The effect of emphatic stress on consonant vowel coarticulation

Abstract

This study assessed the acoustic coarticulatory effects of phrasal accent on [V1.CV2] sequences, when separately applied to V1 or V2, surrounding the voiced stops [b], [d], and [g]. Three adult speakers each produced 360 tokens (six V1 contexts x ten V2 contexts x three stops x two emphasis conditions). Realizing that anticipatory coarticulation of V2 onto the intervocalic C can be influenced by prosodic effects, as well as by vowel context effects, a modified locus equation regression metric was used to isolate the effect of phrasal accent on consonantal F2 onsets, independently of prosodically induced vowel expansion effects. The analyses revealed two main emphasis-dependent effects: systematic differences in F2 onset values and the expected expansion of vowel space. By accounting for the confounding variable of stress-induced vowel space expansion, a small but consistent coarticulatory effect of emphatic stress on the consonant was uncovered in lingually produced stops, but absent in labial stops. Formant calculations based on tube models indicated similarly increased F2 onsets when stressed /d/ and /g/ were simulated with deeper occlusions resulting from more forceful closure movements during phrasal accented speech.

Stressed postverbal pronominals in Catalan

“…In particular, de Jong's (1995) hypothesis is that, under prominence, the linguistically relevant features of segments are enhanced. Evidence in favor of the localized hyperarticulation of segments comes from a variety of languages (e. g. for German: Baumann et al 2007; for Italian : Calamai 2001;for English: de Jong 1995, 2004Lindblom et al 2007, among others). Our finding that /a/ and /ɔ/ are lower in condition 1, where they receive a nuclear pitch accent, is consistent with the enhancement of linguistically encoded information (the low feature of these vowels) due to higher prominence.…”

The acoustic counterpart to coarticulation resistance and aggressiveness in locus equation metrics and vowel dispersion

“…We followed a paradigm similar to Lindblom et al (2007), in which a confederate led a scripted dialogue. In the dialogue, participants produced a C 1 VC 2 sequence (both real and nonce words) in a carrier phrase where the preceding word was invariably either "free" or "grey."…”

The Effect of Speaking Rate onConsonant Vowel Coarticulation

“…The question of interest in the present study was to test the hypothesis that coarticulatory effects during reduced speech show the opposite effects to those documented during emphatic speech. We viewed reduction effects as reflecting the 'flip side' of the same coarticulatory scenario previously documented in the Lindblom et al [2007] emphasis study. Thus, we predicted an overall lowering of F2 onsets during fast speech that could not totally be attributable to the contextual shrinkage of F1/F2 vowel space.…”

“…These alterations in F1/F2 space provide an altered contextual environment that directly affects the degree of anticipatory CV coarticulation occurring at the opposite endpoint conditions. Lindblom et al [2007] explored the question: is there a stress effect on CV coarticulation apart from the stress-induced shifts in relative vowel positions in F1/F2 space? Using a modified locus equation (LE) regression metric, they first reported lower LE slopes during emphatically produced CV sequences relative to nonstressed CV productions.…”