LOT summer school Ultrasound, phonetics, phonology: Articulation for Beginners!

1. LOT summer schoolUltrasound, phonetics, phonology: Articulation for Beginners! With special thanks to collaborators Jane Stuart-Smith & Eleanor Lawson Joanne Cleland & Zoe Roxburgh Natasha Zharkova, Laura Black, Steve Cowen ReenuPunnoose, KoenSebreghts Sonja Schaeffler & Ineke Mennen ConnyHeyde Alan Wrench (aka Articulate Instruments Ltd) for AAA software and UTI hardware Various funding – thank you to ESRC, EPSRC, QMU June 2013 James M Scobbie CASL Research Centre

2. Scottish English • Derhoticisation among WC speakers • Rhotic tongue shape • Is it time for some nitty gritty stuff? • Scottish English again • Fronted /u/ • Extensions, if time • Northern Irish /u/ and diphthongs Sociophonetics / Lgvar & change

3. MRI – [o]

4. MRI – [i]

5. MRI – [y]

6. SSE /o/

7. What about real vowels?

8. Example of a UTI vowel space, un-rotated Front! Front? UTI single speakerfor comparison

9. Compare • “frontness” in F2 & “frontness” in mm • “height” in F1 & “height” in mm • What are articulatory frontness and height? Daniel Jones (1917) Experimental phonetics and its utility to the linguist. Nature 100: 96-98. • Whole tongue shape? • Constriction degree / cross-sectional area / tube diameter? • High point of the tongue surface? What about articulation?

10. Vowels • /u/ in relation to /i/ in terms of “frontness” • /u/’s similarity to /i/ in tongue shape • Easy questions are still worth asking! Some examples of something easy

11. A socially-stratified corpus (ECB08) was collected to examine social variation in post-vocalic /r/ articulation WC vs. MC teenagers • For context, each speaker produced just one (real word) token of each vowel phoneme • Labial consonants avoid lingual coarticulation • 9 monophthongal vowel phonemes • 3 diphthongs /ai/, /au/, /oi/ were not elicited • Single word citation forms, no carrier phrase • One time point was analysed – artic “target” Analysing minimal data sets

12. Video UTI, so only ~30fps • Averaging acoustics is also hard • Male and female speakers • Adolescent speakers of variable vocal tract length • No opportunity for complex normalisation What can we get out of this?

13. How front is Scottish /u/? • WC n=8, MC n=7… 1 token each hope beam boom fame awe hem hip hum Front! map

14. Formants are vocal tract resonances • A standard approach for 60 years has been to measure F1 & F2 • Low F1 = “height” & High F2 = “frontness” • We will come back to these metaphors later • Nothing is as simple as this metaphor implies, when you get down to detail • Higher formants are also important • Other factors affect these formants • But they are easy to measure, and plot well… Formants and frontness

15. Hawkins and Midgely, cf Wells, Deterding Front! SSBE for comparison

16. Calculate the F2 distance (Bark) from /i/, the vowel with the highest F2 • To /o/, /u/ and /e/ for each speaker • Repeat for a normalised set by treating the /i/-/o/ distance as 100% (corner vowel to corner vowel), which will make comparison to articulation easier • Calculate the distance (Bark) from /i/ • To /u/ and /e/ (and /o/) for each speaker • It was hard to measure F1 for /a/, so no normalisation Acoustic analysis

17. Acoustic analysis /u/ is acoustically “non-back” Relative to each speaker’s /i/ (& /o/),/u/ is Mid F2 (Hz) Mid-high F2 (Bark) 61% front (from /o/) /e/ has high F2 94% front 2 speakers have/u/ < 50% front (just) Front!

