Benedict Carey

Robert and Elizabeth Bjork called any technique that causes forgetting a ‘desirable difficulty,’ in that it forces the brain to work harder to dig up a memory or skill—and that added work intensifies subsequent retrieval and storage strength (learning).

If learning is building up skills and knowledge, then forgetting is losing some of what was gained. It seems like the enemy of learning. It’s not. The truth is nearly the opposite.

I no longer think of naps or knocking off early as evidence of laziness, or a waste of time, or, worst of all, a failure of will. I think of sleep as learning with my eyes closed.

If the brain is a learning machine, then it’s an eccentric one. And it performs best when its quirks are exploited.

To build and retain foreign vocabulary, scientific definitions, or other factual information, it’s best to review the material one or two days after initial study; then a week later; then about a month later.

More important than how long you study is how you distribute study time you have. Breaking up study or practice time—dividing it into two or three sessions, instead of one—is far more effective than concentrating it.

Interleaving. That’s a cognitive science word, and it simply means mixing related but distinct material during study.