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.

In 2007 Lindblom et al. introduced a methodological tool to disentangle consonant-vowel (CV) coarticulation attributable to emphatic stress apart from the vowel expansion effects known to accompany the prosodic overlay. After empirically accounting for the altered vowel positions, they reported small but consistent increases in F2 transition onsets in emphatically produced CVs that could not be attributed to vowel context influences, and that differed across stop place. At issue is whether the findings of these authors can be replicated, but in the opposite direction, for CVs produced at fast speaking rates. A modified locus equation regression metric was similarly used to account for rate-induced vowel reduction effects in predicting frequencies of F2 transition onsets in rapid speech. Six American-English speakers produced [V1.CV2] sequences embedded in a carrier sentence, at three speaking tempos: normal, fast, and fastest. Significant differences were found between ‘predicted’ and ‘observed’ F2 onsets across stops, with alveolars and velars showing greater decreases in F2 onsets during more rapid speech than labials. The complementary findings are discussed relative to a unified view of anticipatory coarticulation in CV production across a continuum of hyperarticulated spectral expansion to hypoarticulated spectral reduction.

Previous studies investigating anticipatory coarticulation in emphatically stressed CV sequences and during fast speaking rates reported that three factors contributed to the overall extent of the documented coarticulation. These factors were: (1) vowel identity, (2) vowel space expansion (emphasis) or reduction (fast rate), and a hypothesized (3) ‘deeper’ and ‘shallower’ stop closure contact in emphatic and faster speech, respectively. The objective of the current research was to conceptually and quantitatively unify these two studies. This was accomplished by showing that the opposite changes to frequency onsets of F2 transitions due to emphatic and rapid speech systematically vary as a function of the durational changes in the stop closure interval. Specifically, the decrease in coarticulation in emphatic speech is characterized by increases in F2 onsets and longer stop closures (relative to a normal baseline); the increase in coarticulation due to rapid speech shows concomitant decreases in F2 onsets coinciding with shorter stop closure intervals. Vocal tract area function simulations corresponding to emphatic and reduced speech implicitly support ‘deeper’ and ‘shallower’ closure contacts as a third factor contributing to the overall extent of anticipatory CV coarticulation.

Gesture is part of the linguistic capital of every culture. Members learn from birth those gestures operative in their culture and community. Once learned, the use of gestures becomes so routinized that it appears as the natural and logical way to meaningfully communicate. This paper documents, illustrates, and describes some of the hand and facial gestures in use among Yoruba people of Nigeria. Accompanying the descriptions are the interpretations of the identified quotable gestures within the socio-cultural context of their usage. Further, the paper highlights the ‘face of earnest’ because of the cross-cultural miscommunication that it generates.