Melodic characteristics of backchannels in Dutch map task dialogues

In natural conversation backchannels (short optional utterances like ‘uh-huh’ or ‘yes’) are used to indicate to the current speaker that the current listener understands so far and that the speaker may continue. The question posed in the present paper is whether backchannels distinguish themselves melodically from lexically identical utterances that have a different function (e.g., the answer to a question). In a corpus of Dutch Map Task dialogues the melodic configurations realized on all backchannels and all lexically identical non-backchannels were transcribed using ToDI [1]. Comparison of the two groups of data reveal a clear tendency for backchannels to be marked by a non-prominence lending drop in pitch followed by a high boundary tone (69%), whereas the non-backchannels generally carry a pitch accent (61%).