Processing Difficulty Effect

What is the Processing Difficulty Effect?

The processing difficulty effect, sometimes called the disfluency effect, is a label used for claims that harder-to-process information produces better later learning. Perceptual disfluency, such as a hard-to-read font, is one manipulation studied under this heading. Greater difficulty is not generally a guarantee of deeper understanding or better memory.

Hard-to-read fonts and learning

Findings for hard-to-read text have been mixed. A study pooling an original math-problem result with 16 replication attempts found no benefit in correct solutions. A later critique of a learning meta-analysis found its null transfer result relatively robust, while identifying problems with its recall and moderator analyses.

Processing difficulty in teaching and design

Making instructions complex or text hard to read should not be assumed to improve learning. Some carefully chosen challenges, including retrieval practice or spacing, can support retention under suitable conditions; these are distinct manipulations and require their own evidence. Learning, comprehension, accessibility, and time spent must be assessed separately. In advertising, remembering a difficult-to-read message would still be a different outcome from understanding it or deciding to buy.

Sources: Meyer and colleagues (2015); Weissgerber, Brunmair, and Rummer (2021).