Cognitive Load Theory (CLT). Its appearance frequency on my Twitter timeline is ever-increasing, and whilst I could get a general grip on it from what people were saying – as it seemed rather like common sense – I did some reading today of various things, including an interview with its 1988 ‘creator’ John Sweller. I certainly see from my Twitter colleagues that CLT is influencing how many of them are teaching, how they are planning and how they are designing curriculum materials, presentations and so on. It’s fascinating, and quite exciting. I think it is important that this is happening – there is a reasonable evidence base for a lot of the ideas (though plenty of criticisms too).
I am talking as if I am now an expert: I am an amateur, exploring. All I have done is read a few articles, webpages and interviews, and I’ve certainly not read enough about the failings of CLT. I do find that many aspects of the more obvious CLT ideas correspond to what we already do in the classroom, and consequently is largely common sense with a cognitive science phrase/keyword attached to it*.
Most teachers: “If a student is learning a new idea, they’ll learn a lot from someone clearly explaining it and talking through it and using worked examples. Learning is improved most when using worked examples with novices rather than employing problem solving or discovery learning activities so early in their learning. If a student is learning something new that is complex, it needs to be explained incredibly clearly and carefully, often in stages to avoid students getting lost. If a student is proficient at something, or more expert, then being told too many of those simpler things again will not lead to a great deal of learning. Experts will learn more by practising problem solving. Importantly, students who are engaged in the activity and genuinely processing the content will learn the most.”
CLT-lovers: “If a student is learning a new idea, they’ll learn a lot from someone clearly explaining it because this keeps the extraneous cognitive load low to allow more room in your working memory to develop an understanding of the content and/or acquire the skills to take the content further. Being talked through it and using worked examples will demonstrate this clearly; the improved learning in this is known as the worked example effect. Learning is improved most when using worked examples with novices rather than employing problem solving or discovery learning activities so early in their learning. If a student is learning something new that is complex it will place strain on a student’s working memory, possibly because of a high level of element interactivity, causing a high intrinsic cognitive load (the task itself is challenging and requires a student to consider a number of concepts/factors/ideas). It needs to be explained incredibly clearly and carefully, often in stages as this reduces the extraneous cognitive load, which would contribute to the strain on a student’s working memory. If a task is complex and the instruction is not appropriate it will be very difficult for learning to take place. If a student is proficient at something, or more expert, then being told too many of those simpler things again will not lead to a great deal of learning. Indeed, the Expert Reversal Effect shows that too much of this reverses the learning of an expert: redundant information increases the cognitive load. Experts will learn more by practising problem solving. Importantly, students who are engaged in the activity and genuinely processing the content will be devoting some of their working memory to the germane cognitive load which relates to the degree of effort involved in the processing, construction and automation of schemas (a permanent store of knowledge in the long-term memory).”
There are a number of effects as a consequence of CLT, some of which were mentioned above. I wanted to briefly cover some of them here (stolen entirely from here and then slightly adapted):
- Goal free effect: novice learners with a specific learning goal (like a precise question to answer) focus on the goal and pay no/little attention to other information: students have to engage in the process.
- Worked examples effect: using well-planned examples will reduce cognitive load and relieve space in working memory to improve learning.
- Modality effect: two messages on similar elements should be provided through different sensory modalities. For example, an image and text or an image and oral. Research suggests that more memory capacity is available when dual modalities were used. Be careful: it may lead to a split-attention effect.
- Split-attention effect: occurs when learners have to process and integrate multiple and separated sources of information. If a body of text refers to a diagram, it is better understood if the text is integrated into the diagram: students don’t need to split their attention. If your text simply describes the diagram, don’t include it as this adds unnecessary extraneous cognitive load (see Redundancy effect).
- Redundancy effect: when the same information is presented more than once the multiple processing is negative for comprehension since it increases extraneous cognitive load. If novices can benefit from partially redundant information (integrated text and picture for example), expert’s performances can be impaired.
- Element interactivity effect: some tasks have significant element interactivity because there are a number of concepts working together. This needs to be considered in how instruction is planned as you need to avoid as much extraneous element interactivity as possible to ensure there are no negative impacts. High interactivity can contribute to split-attention and redundancy effects.
- Isolated interacting elements effect: with complex models containing multiple interacting elements it is advisable to begin with presenting every element separately. For example, teach students about the structure of the atom and energy transfer before teaching radioactive decay.
- Imagination effect: when experts imagine a procedure or concept they perform better as information is more likely to be transferred from working to long-term memory under imagination conditions rather than studying conditions.
- Expertise reversal effect: with experts, several effects are inversed.
- Guidance fading effect: as expertise is obtained, learners should be less guided in their exercises.
My CLT Considerations
There is so much out there that I need to read about, including the effects mentioned above, and all of the criticisms of CLT. I certainly won’t be accepting the entirety of the theory at face value, but I am going to have a play around with my teaching in the meantime. I will be looking to:
- Plan carefully: minimise unnecessary information and maximise quality and concision of instruction
- Consider more explicitly when certain activities should take place, and use worked examples more regularly when students are novices
- Always present considering the modality effect/dual coding to avoid the split-attention effect
* One can go into much more depth than I am, and will certainly want to if you intend to use CLT to help influence how you teach, plan and design resources/curricula. I openly admit to knowing nothing about the more complex elements of memory, I am just focusing on those elements that I have accessed and are those that are easily accessible for us teachers