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.
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.
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.