Using Words with Visuals: Dual Coding as a Teaching Strategy


I’m exploring strategies from cognitive psychology that teachers of adults can use to enhance learning and improve outcomes in their behavior-change courses. Last time I explored spacing and retrieval practice. In this post I will take a look at dual coding.

Dual coding is pairing relevant images with words

Dual coding is a teaching strategy that involves using images with words to teach new content. Students can look at a visual while hearing a verbal explanation or they can view an image with written labels or descriptions.

Examples of dual coding include:

  • Diagrams
  • Timelines
  • Cartoons
  • Graphic organizers
  • Simple drawings with labels
  • Infographics

Dual coding involves co-locating words and visuals.

The key to successful use of dual coding is to keep the images simple and relevant and to co-locate words and images. Intricate images are not desirable. If there is too much detail in an image, the important points can get lost. For this reason photographs may not be as effective as a simple line drawing or diagram.

For presentations, relevant images can be shown on slides while the teacher provides a verbal explanation. Students look at the image and listen to the explanation. 

In the interest of holding attention and providing a memorable visual, I like to use a surprising but relevant image accompanied by narration. Below is an example that introduces the concept of productive struggle. The slide below illustrates the essence of productive struggle (what some call desirable difficulty) in a quirky but hopefully memorable way.


Students view the slide and hear the following narration introducing the concept of productive struggle:

Productive struggle is exactly what it sounds like. Learning activities that use productive struggle require students to wrestle a bit, figure things out, rather than have everything spoon fed to them. The learning literature tells us we remember what we work at better than what someone simply tells us. When students struggle and then figure something out it builds their efficacy expectations - their belief that they are capable of learning something, even when they must struggle to do so. By using activities with productive struggle we are not only facilitating the construction of specific topic-related knowledge, we are introducing rigor and nurturing the ability to think critically, an important executive function.

Dual coding works because it takes advantage of two channels for processing information.

Combining a visual with verbal (text or explanation) is effective because we have separate storage channels for each in our working memory. While separate, they work at the same time. When teachers use images that are congruent with a verbal explanation, students process the new content through both their visual and audio channels. This increases the likelihood they will remember what they’ve seen and heard because they have two ways to store and recall it.

Use dual coding in class with your adult learners.

1. Use simple drawings with co-located descriptions 

Following is an example of a set of activity handouts I created for a coached visitation parenting program for low literacy and trauma-impacted parents whose children were removed from their care. The targeted reading level was 4th grade and I wanted to keep writing to a minimum.

This lesson was on developing skills as an emotion coaching parent. An emotion coaching parent is one who notices and responds to his children’s emotions by naming and validating them and taking proactive, nurturing action in response to those emotions.

I wanted to have the parent compare and contrast an emotion coaching parent with the opposite - a dismissive parent - one who didn’t notice or respond supportively to his child’s emotions.

I created two diagrams, one to represent each parent. This is the emotion coaching parent diagram. 


This simple line drawing of a heart is the visual cue that will support what the coach will say and the text the parent will eventually add to this diagram using peel-and-stick labels. There is also a place below the diagram where parents will attach photos to further illustrate the text they will soon add. To manage cognitive load, visuals and the lines inside the heart where text will go are co-located, rather than separated out in a legend or on two separate pages.

Here is the image for the dismissive parent, also with a place for photos at the bottom and text on lines inside the heart. The visual cue is the jaggedly broken heart.


With just a brief introduction of the two types of parents using the descriptions above, the coach invites the parent to look at a sheet of peel and stick labels prepared with various parenting beliefs and actions written on them. The parent's task is to sort and apply each one to either the emotion coaching diagram or the dismissive diagram. The parent coach asks the parent if he would like to read them aloud or if he would like the coach to read them aloud. With either choice, the parent tells the coach where each belief and action should be placed and why he thinks so and then applies it to one of the two heart diagrams. 


The photos are on two labels and provide body language and facial cues that depict the impact of the two kinds of parenting. The parent applies the photos to the space beneath each heart diagram, matching the impact to its respective diagram and explaining why he has placed them where he has.

In this program, the conversation happens between the parent and the coach, but this could also work as a table or pairs activity provided someone at each table or within each pair was comfortable reading aloud.

Here is a completed set of handouts with the dual coding.


2. Ask students to diagram their understanding of how concepts relate to each other.

In the example below, I created a diagram to outline my understanding of the impact of trauma on the brain and the ability to learn after reading a couple of journal articles on the topic.


3. Ask students to illustrate written content or write descriptions of visual content.

In the Parenting Inside Out curriculum, after the teacher presents information on family roles, students use the handouts below to draw a representation of the impact of each role on the family and a brief description of the behavior of someone playing that role. Following are two completed student handouts using dual coding, one of the caretaker role and the other of the mascot/cheerleader role.


Manage cognitive load when using dual coding.

To make dual coding most effective, it is important to manage the total cognitive load for students. Avoid using too much, redundant, or unrelated information because all of this increases the cognitive load on learners, reducing the effectiveness of the strategy. Here are some guidelines for managing cognitive load when using dual coding.

  1. Avoid all decorative images or clip art that provides no meaningful elaboration of the content. It is distracting and overloads students’ visual channel.
  2. Co-locate the text with the image rather than using a legend or having the image on one page and the explanatory text on another page. Flipping back and forth to match up visuals with text splits attention and causes cognitive overload for learners.
  3. Do not read aloud printed text from your slides. Chances are students can read faster to themselves than you can read aloud. This also overloads the audio channel. A more effective approach is to have students look at a relevant vivid image or diagram while you explain a concept or process. Pairing narration with a relevant and easy to see visual with just the essential elements makes good use of learners' audio and visual channels, enhancing the chances they'll remember what they saw and heard.

My favorite example of dual coding is any 2-minute video by Robert Reich.

I have learned more about the economy and how our government functions from Robert Reich’s two-minute videos than I did in all my years of dreary text book readings in high school. Now that I know about dual coding, I can see why his videos are so effective. Here is a great example of effective dual coding in this 1-minute and 37 second video on 3 Economic Myths. Check out his masterful use of dual coding using simple explanation and relevant, spare drawings.

How do you use dual coding with your learners?

You've probably used dual coding even if you haven't heard of the term. I'd love for you to share how you do this using the comments section below.


Colvin Clark, R. (2010). Evidence-based training methods. Alexandria: American Society for Training and Development.

Dirksen, J. (2016). Design for how people learn. (2nd edition). Berkeley: New Riders.

Harvard, B. (2-7-17). Dual coding in the classroom. The Effortful Educator Blog. https://theeffortfuleducator.com/2017/02/07/dual-coding-in-the-classroom/ 

Smith, M. (11-7-16). Dual coding: Can there be too much of a good thing? The Learning Scientists Blog. http://www.learningscientists.org/blog/2016/11/17-1

Smith, M & Weinstein, Y. (9-1-16). Learn how to study using...dual coding. The Learning Scientists Blog. http://www.learningscientists.org/blog/2016/9/1-1