The single most important thing for students to know – Cognitive load

Back in 2017 Dylan Williams, Professor of Educational Assessment at UCL described cognitive load theory (CLT) as ‘the single most important thing for teachers to know’. His reasoning was simple, if learning is an alteration in long term memory (OFSTED’s definition) then it is essential for teachers to know the best ways of helping students achieve this. At this stage you might find it helpful to revisit my previous blog, Never forget, improving memory, which explains more about the relationship between long and short-term memory but to help reduce your cognitive load…. I have provided a short summary below.

But here is the point, if CLT is so important for teachers it must also be of benefit to students.

Cognitive load theory
The term cognitive load was coined by John Sweller in a paper published in the journal of Cognitive Science in 1988. Cognitive load is the amount of information that working/short term memory can process at any one time, and that when the load becomes too great, processing information slows down and so does learning. The implication is that because we can’t do anything about the short-term nature of short-term memory, we can only retain 4 + or – 2 chunks of information before it’s lost, learning should be designed or studying methods changed accordingly. The purpose of which is to reduce the ‘load’ so that it can more easily pass into long term memory where the storage capacity is infinite.

CLT can be broken down into three categories:

Intrinsic cognitive load – this relates to the inherent difficulty of the material or complexity of the task. Some content will always have a high level of difficulty, for example, solving a complex equation is more difficult than adding two numbers together. However, the cognitive load arising from a complex task can be reduced by breaking it down into smaller and simpler steps. There is also evidence to show that prior knowledge makes the processing of complex tasks easier. In fact, it is one of the main differences between an expert and a novice, the expert requires less short-term memory capacity because they already have knowledge stored in long term memory that they can draw upon. The new knowledge is simply adding to what they already know. Bottom line – some stuff is just harder.

Extraneous cognitive load – this is the unnecessary mental effort required to process information for the task in hand, in effect the learning has been made overly difficult or confusing. For example, if you needed to learn about a square, it would be far easier to draw a picture and point to it, than use words to describe it. A more common example of extraneous load is when a presenter puts too much information on a PowerPoint slide, most of which adds little to what needs to be learned. Bottom line – don’t make learning harder by including unimportant stuff.

Germane cognitive load – increasing the load is not always bad, for example if you ask someone to think of a house, that will increase the load but when they have created that ‘schema’ or plan in their mind adding new information becomes easier. Following on with the house example, if you have a picture of a house in your mind, asking questions about what you might find in the kitchen is relatively simple. The argument is that learning can be enhanced when content is arranged or presented in a way that helps the learner construct new knowledge. Bottom line – increasing germane load is good because it makes learning new stuff easier.

In summary, both student and teacher should reduce intrinsic and extraneous load but increase germane.

Implications for learning
The three categories of cognitive load shown above provide some insight as to what you should and shouldn’t do if you want to learn more effectively. For example, break complex tasks down into simpler ones, focus on what’s important and avoid unnecessary information and use schemas (models) where possible to help deal with complexity. There are however a few specifics that relate to the categories worthy of mention.

The worked example effect – If you are trying to understand something and continual reading of the text is having little impact, it’s possible your short-term memory has reached capacity. Finding an example of what you need to understand will help free up some of that memory. For example…….…if I wanted to explain that short term memory is limited I might ask you to memorise these 12 letters, SHNCCMTAVYID. But because this will exceed the 4+ or – 2 rule it will be difficult and hopefully as a result prove the point. In this situation the example is a far more effective way of transferring knowledge than pages of text.

The redundancy effect – This is most commonly found where there is simply too much unnecessary or redundant information. It might be irrelevant or not essential to what you’re trying to learn. In addition, it could be the same information but presented in multiple forms, for example an explanation and diagram on the same page. The secret here is to be relatively ruthless in pursuing what you want to know, look for the answer to your question rather than getting distracted by adjacent information. You may also come across this online where a PowerPoint presentation has far too much content and the presenter simply reads out loud what’s on the slides. In these circumstances, it’s a good idea to turn down the sound and simply read the slides for yourself. People can’t focus when they hear and see the same verbal message during a presentation (Hoffman, 2006).

The split attention effect – This occurs when you have to refer to two different sources of information simultaneously when learning. Often in written texts and blogs as I have done in this one, you will find a reference to something further to read or listen to, ignore it and stick to the task in hand, grasp the principle and only afterwards follow up on the link. Another way of reducing the impact of split attention is to produce notes that reduce the conflict that arises when trying to listen to the teacher and make notes at the same time. You might want to use the Cornel note taking method, click here to find out more.

