Sweller’s Cognitive Load Theory in Action

Author:  Oliver Lovell

Publisher: ‎John Catt Educational

Publication Year: 17 November 2020

At the beginning of Lovell’s ‘Sweller’s Cognitive Load Theory in Action’ (2020) is this remarkable quote from Dylan Wiliam: “Sweller’s Cognitive Load Theory is the single most important thing for teachers to know.”

Lovell justifies this bold claim by describing the excellent results he has had by putting cognitive load theory (CLT) into practice: “Where once I would see just blank faces and puzzled looks from my students, I began to see cause and effect between my actions and their learning.”

So, what is CLT, and why is it so important? The theory can be summed up in a single sentence: “In order to increase learning, reduce extraneous load and optimise intrinsic load.” Intrinsic load is defined as “the load associated with the core learning taking place; it is the load that we want students’ working memories to be occupied with.” Extraneous load, on the other hand, is “the manner and structure of instruction, and draws students’ working memory resources away from the core information to be learned.”

The theory is grounded in the idea that while the capacity of our long-term memory is effectively limitless, our working memory is not. Too much extraneous load will reduce the possible intrinsic load; effective instructional design should consider these limitations. CLT provides insights into how to structure information to optimise learning by managing the cognitive load imposed on learners.

Lovell’s book is divided into three parts. The first deals with the academic theory behind CLT; this part may, as Lovell says, be passed over by those teachers who are uninterested in theory. The second part is titled ‘Optimise Intrinsic Load’; it covers useful techniques for doing this. The third, and longest, section is called ‘Reduce Extraneous Load’.

In the second part of the book, Lovell offers three main techniques, with many subdivisions and variations, for optimising intrinsic load. These include ‘Pre-teaching’, and he offers a variety of methods for doing this. Another technique is ‘Segmentation’, or ‘Chunking’: “Intrinsic cognitive load can be reduced by breaking up a task into bite-sized chunks”. The third technique is ‘Sequencing and combination’: “Part-whole means building constituent skills and knowledge before putting it all together. Whole-part requires providing a general overview first, followed by more focused practice of individual segments.”

All of these will be familiar enough to experienced teachers, although even they may usefully study some of the many examples given. They do of course come with a caveat: the Expertise-Reversal Effect. Simply stated, this “suggests that learners need differing amounts of support depending upon their level of expertise.”

It is the third section of the book, ‘Reducing Extraneous Load”, that is perhaps the most rewarding. Indeed, Lovell himself says that “Cognitive load theory has been concerned primarily, though not exclusively, with reducing extraneous cognitive load.”

The first way of reducing extraneous load is to eliminate redundant information; redundancy happens most often when the same information is presented in different ways. For example, when a speaker has a presentation on slides and proceeds to read from them. According to CLT, this is undesirable because all language, whether written or spoken, is processed in the same area of working memory. Therefore, the two streams of information are interfering with each other, and extraneous load is being introduced.

Images and words are often another source of extraneous load. The book gives several examples of clear diagrams being accompanied by redundant written explanations and shows that these explanations hinder learning. Images and text should not communicate the same thing.