Anticipatory tonal coarticulation: how, when and why it occurs

This study examines anticipatory tonal coarticulation exhibited on a string of neutral tones in Mandarin. In addition to the well-documented dissimilatory anticipation triggered by the Low tone, the results show that the Falling tone (with high onset) consistently exerts assimilatory anticipatory effect which could extend over three preceding neutraltone syllables; the High tone, on the other hand, doesn’t exert such effect. 2D density plots of the surrounding full tones revealed that dissimilatory anticipation was strongest when the neutral tones were both preceded and followed by a low pitch target, whereas assimilatory anticipation tended to occur when the following tone had an early high pitch target. This finding was interpreted as the result of speech planning and articulatory constraint.