Cho, T. (2005). Prosodic strengthening and gestural enhancement: Evidence from acoustic and articulatory realizations of /a, i/ in English. Journal of the Acoustic Society of America, 117(6), 3867–3878.
Presentation: Sarah
Summary: Shelly
Previous studies have shown that vowels at strong prosodic positions, such as accented, domain-final, and domain-initial positions, will be prosodically enhanced. According to previous literatures, prosodic strengthening is usually accounted for by two hypotheses. One is the Sonority Expansion Hypothesis, which suggested that enhancement will strengthen the segment’s intrinsic sonority, and be reflected in increased lip/jaw opening and tongue lowering. The other is the hyperarticulation hypothesis, which predicts that contrastive features of place of articulation will be enhanced, so tongue position should be higher if the sound contains [+high], such as /i/. The above two hypotheses are in conflict with their descriptions of tongue movement, as the former predicts tongue lowering in all cases, while the latter predicts tongue raising for cases containing [+high]. In order to see which of the above is closer to reality, an experiment was conducted. Two vowels were examined, one was /a/, a [+low] vowel, and the other was /i/, a [+high] vowel. They were embedded in carrier sentences with the forms of bV1 # bV2, where V1 was at the domain-final position and V2 at the domain-initial. Six trained speakers were recruited to utter stimuli with different boundary strengths (intonational phrase boundary, intermediate phrase boundary, and word boundary), and different accentuations (ACC#ACC, ACC#UNACC, UNACC#ACC, UNACC#UNACC). Measurement of articulation was taken through seven transducer coils attached to the nose (as a reference point), the upper gumline, the incisor, and the tongue. Results of the present study showed that for /a/, lip opening is the most obvious characteristic under enhancement, but the ones at accented positions were accompanied by jaw opening, while the ones at boundary positions were not. Nevertheless, both characteristics indicated increasing sonority. As for vowel /i/, enhancement of vowel frontedness was shown at accented positions, while at boundary positions, enhancement was shown in vowel height. Though tongue movements for /i/ at both positions indicated decreasing sonority, lip opening was still found for enhanced /i/, which suggested that sonority expansion was still an intended effect. Results of the present study indicated that prosodic strengthening is not simply a phonetic event of sonority expansion or featural enhancement; it involves integration of more aspects of linguistic prominence, and this is why we see both sonority expansion (syntagmatic enhancement) and featural enhancement (paradigmatic/phonetic enhancement) taking place on one vowel.
Presentation: Sarah
Summary: Shelly
Previous studies have shown that vowels at strong prosodic positions, such as accented, domain-final, and domain-initial positions, will be prosodically enhanced. According to previous literatures, prosodic strengthening is usually accounted for by two hypotheses. One is the Sonority Expansion Hypothesis, which suggested that enhancement will strengthen the segment’s intrinsic sonority, and be reflected in increased lip/jaw opening and tongue lowering. The other is the hyperarticulation hypothesis, which predicts that contrastive features of place of articulation will be enhanced, so tongue position should be higher if the sound contains [+high], such as /i/. The above two hypotheses are in conflict with their descriptions of tongue movement, as the former predicts tongue lowering in all cases, while the latter predicts tongue raising for cases containing [+high]. In order to see which of the above is closer to reality, an experiment was conducted. Two vowels were examined, one was /a/, a [+low] vowel, and the other was /i/, a [+high] vowel. They were embedded in carrier sentences with the forms of bV1 # bV2, where V1 was at the domain-final position and V2 at the domain-initial. Six trained speakers were recruited to utter stimuli with different boundary strengths (intonational phrase boundary, intermediate phrase boundary, and word boundary), and different accentuations (ACC#ACC, ACC#UNACC, UNACC#ACC, UNACC#UNACC). Measurement of articulation was taken through seven transducer coils attached to the nose (as a reference point), the upper gumline, the incisor, and the tongue. Results of the present study showed that for /a/, lip opening is the most obvious characteristic under enhancement, but the ones at accented positions were accompanied by jaw opening, while the ones at boundary positions were not. Nevertheless, both characteristics indicated increasing sonority. As for vowel /i/, enhancement of vowel frontedness was shown at accented positions, while at boundary positions, enhancement was shown in vowel height. Though tongue movements for /i/ at both positions indicated decreasing sonority, lip opening was still found for enhanced /i/, which suggested that sonority expansion was still an intended effect. Results of the present study indicated that prosodic strengthening is not simply a phonetic event of sonority expansion or featural enhancement; it involves integration of more aspects of linguistic prominence, and this is why we see both sonority expansion (syntagmatic enhancement) and featural enhancement (paradigmatic/phonetic enhancement) taking place on one vowel.