But is it the single most important thing a student should know?
Well maybe, maybe not but its certainly in the top three. The theory on its own will not make you a better learner but it goes a long way in explaining why you can’t understand something despite spending hours studying, it provides guidance as to what you can do to make learning more effective but most importantly it can change your mindset from – “I’m not clever enough” to, “I just need to reduce the amount of information, and then I’ll get it”.

And believing that is priceless, not only for studying towards your next exam but in helping with all your learning in the years to come.

Brain overload

Have you ever felt that you just can’t learn anymore, your head is spinning, your brain must be full? And yet we are told that the brains capacity is potentially limitless, made up of around 86 billion neurons.

To understand why both of these may be true, we have to delve a little more into how the brain learns or to be precise how it manages information. In a previous blog I outlined the key parts of the brain and discussed some of the implications for learning – the learning brain, but as you might imagine this is a complex subject, but I should add a fascinating one.

Cognitive load and schemas

Building on the work of George (magic number 7) Miller and Jean Paget’s development of schemas, in 1988 John Sweller introduced us to cognitive load, the idea that we have a limit to the amount of information we can process.

Cognitive load relates to the amount of information that working memory can hold at one time

Human memory can be divided into working memory and long-term memory. Working memory also called short term memory is limited, only capable of holding 7 plus or minus 2 pieces of information at any one time, hence the magic number 7, but long-term memory has arguably infinite capacity.

The limited nature of working memory can be highlighted by asking you to look at the 12 letters below. Take about 5 seconds. Look away from the screen and write down what you can remember on a blank piece of paper.

MBIAWTDHPIBF

Because there are more than 9 characters this will be difficult. 

Schemas – Information is stored in long-term memory in the form of schemas, these are frameworks or concepts that help organise and interpret new information. For example, when you think of a tree it is defined by a number of characteristics, its green, has a trunk and leaves at the end of branches, this is a schema. But when it comes to autumn, the tree is no longer green and loses its leaves, suggesting that this cannot be a tree. However, if you assimilate the new information with your existing schema and accommodate this in a revised version of how you think about a tree, you have effectively learned something new and stored it in long term memory. By holding information in schemas, when new information arrives your brain can very quickly identify if it fits within an existing one and in so doing enable rapid knowledge acquisition and understanding.

The problem therefore lies with working memory and its limited capacity, but if we could change the way we take in information, such that it doesn’t overload working memory the whole process will become more effective.

Avoiding cognitive overload

This is where it gets really interesting from a learning perspective. What can we do to avoid the brain becoming overloaded?

1. Simple first – this may sound like common sense, start with a simple example e.g. 2+2 = 4 and move towards the more complex e.g. 2,423 + 12,324,345. If you start with a complex calculation the brain will struggle to manipulate the numbers or find any pattern.

2. Direct Instruction not discovery – although there is significant merit in figuring things out for yourself, when learning something new it is better to follow guided instruction (teacher led) supported by several examples, starting simple and becoming more complex (as above). When you have created your own schema, you can begin to work independently.

3. Visual overload – a presentation point, avoid having too much information on a page or slide, reveal each part slowly. The secret is to break down complexity into smaller segments. This is the argument for not having too much content all on one page, which is often the case in textbooks. Read with a piece of paper or ruler effectively underlining the words you are reading, moving the paper down revealing a new line at a time.

4. Pictures and words (contiguity) – having “relevant” pictures alongside text helps avoid what’s called split attention. This is why creating your own notes with images as well as text when producing a mind map works so well.

5. Focus, avoid distraction (coherence) – similar to visual overload, remove all unnecessary images and information, keep focused on the task in hand. There may be some nice to know facts, but stick to the essential ones.

6. Key words (redundancy) – when reading or making notes don’t highlight or write down exactly what you read, simplify the sentence, focusing on the key words which will reduce the amount of input.

7. Use existing schemas – if you already have an understanding of a topic or subject, it will be sat within a schema, think how the new information changes your original understanding.

Remember the 12 characters from earlier, if we chunk them into 4 pieces of information and link to an existing schema, you will find it much easier to remember. Here are the same 12 characters chunked down.

FBI – TWA – PHD – IBM

Each one sits within an existing schema e.g. Federal Bureau of Investigation etc, making it easier for the brain to learn the new information.

Note – the above ideas are based on Richard E. Mayer’s principles of multimedia learning.

In conclusion

Understanding more about how the brain works, in particular how to manage some of its limitations as is the case with short term memory not only makes learning more efficient but also gives you confidence that how your learning is the most effective.