We've all experienced the tip of the tongue moment where we wanted to say something but just couldn't remember the word. But what causes this momentary lapses in vocabulary?
Psychologist Jennie Pyers of Wellesley College in Massachusetts compared billinguals, monolinguals and people who are fluent in sign language to - what is that darned word ... elucidate - the possible cause of this phenomenon:
To provoke tip-of-the-tongue moments, the researchers showed the bilinguals, as well as a control group of 22 English monolinguals, pictures of dozens of different objects and challenged the volunteers to name them in 30 seconds. The viewed objects – which included axes, weathervanes, gyroscopes, nooses and metronomes – were obscure enough to elicit tip-of-the-tongue experiences in all but one participant.
As with previous experiments, monolinguals had fewer tip-of-the-tongue experiences than bilinguals, about 7 words versus 12, out of a total of 52 – though Pyers' team counted only instances where the volunteer knew the word.
However, Spanish bilinguals experienced roughly the same number of tip-of-the-tongues as sign language bilinguals. This rules out the possibility that similar-sounding words compete for our brain's attention in tip-of-the-tongue experiences.
More likely, tip-of-the-tongue experiences occur when we're trying to recall rarely used words, Pyers says.
"People often have tip of the tongue experiences for proper names, again because we don't use them very frequently," she adds.