We have all experienced that “tip-of-the-tongue” feeling.  You know, the one where you know you know something, but you just can’t quite remember it at the moment?  The reason you experienced the feeling is probably that it had been a bit too long since you had thought of the given fact (perhaps because it was a very rare word or name).  Although feeling can sometimes be quite disconcerting, it does have a very positive benefit:  Once you are finally reminded of the correct answer, you will probably never forget it again!

This substantial memory-retention benefit is the central premise behind confidence-based repetition (CBR), a term coined by the learning experts at Brainscape.  CBR uses your own confidence ratings to space each exposure in the optimal interval of time: research shows that the optimal interval of spaced repetition is the longest amount of time before you would have otherwise forgotten the concept (Bahrick & Phelps, 1987).  Using CBR to determine the repetition interval for each concept results in the most efficient use of study time for a given subject. (more…)