Research finds people retain more material when it is hard to read

Mistakes in judging what we know . . . are partly rooted in simple biases. For instance, most people assume when studying that newly learned facts will long be remembered and that further practice won’t make much difference. These beliefs are subconscious and automatic, studies find, even though people know better when they stop to think about it.

One reason for this has to do with a cognitive quality known as fluency, a measure of how easy a piece of information is to process. The brain automatically associates perceptual fluency, or ease of storage, with retrieval fluency, ease of recall. This is a good rule of thumb for lots of new facts. . . [b]ut it’s not as good a guide when studying difficult concepts that don’t fall easily into a person’s areas of expertise or interest.

“For example, we know that if you study something twice, in spaced sessions, it’s harder to process the material the second time, and people think it’s counterproductive,” said Nate Kornell . . . “But the opposite is true: You learn more, even though it feels harder. Fluency is playing a trick on judgment.”

Is acquiring fluency in a language similar to learning difficult concepts? It isn’t for me, but may be for some.