Desirable Difficulties - Why "Difficulty" is Necessary in Learning In the science of learning, there's a term called "Desirable Difficulties," which refers to the cognitive efforts necessary in learning, researched by Robert and Elizabeth Bjork. In Chapter 5 of "Psychology and the Real World," the Bjorks list and compare learning techniques proven by science to be effective versus those mistakenly thought to be effective. These include:Spaced Learning (Spacing) versus Massed Learning (Massing...