Mental Imagery and Memory: Why Vivid Pictures Stick

Two ideas: dual coding and picture superiority

Dual coding theory describes memory in terms of associative processes that work on a network of two kinds of representation: verbal ones (words) and nonverbal ones (images). Clark and Paivio reviewed the theory and its use in education. They report that concreteness, imagery and verbal associative processes play major roles in the learning and memory of school material (Clark and Paivio, 1991). The idea in plain words (our paraphrase): a word you can also picture may reach memory by two linked routes.

The picture superiority effect is a finding, not a theory. In four experiments, Standing found that pictures were remembered better than words on recognition and free-recall tasks. He described recognition memory for pictures as almost limitless under appropriate conditions, and the picture advantage held when the recognition task was made harder (Standing, 1973).

Together these ideas give a plausible background for why mnemonics ask you to build a picture. They do not prove that any one technique works, because neither source tested a mnemonic method.

What pictures do not do

The same 1973 abstract also reports faster retrieval for verbal material than for pictures. Pictures were not better at everything, and that is why we do not claim that drawing or visualizing always beats words for classroom learning.

A major review of ten study techniques is more cautious still. It rated imagery for text learning, along with the keyword mnemonic, as low utility, and it judged that the keyword mnemonic appeared to help for a limited number of materials and short retention intervals (Dunlosky et al., 2013). Reading a chapter while forming pictures is a different job from linking a name to a face.

Abstract ideas are the hardest case. A word such as fairness has no obvious picture, and Clark and Paivio point to concreteness as one of the factors that matter. If a stand-in image helps, such as a pair of scales for fairness, keep it simple. If it does not, explain the idea in words or sketch a diagram instead. The stand-in tip is practical advice, and the studies we cite did not test it.

Four moves for images you can recall

These moves are practical advice, not findings. The studies we cite did not test them one by one, so treat them as things to try and check against your own recall.

• Make it act. Give the pair something to do together, such as climbing, spilling or crashing.
• Change the size. Make one part huge or tiny, so the scene stands out from ordinary ones.
• Put yourself or someone you know in it. A picture with your own kitchen or your own friend is already tied to what you know.
• Add a sense. Imagine a sound, a smell or a texture, and keep the picture to one main event.

The keyword method turns this skill into a two-step recipe for foreign words, which you can see in the keyword method guide. The memory palace uses the same pictures but fixes them to places, as shown in the memory palace how-to.

A five-minute image test: build today, check tomorrow

Pick six concrete items, link them in three pairs, and see what you recall tomorrow. Before you close each image, run it through this checklist.

• Is something moving or changing in the picture?
• Is one part bigger, smaller or odder than in real life?
• Are you, or someone you know, in the scene?
• Can you say exactly where it happens?
• Can you describe it in one short sentence?

Tomorrow, say the first item of each pair and see whether the second one arrives. If it does not, rebuild that image with a stronger action. Add the pairs to Practice so they come back on a schedule. A longer chain of images is the subject of the story method, and the broader limits are in when mnemonics fall short.

Common mistakes

• Placing two objects side by side and calling it an image. Have the two interact in one action. Two items that merely sit together give you less to hold onto.
• Building a scene with too many details. Keep one main event per image. If you cannot describe it in one sentence, simplify it.
• Using borrowed images that mean nothing to you. Use your own rooms, friends and objects. A picture that is already tied to your life is easier to hold, in our practical judgment.
• Forcing pictures onto abstract ideas that you need to understand. Explain the idea in your own words or draw a simple diagram. Keep pictures for concrete items.

Frequently asked questions

What is dual coding?

It is a theory that memory uses two linked kinds of representation: verbal ones and imagery ones. Clark and Paivio (1991) review it and its uses in education. It is a framework for thinking about memory, and it does not test any one study technique.

Do pictures really beat words for memory?

In Standing's laboratory experiments, pictures were remembered better than words on recognition and free recall (Standing, 1973). The same abstract reports faster retrieval for verbal material, and the studies do not show that visualizing always beats words in class.

Can I use imagery to study a textbook?

Be careful. A major review rated imagery for text learning as low utility (Dunlosky et al., 2013). Pictures suit concrete items such as names and objects, in our practical view. For understanding a text, the same review rated practice testing as high utility, so testing yourself is a better place to start.

What if I cannot picture things clearly?

Keep the image simple, or lean on another hook such as a rhyme or an acrostic. People differ, and a rough, silly picture can do the job without being sharp.

Sources

We opened each source below before citing it. See Methodology and Sources for how we check them.

1. Clark, J. M., & Paivio, A. (1991). Dual coding theory and education. Educational Psychology Review, 3(3), 149-210. Open the source
2. Standing, L. (1973). Learning 10000 pictures. Quarterly Journal of Experimental Psychology, 25(2), 207-222. Open the source
3. Dunlosky, J., Rawson, K. A., Marsh, E. J., Nathan, M. J., & Willingham, D. T. (2013). Improving Students' Learning With Effective Learning Techniques: Promising Directions From Cognitive and Educational Psychology. Psychological Science in the Public Interest, 14(1), 4-58. Open the source