Tip of the fingers syndrome

We’ve all had that ‘tip of the tongue’ feeling when we’re sure we know the word or name for something but we just can’t think of it. Now a study has shown that a similar phenomenon occurs in American Sign Language (ASL), in what the researchers dub a ‘tip of the fingers’ experience.

Robin Thompson and colleagues at the University of California asked 33 deaf signers to name 20 pictures of famous faces, and then to translate a list of fairly obscure English words, including names of cities and countries, into ASL.

In ASL, many famous names are ‘finger spelled’, with a different hand-shape spelling out each letter of the name. For the famous faces task, 21 of the participants experienced 55 instances of a ‘tip of the finger’ syndrome between them, in which they were sure they knew the name but couldn’t spell it out. As in spoken language, in which people can often only think of the first letter of a word, the participants here were often able to sign the first letter but no more.

Most other words and proper nouns in ASL are represented by a precise combination of hand-shape, location, orientation and movement. When it came to translating obscure English words, 13 of the participants reported 24 instances of ‘tip of the finger’ experiences between them. This often manifested as an ability to recall one or more of the correct hand-shape, location, orientation or movement, but a failure to recall all these aspects, which is needed to communicate the word correctly. This mirrors the way speakers can often recall the first letter, the number of syllables, length, or certain sounds of a word they are struggling to think of.

With spoken language, ‘tip of the tongue’ syndrome is considered to show that word meaning and word form are represented separately in the mind. The authors said their study shows a similar situation pertains in sign language and helps dispel the common misconception that Sign is a form of complex pantomime in which intended meaning and Sign form are always related.

Thompson, R., Emmorey, K. & Gollan, T.H. (2005). “Tip of the fingers” experiences by deaf signers. Psychological Science, 16, 856-860.

Post written by Christian Jarrett (@psych_writer) for the BPS Research Digest.