The Shape of Nuclear Falls and their Effect on the Perception of Pitch and Prominence: Peaks vs. Plateaux

Abstract

This is the unspecified version of the paper.This version of the publication may differ from the final published version. Permanent repository link ABSTRACTThis paper investigates the perceptual effect of a high plateau in the intonation contour.Plateaux are flat stretches of contour and have been observed associated with high tones in Standard Southern British English (SSBE). The hypothesis that plateaux may make the accents with which they are associated sound higher in pitch than sharp peaks of the same maximum frequency is tested experimentally. In the first experiment listeners heard pairs of resynthesized utterances where the nuclear accent differed only in shape, not frequency. They indicated which stimulus they thought contained the higher pitched accent. Results showed that plateau-shaped accents sound higher than peaks. In the second experiment the effect of a plateau on prominence relations within an utterance is investigated. Listeners heard resynthesized sentences, and compared two accents. One group indicated which accent sounded higher in pitch and the other indicated which sounded more prominent. Results again indicated that plateau-shaped accents sound higher in pitch and also more prominent; judgements of pitch and prominence were very similar to one another. The results from both experiments indicated that accent shape is a perceptually important variable, although such a fine level of detail is not taken into account by autosegmental-metrical theories of intonation.

Tonal Center of Gravity: A global approach to tonal implementation in a level-based intonational phonology

“…Though some TPs are plainly visible in the F 0 record, in other cases the precise locations of F 0 TPs can be e xtremely ambiguous, so that no single point in the contour stands out from the others in such a way as to be straightforwardly identified as the 'target' in question. This problem is well-known from the case of high accentual plateaux (D'Imperio 2000; Knight 2008), and arises particularly frequently in the case of Low tone specifications as well. Often, for example, instead of an easily isolable F 0 m inimum flanked by sharp falling and rising regions, what we find are extended low regions, bounded by shallow rises or falls, such that neither a unique minimum, nor any clear inflection point demarcating movement offsets or onsets, can be identified.…”

“…These include: 'peak' shape (i.e., sharp peak vs. plateau: 't Hart 1991;D'Imperio 2000: 167-170;Knight 2008); rise or fall duration (in particular, cases in which the TPs in question do not correspond to any of the tonal targets normally thought to 'constitute' the F 0 events in question, e.g., the end of the fall following an L*+H pitch accent, or the beginning of the rise preceding an H*+L: D'Imperio 2000: 175-176; Niebuhr 2007a); pitch movement curvature (e.g., Welby 2003;Dombrowski and Niebuhr 2005;Barnes et al 2010b); and the relative frequency scaling of pitch movement onsets and offsets (D'Imperio 2000: 178). We review each of these problems in more detail in Section 3.…”

“…Differences in the perceived scaling of pitch accents implemented as sharp peaks, and those realized with an extended region around the maximum (known as 'plateaux') are well-documented ('t Hart 1991; D'Imperio 2000; Knight 2003Knight , 2008: all things being equal, a plateau-shaped accent sounds higher in pitch to listeners than an a ccent with sharp peaks at the identical maximum F 0 . This result already suggests something more complex occurring in perception than the simple extraction of the location in F 0 space of a single TP.…”

An enhanced autosegmental-metrical theory (AM+) facilitates phonetically transparent prosodic annotation

“…Viewed in this way, a syllable which is autosegmentally associated with a H tone naturally maps in most speaking situations to an F0 peak. However, since tonal targets are intrinsically perceptual in nature, other F0 mappings are possible, such as F0 plateaux [21,31] or variations in the F0 shape as given by e.g., tonal center of gravity [32,33]. AM + thus provides a unifying explanation for observed correspondences between abstract tones and their typical F0 consequences, cf.…”

Pointed and plateau-shaped pitch accents in North Frisian

“…It is known from the experiments of Knight (2008) that plateaushaped peaks do sound higher than pointed peaks with the same physical F 0 range/level, and Knight concludes on this basis that "it is possible that a plateau can also be used as a substitute variable for high F0" (p. 242).…”