Nuclear Pitch Accent Research Articles

The nature and use of Icelandic prenuclear and nuclear pitch accents: Evidence from F0 alignment and syllable/segment duration

Two production studies and one perception study were designed to systematically test F0 alignment and segment duration in Icelandic pitch accents with a view to investigating previous claims about the inventory of distinct intonational categories. Four different conditions were tested: (i) prenuclear pitch accents, (ii) nuclear accents in sentence-final position in sentences with either broad focus or (iii) with final narrow focus, and (iv) nuclear narrow focus accents in non-final position. The alignment results are such that (i) prenuclear accents are signalled by a late rise (L*H), while final nuclear accents are signalled by an early rise; (ii) F0 peaks in prefinal nuclear accents are aligned earlier than in prenuclear accents, but later than in final nuclear accents, suggesting a prosodic boundary effect. The duration measurements suggest a positional, but no focus, effect on the duration of the accented syllable and its vowel, such that syllables/vowels earlier in the sentence are longer than later ones.

Miami Cuban Spanish Declarative Intonation

Abstract The current study is a phonetic description and phonological analysis, using the Autosegmental Metrical (AM) theory of intonational phonology, of broad focus (neutral) declarative utterances in the Spanish of three generations of Miami Cubans. No differences were found across these three generations indicating the maintenance of a robust intonational pattern for declarative utterances. The prenuclear (non-final) pitch accent is analyzed to be L*+H and the nuclear pitch accent is L+H*. This phonological analysis is similar to what has been found for many other varieties of Spanish. A high rate of deaccenting, however, was observed in conjunction with the final lexically stressed syllable. The prevalence of deaccented final stressed syllables is unique to what has been found for other Spanish varieties.

Projective vs. interpretational properties of nuclear accents and the phonology of contrastive focus in Greek

Nuclear accents have two interesting properties. First, they have a projective property, i.e., they may refer to a focus domain that encompasses a higher syntactic projection. Second, at least for some languages, nuclear accents may have an interpretational property, i.e., they may have alternative realizations that reveal particular interpretations, such as contrast, correction, surprise, etc. The present article examines the interaction between the projective and the interpretational properties of nuclear pitch accents. Based on an experimental study on Greek, we show that the nuclear accent that is interpreted as ‘contrastive’ refers to a local focus domain, i.e., it is not projected to higher layers of the constituent structure. Furthermore, our experimental findings show that these properties interact with syntactic and prosodic markedness, in a way that the canonical word order and the unmarked accentual structure are felicitous in a larger array of contexts than the marked syntactic and accentual configurations.

On the acoustic correlates of high and low nuclear pitch accents in American English

Earlier findings in Shue et al. (2007, 2008) raised questions about the alignment of nuclear pitch accents in American English, which are addressed here by eliciting both high and low pitch accents in two different target words in several different positions in a single-phrase utterance (early, late but not final, and final) from 20 speakers (10 male, 10 female). Results show that the F 0 peak associated with a high nuclear pitch accent is systematically displaced to an earlier point in the target word if that word is final in the phrase and thus bears the boundary-related tones as well. This effect of tonal crowding holds across speakers, genders and target words, but was not observed for low accents, adding to the growing evidence that low targets behave differently from highs. Analysis of energy shows that, across target words and genders, the average energy level of a target word is greatest at the start of an utterance and decreases with increasing proximity to the utterance boundary. Duration measures confirms the findings of existing literature on main-stress-syllable lengthening, final syllable lengthening, and lengthening associated with pitch accents, and reveals that final syllable lengthening is further enhanced if the final word also carries a pitch accent. Individual speaker analyses found that while most speakers conformed to the general trends for pitch movements there were 2/10 male and 1/10 female speakers who did not. These results show the importance of taking into account prosodic contexts and speaker variability when interpreting correlates to prosodic events such as pitch accents.

