Publications

Prosodic Structural Effects on Non-Contrastive Coarticulatory Vowel Nasalization in L2 English by Korean Learners

This acoustic study explores how Korean learners produce coarticulatory vowel nasalization in English that varies with prosodic structural factors of focus-induced prominence and boundary. N-duration and A1-P0 (degree of V-nasalization) are measured in consonant-vowel-nasal (CVN) and nasal-vowel-consonant (NVC) words in various prosodic structural conditions (phrase-final vs. phrase-medial; focused vs. unfocused). Korean learners show a systematic fine-tuning of the non-contrastive V-nasalization in second language (L2) English in relation to prosodic structure, although it does not pertain to learning new L2 sound categories (i.e., L2 English nasal consonants are directly mapped onto Korean nasal consonants). The prosodic structurally conditioned phonetic detail in English appears to be accessible in most part to Korean learners and was therefore reflected in their production of L2 English. Their L2 production, however, is also found to be constrained by their first language (L1-Korean) to some extent, resulting in some phonetic effects that deviate from both L1 and L2. The results suggest that the seemingly low-level coarticulatory process is indeed under the speaker's control in L2, which reflects interactions of the specificities of the phonetics-prosody interface in L1 and L2. The results are also discussed in terms of their implications for theories of L2 phonetics.

Domain-initial articulatory strengthening in four languages

This paper is about one way in which prosody affects individual speech segments, with segmental phonetics showing a perhaps surprising sensitivity to higher-level linguistic structure. By prosody we mean the phrasal and tonal organisation of speech. We will show that phonetic properties of individual segments depend on their prosodic position, or position in prosodic structure.

Preboundary lengthening and boundary-related spatial expansion in Korean.

No abstract is provided for this article.

Prosodic strengthening of German fricatives in duration and assimilatory devoicing

This study addressed prosodic effects on the duration of and amount of glottal vibration in German word-initial fricatives /f, v, z/ in assimilatory and non-assimilatory devoicing contexts. Fricatives following /ə/ (non-assimilation context) were longer and were produced with less glottal vibration after higher prosodic boundaries, reflecting domain-initial prosodic strengthening. After /t/ (assimilation context), lenis fricatives (/v, z/) were produced with less glottal vibration than after /ə/, due to assimilatory devoicing. This devoicing was especially strong across lower prosodic boundaries, showing the influence of prosodic structure on sandhi processes. Reduction in glottal vibration made lenis fricatives more fortis-like (/f, s/). Importantly, fricative duration, another major cue to the fortis-lenis distinction, was affected by initial lengthening, but not by assimilation. Hence, at smaller boundaries, fricatives were more devoiced (more fortis-like), but also shorter (more lenis-like). As a consequence, the fortis and lenis fricatives remained acoustically distinct in all prosodic and segmental contexts. Overall, /z/ was devoiced to a greater extent than /v/. Since /z/ does not have a fortis counterpart in word-initial position, these findings suggest that phonotactic restrictions constrain phonetic processes. The present study illuminates a complex interaction of prosody, sandhi processes, and phonotactics, yielding systematic phonetic cues to prosodic structure and phonological distinctions.

Domain-initial strengthening in four languages

Prosodic strengthening in the articulation of English /æ/

The current study investigates how prosodic strengthening induced by boundary and accent influences the articulation of English low front vowel /ae/ in add, had, and pad. Using Electromagnetic Articulograph (EMA), lip and jaw opening maxima, and tongue dorsum maxima in the horizontal (x) and vertical (y) dimensions were measured during the vocalic production. Boundary-induced strengthening was found in the tongue height (TD-y) dimension in all three words: /ae/ was lower domain-initially than -medially. In other measures, the boundary effect was conditioned by accent and the location of /ae/ within words. Domaininitial strengthening was found with the jaw opening maxima, with larger opening in a higher prosodic position, but it was only when the target words were unaccented. Also, the vowel in add tended to get fronted in a domain-initial position, but the same tendency was not observed in had and pad, suggesting the possibility that initial strengthening effect is conditioned by ‘phonological’ distance from the boundary edge. (had is phonologically similar to pad in that /h/ and /p/ occupy a phonological onset position.) Accent-induced strengthening was robust in all four articulatory measures. Results show that an accent-independent boundary effect is observed on vowels even in a language with lexical stress, and that the articulatory planning for the boundary-induced strengthening on vowels interacts with accent-induced strengthening.

