Downdrift/declination

It has been observed by many researchers that there is often a gradual downdrift in the value of FO across a phrase [446], [447], [351], [107], [285], [167]. How downdrift (often referred to as declination) is dealt with by different theories varies widely. Ladd [267] gives a review of some of the different theories. 

Many treat downdrift as an automatic physiological effect arising from changes in sub-glottal pressure during the course of an utterance [287], [107]. This account gives the speaker little conscious control over declination. The approach of the Dutch School [446], has been to use three... 

A major claim of Pierrehumbert s thesis [351] was that more than one factor was responsible for the downdrift of FO contours. As with many other theories, she proposed that the phonetic declination effect exists, but also argued that the major contribution to the downdrift of utterances was downstep which was a phonological effect and therefore controllable by the speaker. Figure 9.8... 

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