Nuclear Pitch Accents in Majorcan Catalan Declaratives: Phonology, Phonetics, Diachrony

Abstract The present paper reports on the findings of an acoustic study of nuclear pitch accents in Majorcan Catalan. A total of 10 speakers participated in a production experiment. Nuclear pitch accents were investigated by measuring relative pitch changes between several sequential temporal landmarks in and around nuclear stressed syllables in read-aloud declaratives. The results provide evidence for the presence of a low (L) tone associated with the nuclear stressed syllable for 9 of the 10 participants, and that of a high (H) trailing tone for only 4 of the participants. The implications of these results for a phonological analysis of Majorcan Catalan nuclear pitch accents, as well as the diachrony of nuclear pitch accents in Iberian Romance, are discussed.

Você está pedindo ou perguntando? Uma análise entonacional de pedidos e perguntas no português do Brasil

In this paper the intonation contours of yes/no questions and requestsin Brazilian Portuguese are compared. Speech synthesis was used toevaluate the relevance of the F0 configuration of nuclear andprenuclear pitch accents in the distinction between these twointonational patterns. Thirty-one resynthesized melodic versions ofthe sentence “Na festa destranca?” (At the party do you unlock it?/At the party would you please unlock it?) – which is ambiguous inPortuguese in its interpretation as a question or as a request – havebeen created. These versions, placed in four auditory tests, havebeen judged by twenty listeners who evaluated the effects of themodifications in the original sentence, in favor of its interpretationeither as a question or as a request. The results of the perceptiontests show that the opposition between the two melodic contours isdue to the direction of the F0 curve in the nuclear pitch accent,rising in the yes/no question and falling in the request. A phonologicalrepresentation of these patterns, based on distinct temporal alignmentsof the F0 peak in the final stressed syllables, is proposed.

The Analysis of Low Accentuation in Estonian

In Estonian, as in a number of other languages, the nuclear pitch accent is often low and level. This paper presents two studies of this phenomenon. The first, a phonetic analysis of carefully structured read sentences shows that low accentuation can also spread to the prenuclear accents in an intonational phrase. The resulting sentence contours are used as evidence to evaluate alternative phonological analyses of low accentuation, and H + L* is shown to account best for the data. The second study presents quantitative evidence from fundamental frequency values which supports this phonological analysis. Finally, the distribution of prenuclear pitch accents is discussed. High and low accents can co-occur in an intonational phrase, but only in patterns obeying a specific sequential constraint. A fragment of an intonational grammar for Estonian is presented capturing the observed distributional restrictions.

Utterance Signaling and Tonal Levels in Dominican Spanish Declaratives and Interrogatives

This paper examines the tonal patterns of sentences in Dominican Spanish produced in response to three pragmatic intents: declaratives, absolute interrogatives, and pronominal interrogatives. The results indicate that there are systematic variations between the three utterance types; however, the final tonal rise was not a determining factor. Distinct patterns of tonal levels distinguished each of the three utterance types. The pronominal interrogatives demonstrated a higher initial tonal value and prenuclear High tone, while the absolute interrogatives presented a significantly higher tonal value for the nuclear pitch accent. These findings identify specific intonational behaviors that vary across dialects of Spanish. Finally, the data indicate that pragmatic utterance level intonational marking of Spanish interrogatives is not limited to boundary tones as was previously suggested in the literature.

Declination of subglottal pressure during speech and its relation to tone distribution

The subglottal pressure contour Ps for speech is considered to have three phases: initiation (rapid rise), working (level or slightly declining), and termination (rapid fall). The current work focuses on characterization of the working phase in terms of the distribution of pitch accents and of phrase and boundary tones. In particular, the degree of Ps declination is studied. A measure of Ps declination has proven difficult to define [cf. Strik and Boves, J. Phonetics 23, 203–220 (1995)]. Therefore, in pilot work, subjective ratings of degree of declination are made on a subset of a corpus in which the tone distribution is controlled. Significant variation in the degree of declination is observed among speakers. For example, Ps for one speaker is relatively constant to slightly declining, while for another it is almost always sharply declining. For some speakers utterances with an early‐occurring nuclear pitch accent (NPA) show greater degree of declination than utterances with a late‐occurring NPA, as do utterances ending with high tones. Data for additional subjects and objective measures will be presented. The results have implications for models of speech production, and for applications such as computer speech synthesis and recognition. [Work supported by NIH Grants DC00075 and DC04331.]

