What is Dual Coding?

and how can it be used to promote effective learning in the classroom?

25 August, 2022

Dual Coding is a proven process for learning new content effectively. Let’s find out more:

We’ve all heard of learning styles and probably rolled our eyes at the very mention of it in a Professional Development session. We’ve all done the quiz to find out what kind of learner we are but most likely come to the conclusion that we’re a bit of everything.

That’s where Dual Coding comes in.

Rather than identifying and labelling people as particular types of learners who should favour a particular learning medium, Dual Coding is a scientifically-backed approach that shows that learning is accelerated when both text and visuals are utilised effectively.

How does Dual Coding work?

What we need to know for a start is that verbal and visual information are processed in different ways. While verbal information (e.g. a teacher explaining a concept) is processed bit by bit in a linear way as you hear each word or ‘chunk’ of information, non-verbal information (e.g. a diagram) is processed asynchronously, with the brain instead viewing the information as a whole.

We can gather information more quickly in a visual form than in verbal form which relies on us processing the information as it is delivered. For example, if you looked at the picture below for 1-2 seconds then closed your eyes, you would be able to simultaneously visualise the pasta in the container on the left, the pot in the background and spaghetti getting served up on a plate.

Cooking spaghettiWhereas, if you had the following phrase read to you: “a chef serving up spaghetti bolognaise at a 4-star restaurant in New York”, most likely you would repeat back the sentence in the order you heard it. Being sequential, we can only process the information as we receive it. This is less efficient than processing visual information, however, it provides information that may not have been apparent from just viewing the image.

Students are more likely to understand and remember what has been presented when two process channels are utilised, resulting in a ‘dual coding’ effect. The information is processed and committed to memory in two ways which aids long term retention.

What students (well, all of us actually), find challenging is when we are trying to process information from multiple sources at the same time and feel like we can’t fully concentrate on either.

Teachers can lessen the cognitive load on students’ working memory by presenting information one way e.g. (visually by drawing a diagram) then another way (e.g. verbally through an explanation), making explicit links between the two sources. This will enable Dual Coding to occur.

What does Dual Coding look like in the classroom?

It’s less complicated than it sounds. Here’s a simple example of what you might do in your lesson:

  1. Start with a blank whiteboard.

  2. Draw one section of a diagram.

  3. Give a verbal explanation.

  4. Add labels to the diagram silently.

  5. Give students time to read the labels.

  6. Bring students’ attention back to you and draw the next part of the diagram.

  7. Explicitly gesture to the sections you want students to focus on “Look at this” “Focus on this part of the diagram”.

  8. Repeat so each section is reinforced verbally.

  9. Illustrate how ideas relate to each other or lead from one process to the next.

The benefit of starting with a blank slate is that there is no other work on the board that could distract your students; their attention is solely focused on what you’re about to show them. By drawing then explaining, you are only requiring them to focus on one thing at a time. Avoiding talk while adding labels and in the time afterwards gives them time to process what they see in terms of both the visual diagram and the written word. If we talk at the same time, we’re throwing information at them in too many ways at once and students will end up having to make the decision on where to focus their attention.

By chunking the information and the way we are presenting it, we are able to control the pace and exposure of the new content. We can draw students’ attention to particular sections of a diagram and explain how it connects to the other sections. Building on prior knowledge at each stage is essential for keeping all of our learners on board with the learning.

Drawing a diagram dual coding

What are the benefits of Dual Coding?

  • Can help to ‘break down’ difficult concepts into manageable chunks that students can understand more easily.

  • Directs students’ attention to one thing at a time so they know what to focus on. This is a way of controlling cognitive load as stimuli aren’t competing with each other for the attention of students, but are used in succession to reinforce each other.

  • Helps to build stronger schema (a cognitive framework formed by our prior knowledge and experience that we use to construct meaning when new information is presented to us) because information is presented more than one way and prior knowledge is built upon in a structured, deliberate approach.

  • Improves student motivation, particularly for our lower-ability learners because learning is segmented and manageable.

  • It doesn’t require additional planning or preparation time for teachers...hooray!

Key things to note

An important point to understand is that it’s not just about what you say and show; it’s what you select to say or show at a particular time so students are ready and able to process the information.

Basically what we are trying to do is reduce the cognitive load on our students by presenting information in a way that is clear, not competing for their attention and scaffold them into building their understanding.

It doesn’t matter whether you draw, use videos or static images and diagrams, mindmaps, tables or graphs and whether you use visuals or oral/written language first. The important thing is that the information is presented a couple of ways with the deliberate act of making connections between them.

One mistake we often make (yes, I’m 100% guilty too) is including a random image on a slide because we want to make the content more interesting. Unless it is directly tied to the material and explicitly linked to, then more likely it is serving as a visual distraction to your students.* Keep it simple.

*In saying this, of course we should continue to support our English Second Language Learners with appropriate visual aids where appropriate - I’ll leave that in your capable hands to judge!

Keep it simple

Don’t get students to read along as you read off slides. Instead, get them to just listen or just read the slide then follow up with a verbal rephrasing or explanation, or peer-share discussion. Make sure you limit the amount of content on each slide so that students only have one graph or one diagram or one picture per page.

Ways to use Dual Coding in your next lesson

The most useful part of any new learning is how to apply it in practice, right? Here are some activities that lend themselves to using Dual Coding, many of which you probably already use in your teaching practice. Now you can use them with the knowledge that we want to deliberately connect the visuals and verbal explanations and consciously allow time for our students to process one stimulus at a time!

  • Annotated diagrams, ensuring that these are drawn and explained in parts (I’m sure you’ve got the idea by now!). Any labels should be added within the diagram rather than attached to lines or boxes or within separate keys so that the connections between parts are as clear as possible for your students to follow.

  • Draw & write, give students an image and get them to explain in their own words what the image shows. Same goes in reverse; draw a picture/diagram to go with a verbal or written description.

  • Storyboards, used to show linear learning in a visual form, accompanied by text.

  • Flow diagrams

  • Mind maps, kept simple with minimal text.

  • Pictionary, draw a picture associated with a key word for other students to guess.

  • Venn diagrams

  • Double bubble thinking maps

  • Timelines, created sequentially combining text and images

  • Infographics, with the aim of conveying key information quickly and clearly

  • Flash cards

  • Foldable/interactive notebooks

  • Tree maps

  • Video, discuss then watch a video, watch a video then discuss, watch a video then draw a diagram, read a text then watch a video etc etc

Summing up

Any activity where you are combining words and meaningful visuals is going to help students understand their learning that much better. And hey, you might find it helpful too next time you come to study something new! We don’t need to think of Dual Coding as some tricky new thing that we need to introduce, but just make some slight adjustments to our current practice to help our students really reap the benefits of the learning time in our lessons.

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