John Sweller Interview 9: CLT – misconceptions and future directions

This is part of a series of blogs detailing a discussion that I had with John Sweller in mid 2017. See all parts of this series on this page. 

Update: I have now written a book that summarises Cognitive Load Theory in concise and practical terms. John Sweller played a key role in the writing process and has described it as ‘An indispensable guide to Cognitive Load Theory for Teachers'. Find out more here. 

OL: What do you think is the biggest misconception about cognitive load theory that people have that you would really like to clear up?

JS: It’s only been very recently that people started taking notice of Cognitive Load Theory. For decades I put papers out there and it was like putting them into outer-space, you know, they disappeared into the ether! So, the issue of misconceptions in cognitive load theory didn’t arise. I guess the most common one is that really all I’m talking about is: ‘Don’t give students too much work to do at once'. That’s not really what I mean. It’s true; don’t give them so much work that they can’t get through it all. But that’s not what Cognitive Load Theory is about. What Cognitive Load Theory is about is you can teach the same stuff by reducing working memory load or by increasing working memory load and the issue is, how do you decrease it? And the whole purpose of decreasing it is so you can give them more information that is important. Cognitive Load Theory does not say: ‘Don’t teach them very much'. Cognitive load theory says: ‘Teach them as much as you possibly can because it’s important in any advanced industrial commercial society. But teach them in such a way that they can take it in without overwhelming working memory’.

OL: What are you most excited about in terms of where CLT is going at the moment?

JS: It changes whenever we have a brand new area and in the last few months we have a brand new area. There’s no publications I can point you to yet because there’s nothing out there but we’ve got experimental data. We’ve always assumed that working memory capacity was essentially fixed. The only thing that changes is what’s in long term memory. If you’ve got a lot of information in long term memory, bring it into working memory and you’ve got a huge increase in working memory. But other than that, working memory is fixed. It has become clear recently that we have what we called working memory resource depletion effects and that means, if you’ve been using your working memory, especially in a particular area, heavily for a while, after a while, and you would have experienced this yourself, your working memory keeps getting narrower and narrower and narrower and after a while it just about disappears. You may need to rest. You may even need a rest until the following day. Get sleep in between. That means that at rest, your working memory comes back.And we’re getting some data on that now. (Since this interview was conducted, some research has been published on this. See Greg Ashman's summary of the article here, and the original article here)

OL: That’s interesting. And that relates to something else I’ve heard about. I’m sure you’ve heard about cognitive bandwidth obviously?  But the work of Sendhill Mullainathan, do you know that work? They did this really interesting experiment (see the paper here). They work with the impacts on working memory of being under financial stress. They did this experiment in a mall in New Jersey. They had two experimental conditions. In the first, they said: “Ok John, imagine that you just crashed your car and it’s going to cost $1500 to fix” and the other condition they said: “John, imagine you just crashed your car, it’s going to cost $150 to fix.” And then after they’d done that, they got you to complete some cognitive tasks, such as Raven's Matrices.

JS: Oh, I think I see where this is going.

OL: What they found was that in those who weren’t under financial stress, the $150 vs. $1500 made no difference, but for those who were under financial stress, it made a big difference. So, for those with less money, their brain suddenly decided to process in its subconscious: “Oh, how am I going to do this? Where’s the money going to come from?’ And it had a big effect. So it’s kind of similar. But the other study Mullainathan did,  was they tested the working memory, or performance on Raven's matrices, of farmers in developing countries. And they tested them before harvest, when they were still waiting and unsure of whether their crop was going to come to fruition, and then after, when they had the money. And they saw big impacts of that as well. So there’s all this stuff in the back of our heads that’s actually using up our cognitive bandwidth (working memory) and we’re just not aware of it at all.

John Sweller: And it may not be going on in the back of our heads. It might be going on right in the front of our heads. Two or three years ago I had an academic from Canada, Kris Fraser, who came on sabbatical to visit me and she was a medico, and she was looking at emotion and she got some really interesting results. She tested medical students practicing on plastic models. She had one group of people who had to learn to give treatment for whatever the condition was, but during practice, the patient died.  The other group, learned to give exactly the same treatment, but in this case, the patient lived and recovered. What they then they did was look at how much they had learned, and what they found out was that the people whose model had died had learned less.

OL: Yeah, because they were all stressing out about how they’d killed someone.

JS:  Exactly. So, as I was saying before when we were talking about motivation, you know, these things shouldn’t be mixed up. At that time, I began to think, this is still valid, ‘Well maybe motivation and emotion can be connected in this way?'. I obviously still haven’t decided whether these factors can be related.

OL: It’s occupying a working memory slot or number of slots of the seven plus or minus slots available.

JS: Exactly. If you’re worrying about the idea: ‘My patient died’. You’re not learning. If you’re worried about: ‘How do I afford 1500 dollars’, you’re not going to learn as much.

OL: If you worry about: ‘If I don’t do well on this tests I’m not going to be able to get into the uni course I want to do, etc etc’.

JS: Tell me about it!

OL: Well thanks you for your time today John.

JS: Oh good! It’s good talking to you!

You might also like to check out:

Education Research Reading Room Podcast Episode 9 with Andrew Martin on Load Reduction Instruction, Motivation and Engagement, also available on iTunes.

All posts in this series:

1. Worked Examples – What's the role of students recording their thinking?
2. Can we teach problem solving?
3. What's the difference between the goal-free effect and minimally guided instruction?
4. Biologically primary and biologically secondary knowledge
5. Motivation, what's CLT got to do with it?
6. Productive Failure – Kapur (What does Sweller think about it?)
7. How do we measure cognitive load?
8. Can we teach collaboration?
9. CLT – misconceptions and future directions