Final lowering in non-final position

This article argues that a factor contributing to final lowering in intonation is that H tones preceding downstep are scaled higher than H tones not preceding downstep, all else being equal. Final lowering is argued to be (in part) the absence of this effect with the last element of a sequence of downstepped tones. The evidence comes from intonation data recorded with speakers of German from Southern Germany and Austria. In two structures, a sequence of downstepped prenuclear pitch accents PA 1!PA 2…!PA n−1 is continued with a nuclear pitch accent PA n that is not downstepped. In both structures, final lowering is found on the last downstepped pitch accent PA n−1 , crucially in penultimate position of the intonation phrase. Here potential triggers for final lowering in the environment are not present (phrase-final position) or present only in one structure (a following L% boundary tone). The application of final lowering in these cases shows that there is a factor contributing to final lowering that affects accentual tones not followed by downstep, regardless of the environment.

Tonal structure and pitch targets in Italian focus constituents

Aquest article investiga l’estructura tonal de l’accent focal de les oracions declaratives amb focus estret en italià de Nàpols. Les propietats formals de l’accent focal es podrien en principi analitzar de dues maneres possibles, bé com un accent tonal HL de tipus descendent o bé com un accent tonal LH de tipus ascendent. Les dues possibles anàlisis són avaluades en funció del comportament de l’accent tonal en constituents que contenen un nombre variable de mots. Els constituents focalitzats presenten una vall d’F0 que es comporta com un clar objectiu entonatiu. Aquest punt d’inflexió podria ser part també d’un accent HL o LH. Indicis tonals i temporals donen suport a la hipòtesi que es tracta d’un accent tonal ascendent. D’aquesta anàlisi se’n deriva el fet que el moviment tonal descendent final de les oracions declaratives s’ha d’analitzar com un gest tonal diferent de l’accent nuclear i que aquest es comporta de forma anàloga al to de frontera ascendent final de les oracions interrogatives.

Prosodically conditioned strengthening and vowel-to-vowel coarticulation in English

The goal of this study is to examine how the degree of vowel-to-vowel coarticulation varies as a function of prosodic factors such as nuclear-pitch accent (accented vs. unaccented), level of prosodic boundary (Prosodic Word vs. Intermediate Phrase vs. Intonational Phrase), and position-in-prosodic-domain (initial vs. final). It is hypothesized that vowels in prosodically stronger locations (e.g., in accented syllables and at a higher prosodic boundary) are not only coarticulated less with their neighboring vowels, but they also exert a stronger influence on their neighbors. Measurements of tongue position for English /a i/ over time were obtained with Carsten's electromagnetic articulography. Results showed that vowels in prosodically stronger locations are coarticulated less with neighboring vowels, but do not exert a stronger influence on the articulation of neighboring vowels. An examination of the relationship between coarticulation and duration revealed that (a) accent-induced coarticulatory variation cannot be attributed to a duration factor and (b) some of the data with respect to boundary effects may be accounted for by the duration factor. This suggests that to the extent that prosodically conditioned coarticulatory variation is duration-independent, there is no absolute causal relationship from duration to coarticulation. It is proposed that prosodically conditioned V-to-V coarticulatory reduction is another type of strengthening that occurs in prosodically strong locations. The prosodically driven coarticulatory patterning is taken to be part of the phonetic signatures of the hierarchically nested structure of prosody.

Intonational phonology description of Porteno Spanish

In this study the intonational patterns of Porteno Spanish (PS) are described within an Autosegmental Metrical (AM) (Ladd, 1996) approach. Porteno Spanish is the Spanish spoken in Buenos Aires, Argentina, and because of the influence from Italian and other languages, it differs markedly from varieties of Spanish that have been previously described. Six monolingual PS speakers were recorded saying 99 sentences which include declaratives, interrogatives, imperatives, and focused declarative and interrogative sentences. A ToBI framework, based on the F0 contour, was developed for labeling the sentences intonation. Preliminary results suggest that each phrase contains a somewhat regular pattern: (1) the stressed syllables of content words carry one of five pre-nuclear pitch accents, (2) nuclear pitch accents are more restrictive and tend to vary depending on the sentence type, and (3) boundary tones, both intermediate and intonational, are regular but also vary depending on sentence type.

