’s just a collection of individual pieces that have to be memorised. This is why we can sometimes be surprised when students don’t remember something that we think is simple. It is simple for us, but for your students you may be overloading them with individual pieces.
Providing your students with an organising schema, or advance organiser is a way to support them in creating chunks. These learning aids help them organise and categorise the new information that is provided to them. In this way you are training students to think like an expert, which is a skill that can persist long after your class is over.
Collect Student Feedback
So how do we know if we’re overloading our students? A very simple strategy is to ask them. Collecting early term feedback can alert you to areas that may need attention in your course with enough time to make adjustments. A research study has demonstrated that collecting and acting on early term feedback provides benefits for students and is correlated with higher end-of-semester ratings. In this study, instructors who collected and read early term feedback from their students without discussing it saw a 2% increase in end-of-semester ratings. When they read and discussed the feedback but didn’t make any changes they saw a 5% increase. When they read, discussed, and made changes they saw a 9% increase. Some questions that might help you determine if your students are overloaded include “How is the pace of the course for your learning?” “What is helping your learning in this class” “How many hours a week do you spend on this course?” “What is one suggestion for change that would improve your learning?”
On “Spoken Organizational Lecture Cues and Student Notetaking as Facilitators of Student Learning” describes the impact of verbal organizational cues.
The “Chess Studies and Chunking” processes are described in Chapter 2, “How Experts Differ from Novices” in How People Learn, Bransford, J., National Academy Press, Washington, DC (2000).