Despite the common fear that those annoying tip-of-the-tongue moments are signals of age-related memory decline, the two phenomena appear to be independent, according to findings published in Psychological Science, a journal of the Association for Psychological Science.
Anecdotal evidence has suggested that tip-of-the-tongue experiences occur more frequently as people get older, but the relationship between these cognitive stumbles and actual memory problems remained unclear, according to psychological scientist and lead author Timothy Salthouse of the University of Virginia:
"We wondered whether these self-reports are valid and, if they are, do they truly indicate age-related failures of the type of memory used in the diagnosis of dementia?"
To find out, Salthouse and Arielle Mandell - an undergraduate researcher who was working on her senior thesis - were able to elicit tip-of-the-tongue moments in the laboratory by asking over 700 participants ranging in age from 18 to 99 to give the names of famous places, common nouns, or famous people based on brief descriptions or pictures.
Throughout the study, participants indicated which answers they knew, which they didn't, and which made them have a tip-of-the-tongue experience.
Several descriptions were particularly likely to induce a tip-of-the-tongue moment, such as: "What is the name of the building where one can view images of celestial bodies on the inner surface of a dome?" and "What is the name of the large waterfall in Zambia that is one of the Seven Wonders of the World?" Of the pictures of the politicians and celebrities, Joe Lieberman and Ben Stiller were most likely to induce a tip-of-the-tongue moment.
Overall, older participants experienced more of these frustrating moments than did their younger counterparts, confirming previous self-report data. But, after the researchers accounted for various factors including participants' general knowledge, they found no association between frequency of tip-of-the-tongue moments and participants' performance on the types of memory tests often used in the detection of dementia.
"Even though increased age is associated with lower levels of episodic memory and with more frequent tip-of-the-tongue experiences...the two phenomena seem to be largely independent of one another," write Salthouse and Mandell, indicating that these frustrating occurrences by themselves should not be considered a sign of impending dementia.