Surely, you have seen a familiar face that you could not quite place, or perhaps you could not retrieve the person’s name. People often experience a feeling of knowing or familiarity in which some name, word, date, or other information cannot be retrieved despite a certainty that it is available in memory. When such feelings become particularly intense, psychologists refer to the experience as a tip of the tongue (TOT) state. Brown and McNeill (1966) studied such TOT states for words by giving people definitions of rare words and asking them to recall the words. Of interest, when people experienced a TOT state, they could correctly identify the number of syllables in the forgotten word more than 60% of the time. Further investigation (Brown, 1991) showed that “TOTs (a) are a nearly universal experience, (b) occur about once a week, (c) increase with age, (d) are frequently elicited by proper names, (e) often enable access to the target word’s first letter, (f) are often accompanied by words related to the target, and (g) are resolved during the experience about half of the time” (p. 204).
TOT states suggest that information may be available in memory but inaccessible. The forgetting seems to be clearly caused by a failure to find the right retrieval cue. Sometimes, we can successfully recall the forgotten information by stumbling on a thought or perception that triggers the memory. The principle of encoding specificity explains this as another example of cue-dependent forgetting. Numerous other experiments have documented the principle that the specific cues associated with an event during learning provide the key to later recall