Speech Prosody 2004
In informal English dialog many utterances are not composed of words, but are non-lexical items, such as uh-huh, um, and hmm. In non-lexical utterances much of the meaning is conveyed by prosody, rather than by the phonetic content. However the pragmatic functions of prosody in non-lexical utterances have not been much studied. Based on examination of 316 tokens in a conversation corpus, this paper identifies some common pragmatic functions for syllabification, duration, loudness, pitch height, pitch slope, and creaky voice in non-lexical utterances. While the evidence is eclectic and the investigation has been unsystematic, it seems that each of these prosodic features bears a fairly consistent core meaning.
Bibliographic reference. Ward, Nigel (2004): "Pragmatic functions of prosodic features in non-lexical utterances", In SP-2004, 325-328.