Technique 5: Use Dual Coding

When you’re learning something new, text is important. Images and diagrams are also important. But something magical happens if you can combine both text and imagery in your learning materials or notes. The dual coding technique entails combining multiple modalities (i.e. text and images) to gain a deeper understanding about the concept than would be possible with just one or the other.

n Ontario’s Allan Paivio in: 1971

Essentially, there are two main memory systems in the brain, and using both simultaneously improves learning.

“Coding” is how we access, store and process concepts, but it’s also how we retrieve them later. If we code a concept twice—as a verbal and visual piece of data, for example—we give ourselves a greater chance of retrieving that memory later on than if the data had only been coded one way.

The theory has plenty of scientific evidence to support its claims. Brain imaging techniques (MRI and PET scans) can show where brain activity occurs during particular tasks and stimuli, and reveal the distinct neural pathways associated with visual and verbal processes. Dual coding is a technique that takes advantage of the way our brains naturally work.

With dual coding, the whole is greater than the sum of the parts. For example, you might be trying to learn about a complicated physics or biology concept, of which there are several text descriptions and a diagram showing the process. The text and the image do connect to one another, but you have to do the extra cognitive work to figure out how.

If the text and image are combined, however, the relationship between them is clearer and more obvious—so you can more quickly and readily access the fundamental concept. The key is to create your own combined study materials, and to keep it simple at first so as to reduce overwhelm.

By representing one single concept or idea both visually and verbally, and making clear the connection between them, it’s as though you give your brain more “handles” by which to grasp the concept. Dual coding improves your comprehension and your memory. However, there are a few tips to keep in mind:

● Make sure that the images added are actually meaningful and relate to the text. There is no gain to be had in merely adding a picture, and you may unnecessarily add to the mental load.

● Make sure you take the time to mentally integrate both verbal and image data, by exploring the way they mutually explain and support one another. You are not merely creating a picture with some text, but a combined stimulus that tells you more than either modality can in isolation.

● Try combining this technique with your general note-taking system to save space and be more concise.

● Start simple and then add to your study materials as you go. An anatomy diagram, for instance, will be easier to integrate and understand if you begin with the most fundamental labels only.

● Think of how you can condense verbal information using visual clues. Your diagrams don’t have to be realistic—they only have to capture and demonstrate key relationships, functions, processes or ideas. A chemistry diagram, for example, can be a mix of chemical equations with little diagrams of the shape of the molecules.

● You can start with either text or imagery. If you are comfortable with a text description, try elaborating on it with imagery, and vice versa.

● If you have trouble understanding a topic, switch modality—reading a confusing description may make more sense if you try to visualize some imagery to accompany it, and a complicated diagram may be clarified with the careful addition of some explanatory text.

Investigations done both by Paivio and other researchers have shown that recall of verbal information is better if paired with related imagery—whether real or imagined. Other studies have shown that it’s easier to remember concrete topics than abstract ones, with the implication that making abstract concepts more concrete will lead to better understanding and recall.

Finally, in: 1969

“Isn’t this the same as learning styles?”

Despite its enormous popularity in the education sector, the idea that different students have different learning styles (i.e. visual, verbal, auditory or kinesthetic) has not been scientifically proven at all. Thinking that some material is simply not for you may actually limit your learning potential as a student, and lead you to believe that you are simply not cut out for certain subjects—which is not true.

This “neuromyth” goes to show just how unhelpful it can be to rely on theories that only seem to make sense. It seems logical to imagine that people differ in learning style just as they do in personality, but the most effective approach can sometimes run counter to our intuition.

Dual coding is not quite the same as the learning styles theory, and does have considerable scientific backing to suggest its efficacy. Rather than the brain preferring just one modality, it appears to learn best when presented with rich information encompassing several different modalities. This is not surprising when you think that the brain evolved to serve us in a complex, interconnected world that speaks to all our senses at once—life itself doesn’t arrange itself in neat, simplified categories!

Though it’s true that different people will certainly have different preferences and personalities when it comes to learning, it may be more useful to think of the topic itself, and the style of learning it would most benefit from. It’s hard to imagine learning salsa or heart surgery from a book, and just as hard to think of how you’d teach complex calculus without a book.

Some of the perceived benefits of the learning styles theory may actually be hidden benefits of dual coding—not merely presenting information in different forms, but presenting it in more than one form simultaneously.

“My topic really cannot be represented visually, though…”

It’s easy to imagine many scientific or mechanical topics being suited to visual representation, not to mention intrinsically visual areas like art or design. But what if you’re learning about something like literature, history or a new language? Can dual coding still work?

The answer is yes—“visual representation” needn’t be just a picture. You can use more abstract visual elements like tables, flowcharts, timelines, outlines or other graphic organizers to represent information. Again, however, this needs to be meaningfully done: the structure and layout needs to say something useful about the text.

For example, you could use a spider diagram or table to chart out the main components of an essay, and show how each idea relates to the others. Or you could use arrows, shapes and even colors and symbols to illustrate certain ideas and link them together. A timeline or cause-and-effect diagram can lay out chronological events.

It can be a little trickier with some subjects than others, but what’s important is the effort that goes into the production of such combined visual/verbal study aids. In creating these diagrams yourself, you give your brain the chance to see information from a completely different perspective, consolidating your learning. It doesn’t matter too much which modalities you use, or how, only that you are combining them in meaningful ways that actually enhance your understanding.

“Can dual coding only be done using words and images?”

According to Paivio’s original theory, yes. But perhaps we should take a closer look at what he meant when speaking about “words and pictures.” Firstly, “analogue” codes refers to any codes that strongly resemble the thing they’re representing. For example, a near exact copy of a circuit diagram or a photorealistic picture of the anatomy of the skin—i.e., what we might think of as pictures.

“Symbolic codes” are representations of words, and don’t map exactly onto the phenomena they’re describing. These symbols are arbitrary—for example, the squares on a calendar don’t really have anything with the days or months they are meant to represent. So, although words are a part of the model, they can also include symbols, numbers, variables, letters or combinations of letters, etc.

Words and images (and diagrams, symbols, etc.) are the only two modalities supported with scientific evidence.

There is some controversy about this, but it’s likely that the theory would not apply to, say, auditory or kinesthetic codes. While it may prove useful to try, the key is still to form solid and meaningful associations between the two modes, and this may prove impossible for modes other than words and images.

Having said that, there are actually four modes of encoding, which is to be distinguished from dual coding.

When we talk about encoding, we are talking about the process of creating a new memory, and this is a term that is specific to the creation of memories. There are four types of encoding: visual, semantic, elaborative, and acoustic. The first two we’ve already discussed with regard to dual coding, which means that elaborative and acoustic encoding are additional ways in which to better learn.

Acoustic encoding relates to sounds and their role in memory. This type of encoding relies on something known as phonological loops. Earlier, we discussed how saying things out loud helps us retain more information, and part of the reason behind that is phonological loops.

As we repeat concepts to ourselves repeatedly, we can remember them by starting to recite the initial words or parts of that concept. You can also connect your subject matter with things that you already know to facilitate better learning. This is also known as elaborative encoding, wherein your brain connects new information through old data that it already has.

As such, while dual encoding definitely has its advantages, you must also utilize the two other types of encoding for maximum learning, regardless of which topic you’re studying.