Why Are Pictures Often Easier to Remember Than Words?

After studying a set of object cards, we often remember items presented as pictures better than items presented only as names. This is called the picture superiority effect. It does not mean that vision is somehow superior to words: reading also uses vision. What matters is how information is encoded and later retrieved.

Consider a photograph of an umbrella. It may leave visual features such as the curved handle and canopy, while also readily bringing to mind the word ‘umbrella’. Dual-coding theory proposes that these representations offer different routes into memory. Another account emphasises the distinctive visual features of pictures as a way of reducing confusion. No single experiment has settled the mechanism.

The limits matter too. In 1976, Nelson and colleagues manipulated how similar pictures were in shape. With highly similar pictures, the advantage disappeared and even reversed at the faster presentation rate. Remembering that an umbrella appeared is therefore different from recognising the original umbrella among many similar ones. Recalling its name may not be enough for the latter task.

These studies generally use controlled materials and particular memory tests. They do not directly establish that adding pictures improves understanding of every text. My judgement is that images should help us distinguish things and build connections, rather than merely decorate a page. There is a better case for an image that identifies its subject and preserves important differences than for adding a beautiful photograph to every sentence. Remembering the image still leaves us to check whether we understand what it is meant to explain.

https://pubmed.ncbi.nlm.nih.gov/1003125/
https://www.cmu.edu/dietrich/psychology/memorylab/publications/10.1.1.646.3474.pdf