An Acoustic Stuty of the Stress and Intonational System in Lakhota

This paper reports a preliminary result of an acoustic study on the stress and intonational system in Lakhota, a native American language. It investigates how the stress and intonation in Lakhota are phonetically manifested; and how the stress interacts with other prosodic factors. The results preliminarily obtained from one native Lakhota speaker suggest that the primary cue of the stress is relatively high F0 which is often accompanied by higher intensity (for the vowel) and longer VOT (for aspirated stops). The results also indicate that stress is not reliably marked by duration. The stress system, however, interacts with the intonational pattern, such that, for example, intonational peak falls on the stressed syllable with a general pattern of L+H* and that it interacts with the boundary tone L%, resulting in mid tone utterance-finally. This paper can be viewed largely as a qualitative study on an understudied native American language, Lakhota and as forming a basis for further development of its stress and intonation system whose acoustic properties of its prosodic system have not been investigated before.

Articulatory and acoustic studies on domain-initial strengthening in Korean

This study examines the effect of prosodic position on segmental properties of Korean consonants /n, t, th, t*/ along the articulatory parameters peak linguopalatal contact and stop seal duration, and several acoustic parameters. These parameters were compared in initial position in different domains of the Korean prosodic hierarchy. The first result is that consonants initial in higher prosodic domains are articulatorily stronger than those in lower domains, in the sense of having more linguopalatal contact. Second, there is a strong correlation between linguopalatal contact and duration (both articulatory and acoustic), suggesting that “strengthening” and “lengthening” is a single effect in Korean. We interpret this relation as one of undershoot: in weaker positions, consonants are shorter and undershoot contact targets. The different consonant manners of Korean can be characterized as varying in both duration and contact in this way. Third, there is another, less consistent, kind of lengthening and strengthening specific to Korean, namely that tense and aspirated consonant oral articulations can be longer and stronger word-medially than word-initially. Fourth, the acoustic properties VOT, total voiceless interval, %voicing during closure, nasal energy minimum, and to a lesser extent stop burst energy and voicing into closure, were found to vary with prosodic position and, in some cases, to correlate with linguopalatal contact. They could thus potentially provide cues to listeners about prosodic structure.

Prosodic strengthening on the /s/-stop cluster and the phonetic implementation of an allophonic rule in English

This acoustic study investigates effects of boundary and prominence on the temporal structure of s#CV and #sCV in English, and on the phonetic implementation of the allophonic rule whereby a voiceless stop after /s/ becomes unaspirated. Results obtained with acoustic temporal measures for /sCV/ sequences showed that the segments at the source of prosodic strengthening (i.e., /s/ in #sCV for boundary marking and the nucleus vowel for prominence marking) were expanded in both absolute and relational terms, whereas other durational components distant from the source (e.g., stop closure duration in #sCV) showed temporal expansion only in the absolute measure. This suggests that speakers make an extra effort to expand the very first segment and the nucleus vowel more than the rest of the sequence in order to signal the pivotal loci of the boundary vs. the prominence information. The potentially ambiguous s#CV and #sCV sequences (e.g., ice#can vs. eye#scan) were never found to be neutralized even in the phrase-internal condition, cuing the underlying syllable structures with fine phonetic detail. Most crucially, an already short lag VOT in #sCV (due to the allophonic rule) was shortened further under prosodic strengthening, which was interpreted as enhancement of the phonetic feature {voiceless unaspirated}. It was proposed that prosodic strengthening makes crucial reference to the phonetic feature system of the language and operates on a phonetic feature, including the one derived by a language-specific allophonic rule. An alternative account was also discussed in gestural terms in the framework of Articulatory Phonology.

