Phonetics of Tone (African Languages)

Most of the languages of Africa are tone languages, and the distribution of tones in these languages is often integrated into the morphology and syntax. Descriptions of tone in African languages have been influential in the development of linguistic approaches to tone and in particular autosegmental representations. But almost all of those descriptions are based on phonetic transcriptions, which are subjective and imprecise. Experimental phonetic investigations, based on objective measurements and quantitative analysis, have given new insight into old issues in this area. Phonetic research on tone is concerned with how tones relate to fundamental frequency (f0), what factors affect that relation, how tones are produced, and how listeners recognize tone categories. Such research on African tone languages has provided significant information about how tone categories can differ in f0 contour. It has yielded evidence about downdrift and downstep, two notions derived from the study of these languages. It has shown how intonation can work in a language in which tone is used to distinguish words. It has shed light on how tones can be realized in the face of interruptions of modal voicing. The small but growing body of experimental work on tone in African tone languages is significant because these languages make up a good proportion of the tone languages in the world, and because tone patterns in these languages have shaped how linguists look at tone.