Overlearning
Overlearning refers to practicing newly acquired skills beyond the point of initial mastery. The term is also often used to refer to the pedagogical theory that this form of practice leads to automaticity or other beneficial consequences.
Early studies
Memory researcher Hermann Ebbinghaus performed classical overlearning studies in the late 1890s. He noticed that memory for learned material decreased over time, following the line of a "forgetting curve". Ebbinghaus recognized that lists of nonsense syllables became more difficult to recall over time, and some lists required more review time to regain 100% recall. He defined overlearning as the number of repetitions of material after which it can be recalled with 100% accuracy.Contemporary work
A 1992 meta-analysis suggested that overlearning does significantly affect recall over time. It also concluded that the size of this effect may be moderated by the amount of overlearning, task type, and length of retention. The meta-analysis included 15 studies. These 15 studies tested overlearning effects on physical and cognitive tasks. Both types of task showed an effect of overlearning. The effect size for physical tasks was smaller than the effect size for cognitive tasks. The amount of overlearning affected retention: more overlearning led to more retention on both types of task. The length of the retention interval also affected overlearning, but the effects were different for physical and cognitive tasks. Whereas participants overlearning physical tasks increased in ability during the retention interval, participants who overlearned cognitive tasks decreased in recall ability over time.Some recent studies explicitly examined the interaction of overlearning with retention interval, and concluded that the effects of overlearning tend to be fairly short-lived. Overlearning may be more useful in instances when learners only need short-term retention of the material.