The Challenge of Non-lexical Speech Sounds

Nigel Ward

International Conference on Spoken Language Processing, 2000

Abstract:
Non-lexical speech sounds (conversational grunts), such as
\da{uh-huh}, \da{un-hn}, \da{mm}, and \da{oh}, are common in English.
In human dialogs these sounds are important in conversation control
and for conveying attitudes.  Spoken dialog systems may make use of
these sounds to achieve concise, smooth, relaxed interactions.  Doing
so is, however, a challenge, because most algorithms used in spoken
language processing were devised for words, but grunts are different
from words both phonetically and semantically.  For example, the
phonetic inventory is different, superimposition of phonemes occurs,
the set of conversational grunts is productive rather than finite, and
the meanings are compositional and involve sound-symbolism.