Fundamental frequency and perceived prominence of accented syllables.

Perceived prominence differences between accented words have been accounted for in terms of fundamental frequency (F0) variations. In one theory prominence is related to the relative magnitude of F0 changes, and in another theory prominence is related to relative frequencies of F0 maxima. Two experiments with the same group of subjects contrasted the two theories. The experiments used reiterant speech consisting of "maMAmamamaMAma" utterances with synthesized F0 contours, with F0 maxima on the second and penultimate syllables (P1 and P2, respectively). In one experiment the utterances had no baseline declination, and in the other experiment the slope of the baseline was varied. In both experiments, subjects performed an adjustment task under two different instructions: They were instructed to adjust P2 so that it had the same pitch or prominence as P1. The results show that both variables (instruction and presence or absence of baseline declination) affect the adjustments of P2. It is concluded that neither theory gives a satisfactory account of the results, and that perceived prominence is related in a complex way to the range of F0 values employed.