The Use of Domain-initial Strengthening in Segmentation of Continuous English Speech

Prosodic structure in English speech is signalled, in part, by stronger articulation of consonants at the onset of intonational phrases (IPs) than of consonants that are IP-medial. In two cross-modal priming experiments, American English listeners heard sentences and decided whether visual letter strings, presented during the sentences, were real words. We manipulated sentence type (either no IP boundary or an IP boundary in a critical two-word sequence), splicing (whether the onset of the sequence’s second word was spliced from another token of that sentence or cross-spliced from a matched sentence with or without an IP boundary), and relatedness (whether the visual target was the first word in the spoken sequence). There was a relatedness effect on target responses for sentences with no IP boundary only when they were cross-spliced, that is, where splicing provided evidence of domain-initial strengthening. Listeners thus use this evidence when segmenting continuous speech.

Influence of prosodic factors on segment articulations and acoustics in English

This study investigated effects of three prosodic factors—prosodic boundary, lexical stress, and accent—on articulatory and acoustic realizations of two CV syllables, /nE/ and /tE/. These syllables occurred at the beginning of trisyllabic English nonwords; their position in the larger phrase (prosodic boundary conditions), and whether they were lexically stressed and/or accented (prominence conditions) were varied. Articulatory measurements included linguopalatal contact (by electropalatography) for both C and V, stop consonant seal duration, and C-to-V contact difference; acoustic measurements include nasal duration and energy for /n/; VOT, burst energy and spectral center of gravity for /t/; and F1, vowel duration and vowel amplitude for /E/. We tested whether domain-initial strengthening occurs in the C and/or the V segments independently of stress or accent conditions. We found that the effects of position and of stress/accent can be distinguished in the production and the acoustics of these syllables. One domain-initial effect (greater consonant contact domain-initially) was complementary to one stress/accent effect (greater vowel opening with stress/accent); in other cases the effects overlapped (greater vowel energy and tendency to longer consonant both domain-initially and with stress/accent); in one case they conflicted (less consonant energy domain-initially, more consonant energy with stress/accent).

Use of segmental detail as a cue to prosodic structure in reference to information structure in German

Listeners often make use of suprasegmental features to compute a prosodic structure and thereby infer an information structure. In this study, we ask whether listeners also use segmental details as a cue to the prosodic structure (and thus also the information structure) of an utterance. To this end, we examined the effects of segmental variation of German auxiliary haben (‘to have’)—i.e., hyperarticulated [habən], moderately reduced [habm], and strongly reduced [ham]. Three remotely accessed online mouse-tracking experiments were carried out by adapting the lab-based experimental paradigms used in Roettger and Franke (2019). They showed effects of pitch accent on the auxiliary haben, leading to the interpretation of an affirmative answer to a preceding question, thus anticipating an upcoming referent noun to be the same as the one given in the question (i.e., the verum focus effect). Experiment 1 adapted the design Roettger and Franke (2019) to an online setting. In Experiment 2, listeners were indeed found to make use of the segmental detail of the auxiliary haben, even in the absence of f0 (pitch accent) information—i.e., the hyperarticulated (full) form showed an effect similar to the pitch accented form, albeit smaller. In Experiment 3, we confirmed that the observed segmental effects were not simply due to learning that might have taken place during the experiment. Our results thus imply that the analysis of prosodic structure, which is often assumed to occur in parallel with the segmental analysis, must integrate segmental details that help to signal the prosodic structure.