Upstep and embedded register levels

This article is concerned with an interesting upstep phenomenon in the intonation of some speakers of Southern dialects of German. It experimentally establishes the main properties of this upstep phenomenon, and discusses the theoretical consequences. The upstep occurs on the nuclear pitch accent of a non-final intonation phrase. It targets the phonetic height of the utterance-initial peak, regardless of downstepped peaks that intervene between the initial peak and the upstepped peak. The findings are argued to provide unexpected support for a model of intonation in which downstep among accents can be embedded inside downstep among larger prosodic domains (Ladd 1988, van den Berg et al. 1992). In a combination of that model with an extension of Pierrehumbert & Beckman (1988), it is suggested that the choice between downstep and upstep is conditioned by association to higher prosodic constituents in a systematic way.

Articulation of word and sentence stress

This paper reports on the articulation of two aspects of speech prosody: word and sentence stress. Word stress is examined in reiterant renditions of minimal pairs differing in the location of main stress (e.g., DIScharge–disCHARGE), with the contrastive stress difference manifested as differences in the location of the nuclear pitch accent. Sentence stress is examined in sets of minimal sentences differing in the presence or location of the nuclear pitch accent (e.g., so TOMMY gave Debby a song from Timmy). Three talkers read these materials while movements of the jaw and tongue (using the Carstens Articulograph) or of 20 reflective infrared markers on the face (using the Qualysis Motion Capture system) were recorded. Syllables with and without contrastive pitch accents are compared along several articulatory dimensions, including: jaw displacement and duration of movement, jaw peak opening and closing velocities, jaw peak acceleration, whole head displacement, and eyebrow displacement. These comparisons allow us to determine whether the talkers articulate the focused syllables/words differently. The three talkers were selected to differ in their overall visual speech intelligibility, as rated by expert deaf speechreaders, and therefore interspeaker differences in articulation are expected. [Work supported by NSF KDI Grant 9996088.]

Boundary tones and focus realization in African American English intonations

Intonation of African American English (AAE) has been impressionistically described as having a final level rising and an early rise contour different from that of mainstream American English (MAE) [Tarone (1972)]. But to our knowledge, no systematic description of AAE intonation has been done based on phonetic experiments. In this study, tone patterns occurring at the final edge (nuclear pitch accent, phrase tone, and boundary tone) of different sentence types were examined. Tonal patterns were compared based on the framework of Pierrehumbert and her colleagues [Pierrehumbert, 1980]. In addition, the location of focus was varied to examine how focus interacts with the early rise or final level rise in AAE. Three dialogue sets acted out by female speakers of AAE and MAE were recorded. Preliminary results show that both groups use the same final edge tone patterns for declaratives and wh-questions, but different patterns for yes/no questions (L*, H-, upstepped H% for MAE vs H*, H-, level H% for AAE) and vocatives. For focused sentences, AAE very often added postnuclear pitch accents when nonfinal words were focused. Furthermore, AAE used a sharp final fall preceded by a high tone (H+L*L−L*) when they have a negative attitude toward the sentence or situation.

The intonational structure of Chickasaw

Relatively little instrumental work has been done on the intonational structure of American Indian languages. This study investigates the intonation of Chickasaw, an American Indian language belonging to the Muskogean family, following Pierrehumbert’s [The Phonology and Phonetics of EnglishIntonation (MIT, Cambridge, MA, 1980)] intonation framework. Preliminary results suggest certain interesting intonational features in Chickasaw. Declarative intonational phrases with neutral subject–object–verb word order are marked with a high boundary tone, whereas interrogative intonational phrases are signaled with a low boundary tone. In both types of phrases, a high nuclear pitch accent docks onto the right-most heavy syllable in the verb, where heavy is equivalent to CVV, CVC, or CV in a metrically prominent position. Data also show that an intonational phrase in Chickasaw consists of one or more accentual phrases. Accentual phrases consisting of a single word begin with a low tone, and receive a high tone both on the second syllable and the final syllable of the phrase: LHH pattern. The initial low tone of the accentual phrase is typically not realized in words with fewer than three syllables. Accentual phrases consisting of more than one word and the effect of focus on intonation will also be considered.

