@article{ChladkovaHamannWilliamsetal.2017,
  author    = {Chladkova, Katerina and Hamann, Silke and Williams, Daniel and Hellmuth, Sam},
  title     = {F2 slope as a Perceptual Cue for the Front-Back Contrast in Standard Southern British English},
  series = {Language and speech},
  volume    = {60},
  journal   = {Language and speech},
  publisher = {Sage Publ.},
  address   = {London},
  issn      = {0023-8309},
  doi       = {10.1177/0023830916650991},
  pages     = {377 -- 398},
  year      = {2017},
  abstract  = {Acoustic studies of several languages indicate that second-formant (F2) slopes in high vowels have opposing directions (independent of consonantal context): front [i.]-like vowels are produced with a rising F2 slope, whereas back [u.]-like vowels are produced with a falling F2 slope. The present study first reports acoustic measurements that confirm this pattern for the English variety of Standard Southern British English (SSBE), where /u./ has shifted from the back to the front area of the vowel space and is now realized with higher midpoint F2 values than several decades ago. Subsequently, we test whether the direction of F2 slope also serves as a reliable cue to the /i.// u./ contrast in perception. The findings show that F2 slope direction is used as a cue (additional to midpoint formant values) to distinguish /i./ from /u./by both young and older Standard Southern British English listeners: an otherwise ambiguous token is identified as /i./if it has a rising F2 slope and as /u./if it has a falling F2 slope. Furthermore, our results indicate that listeners generalize their reliance on F2 slope to other contrasts, namely /epsilon/-/./and /ae/-/./, even though F2 slope is not employed to differentiate these vowels in production. This suggests that in Standard Southern British English, a rising F2 seems to be perceptually associated with an abstract feature such as [+ front], whereas a falling F2 with an abstract feature such as [-front].},
  language  = {en}
}
@article{MayrMorrisMennenetal.2017,
  author    = {Mayr, Robert and Morris, Jonathan and Mennen, Ineke and Williams, Daniel},
  title     = {Disentangling the effects of long-term language contact and individual bilingualism: The case of monophthongs in Welsh and English},
  series = {International journal of bilingualism : cross-disciplinary, cross-linguistic studies of language behavior},
  volume    = {21},
  journal   = {International journal of bilingualism : cross-disciplinary, cross-linguistic studies of language behavior},
  publisher = {Sage Publ.},
  address   = {London},
  issn      = {1367-0069},
  doi       = {10.1177/1367006915614921},
  pages     = {245 -- 267},
  year      = {2017},
  abstract  = {Aims and objectives: This study investigates the effects of individual bilingualism and long-term language contact on monophthongal vowel productions in English and Welsh. Design: To this end, we recorded the Welsh and English vowel productions of two sets of Welsh-English bilinguals differing in home language use, as well as the English vowel productions of English monolinguals. Data and analysis: The data were analysed acoustically, with a focus on spectral and temporal properties. Comparisons were then made within each language and cross-linguistically. Findings: The results of a cross-linguistic acoustic comparison revealed a high degree of convergence in the monophthong systems of Welsh and English, but also some language-specific categories. Interestingly, at the individual level we found no effect of linguistic experience on vowel production: the two sets of bilinguals and the English monolinguals did not differ in their realisation of English vowels, and the two sets of bilinguals did not differ in their realisation of Welsh vowels. Implications: The findings demonstrate pervasive phonetic convergence in a language contact situation with a historical substrate. They also indicate that a homogeneous peer group with shared values can override the effects of individual linguistic experience.},
  language  = {en}
}