What are the letters of speech? Testing the role of phonological specification and phonetic similarity in perceptual learning

Recent studies on perceptual learning have indicated that listeners use some form of pre-lexical abstraction (an intermediate unit) between the acoustic input and lexical representations of words. Patterns of generalization of learning that can be observed with the perceptual learning paradigm have also been effectively examined for exploring the nature of these intermediate pre-lexical units. We here test whether perceptual learning generalizes to other sounds that share an underlying or a phonetic representation with the sounds based on which learning has taken place. This was achieved by exposing listeners to phonologically altered (tensified) plain (lax) stops in Korean (i.e., underlyingly plain stops are produced as tense due to a phonological process in Korean) with which listeners learned to recalibrate place of articulation in tensified plain stops. After the recalibration with tensified plain stops, Korean listeners generalized perceptual learning (1) to phonetically similar but underlyingly (phonemically) different stops (i.e., from tensified plain stops to underlyingly tense stops) and (2) to phonetically dissimilar but underlyingly (phonemically) same stops (i.e., from tensified plain stops to non-tensified ones) while generalization failed to phonetically dissimilar and underlyingly different consonants (aspirated stops and nasals) even though they share the same [place] feature. The results imply that pre-lexical units can be better understood in terms of phonetically-definable segments of granular size rather than phonological features, although perceptual learning appears to make some reference to the underlying (phonemic) representation of speech sounds based on which learning takes place.

Perceptual Recovery from Consonant-Cluster Simplification in Korean Using Language-Specific Phonological Knowledge

Two experiments examined whether perceptual recovery from Korean consonant-cluster simplification is based on language-specific phonological knowledge. In

Effects of continuing linguistic input on the use of segmentation cues

No abstract is provided for this article.

Phonetic focus-marking in Korean-speaking 7- to 8-year-olds and adults.

Prosodic strengthening on consonantal nasality and its asymmetric coarticulatory influence on vowel nasalization in CVN# and #NVC in English.

This study was supported by the National Research Foundation of Korean Grant funded by the Korean Government (NRF2013S1A2A2035410) to Taehong Cho.

WPP, No. 106: Effects of Initial Position versus Prominence in English

UCLA Working Papers in Phonetics No. 106, pp. 1-33 Effects of initial position versus prominence in English Taehong Cho Hanyang University, Korea tcho@hanyang.ac.kr Patricia Keating keating@humnet.ucla.edu Abstract This study investigates effects of three prosodic factors—prosodic boundary (Utterance-initial vs. Utterance-medial), lexical stress (primary vs. secondary) and phrasal accent (accented vs. unaccented)—on articulatory and acoustic realizations of word-initial CVs (/ne/, /te/) in trisyllabic English words. Articulatory measurements include linguopalatal contact (by electropalatography) for both C and V, and seal duration; acoustic measurements include nasal duration and energy for /n/, VOT, burst energy and spectral center of gravity for /t/, and F1, vowel duration and vowel amplitude for /e/. Several specific points emerge. First, domain-initial articulation is differentiated from stress- or accent-induced articulations in many aspects; for the most part, prominence affects vowel measures while initial position affects consonant measures. Nonetheless, the vowel is also effectively louder domain-initially, suggesting that the boundary effect is not strictly local to the initial consonant. Second, the boundary (domain-initial) effect is not seen across-the-board, but is often constrained by stress and accent factors, revealing that domain-initial strengthening is more effective when a relevant phonetic dimension does not undergo a compelling strengthening coming from stress or accent. Third, some accentual effects can be seen on secondary-stressed syllables, suggesting that accentual influences spread beyond the primary-stressed syllable. But this spread is mainly seen with consonantal measures, showing an asymmetric accentual influence between consonantal and vocalic articulations. 1. Introduction Prosodic structure has been widely recognized as an essential element of speech production, as it conveys a great deal of both structural and discourse information (Selkirk, 1995; Swerts & Geluykens, 1994; Herman, 2000). A large body of phonetic studies in the past two decades has increasingly demonstrated the importance of fine-grained phonetic detail in building up differential prosodic structures of utterances. One of the most conspicuous phonetic hallmarks of prosodic structure is domain-final lengthening (e.g. Klatt, 1975; Wightman et al., 1992; Gussenhoven & Rietveld, 1992, Edwards, Beckman & Fletcher, 1991; Cho, 2002, 2006; Byrd,