Timing differences between prenuclear and nuclear pitch accents in Italian

In Italian, as in English, lexically stressed syllables can receive a pitch accent, with the last accented syllable being the most prominent (i.e., ‘‘sentence stress’’). Recent analyses based on data from northern Italian varieties describe the nuclear accent of the neutral declarative contour as falling onto the stressed syllable (H+L*), while the prenuclear one, presenting a comparatively later peak, is described as qualitatively different from the other (H*). This analysis is problematic since there is no meaning contrast between H* and H+L*. An alternative analysis of the timing differences models the shape of both accents as H*, where the high in the nuclear one is retracted due to an upcoming low tone associated with the remaining of the utterance (tonal repulsion hypothesis). A similar account has been proposed for English H* by Silverman and Pierrehumbert. This analysis predicts that the timing differences will depend on such things as the number of following stressed syllables for the L-, and also that other pitch accent types (such as the L*+H of the question) will show comparable differences. The analysis was tested by measuring the location of the fundamental frequency peak relative to the beginning of the stressed vowel in various prosodic contexts.

Some phrase-level influences on the glottal waveform

The prosody of an utterance is often described in terms of the locations of attributes such as pitch accents, boundary tones, and vowel reduction. These prosodic descriptions are usually represented in the sound by changes in fundamental frequency, duration, and other temporal and spectral attributes of the segments. This paper presents data showing that the amplitude and spectrum of the glottal pulses, as well as their frequency, undergo modification depending on locations of pitch accents and boundary tones and depending on vowel reduction. The following results were obtained: (1) Reduced vowels tend to have significantly lower amplitude (7 to 13 dB) than nonreduced vowels, together with an increased first-formant bandwidth and an increased tilt in the source spectrum; (2) a nonreduced vowel has a somewhat reduced amplitude (by about 6 dB) when it follows a nuclear pitch accent; and (3) a nonreduced vowel in utterance-final position in a declarative sentence shows a decreased amplitude of the first-formant peak, an increased open quotient, and an increased spectrum tilt. Production mechanisms that could account for these changes include modifications in subglottal pressure, adjustments of the glottal configuration, and influences of constrictions in the supraglottal airway. [Work supported in part by a grant from NIDCD.]

The articulatory kinematics of accent

Two recent kinematic studies of syllables with bilabial consonants suggest different dynamic accounts of the durational increase associated with stress: Kelso et al. [J. Acoust. Soc. Am. 77, 266–280 (1985)] interpret regression curves for peak velocity against displacement as evidence that lower-lip gestures in stressed syllables are less stiff, whereas Nittrouer et al. [J. Acoust. Soc. Am. 85, 1653–1661 (1988)] show that the upper-lip closing gesture begins at a later phase relative to the jaw opening gesture. Preliminary results from a kinematic study of accented syllables suggest a resolution of the discrepancy. Jaw opening and closing gestures for pop and poppa embedded in sentences that varied the placement of the nuclear pitch accent (sentence stress) were looked at. When accented, gestures were substantially longer, but the velocity-displacement regression curve showed no decrease in slope, contra Kelso et al. Also, a comparison of observed syllable durations to those predicted by the velocity-displacement ratios showed that this stiffness index alone cannot account for the greater length. Rather, an accented syllable is longer probably because the closing gesture is later, in accordance with Nittrouer et al. The seemingly contradictory pattern in Kelso et al. may be an artifact of including reduced syllables with unaccented full syllables in a single “unstressed” category. [Work supported by the NSF.]