18. Acoustic analysis /u/ and /e/ are significantly “non-high” /u/ not significantly different to /e/ or /o/ in F1 In 5/14 speakers, /u/ had a higher rel F1 than /e/ Hz / Bark are almost identical at these frequencies

19. /u/ has a raised F2 • 2.6 Bark lower than /i/ • 4.1 Bark higher than /o/ • /u/ has a raised F1 • 0.6 Bark higher than /i/ • Non-distinct from the raised F1 of /e/, 0.4 Bark /u/ acoustic summary

20. We only have mid-sagittal tongue curves • Not passive articulators (vocal tract tube) • Not all the tongue surface • Not all the internal tongue tissue • Not lips (well, not for this data set) • One token per speaker (for this data set) • But unlike EMA • We are not limited to 3 or 4 anterior points • And unlike MRI • UTI is cheap, non-invasive, portable and quick • We can collect & trace 12 tokens of 5V in half a day With UTI…

21. UTI consistently shows Scottish /u/ is lower and centralised/fronted compared to other vowels Vowel space (typical WC) Front!

22. Front! Vowel space (typical MC)

23. What’s “horizontal” about a curving vocal tract? • What’s the orientation of the probe to the head? • Images can be rotated by you, looking, for qualitative understanding, if there is a fixed aspect ratio on x/y axes • Images can be rotated for quantitative analysis of “horizontal” and “vertical” by the analyst • Occlusal plane is replicable and standard and provides a reasonable horizontal for the anterior portion of the vocal tract High point of tongue

24. ECB08 didn’t collect occlusalbiteplanes… • Different shape hard palates don’t help • Two approaches to estimating “horizontal” rather than adopting the basic axes of the probe • common /o i/ tangent • Assumed occlusal ECB08 Soc-Lx sample

25. Articulatory analysis /u/ is fronter in articulatory space than acoustics 91%, 2mm 94% p<0.005 74%, 6mm 61% i-o 90.0%, 2mm Front! 99.6%, <1mm occlusal • /u/ is either more front than central, or fully front

26. Articulatory analysis /u/ is lower in articulatory space than acoustics • /u/ is not high and may be open-mid • It is lower than /e/ on either rotation of the space • /o/ is back… it’s not “lower”

27. Analysis of even single tokens with only linear normalisation on an estimated bite plane (or /i/-/o/ mean) is at least as valid as acoustic analysis using normalised F2 (F2=frontness) • In terms of variation and statistical difference • Findings • /u/ is fronted & /o/ is the peripheral corner vowel • KIT vowel is lower in WC system • /u/ is much more radically lowered than expected • Need to improve quantification / averaging / axes for measurement space SSE summary and conclusions

28. QMU Undergraduate project 2012-13 (Laura Black) looking at Northern Irish English (NIE) • /i e u ɔ/ & /au aioi/ • n=12 • Mix of real & pseudo words, randomised in 3 blocks • All open syllables with onset /h/, /m/ or /b/ • 3 speakers • About 1 week of basic analysis from a standing-start, followed by refinement (and checking) • Northern Irish-accented English .. Infamous for “confusing” and variable vowels …! Typical undergrad student project

29. What are monophthongs? • /i/, /u/, /e/, /ɔ/? • Traditional diphthongs are /ai/, /au/, /oi/ • How front is /u/? • What singletons are the best phonological candidates for the offglides in the diphthongs? • AAA demo NIE

30. NIE1 monophthongs

31. NIE1 diphthongs

32. NIE2 monophthongs

33. NIE2 diphthongs

34. NIE3 monophthongs

35. NIE3 diphthongs

36. /u/ ends higher & fronter (almost = /i/) than SSE • More diphthongal than NIE /i/ or even NIE /e/ • Rounded u i e N. Irish /u/

37. But /u/ is a phonetic diphthong…

38. /u/ is higher and fronter than ECB08 • Still ok forSSE • Still not ashigh as NIE Single speaker (SSE) Neutral space

39. 28 (of 30) TD children (group 1) incl singletons: • Minimal vowels set (poop, babe, peep, pope etc) • DEAP (50w pL subtest and 12w screen) • Coarticulatory VCV materials (asa, isietc) • Some coda /r/ words (hut, hurt, heart) • Other tasks were part of an experiment to test the “copyability” of US images on screen in • Group 1 vs. Group 3, raw vs. ULTRAX enhanced with presentation by machine and limited interaction • Group 2a vs. Group 2b raw vs. zero (acoustic only) with maximised interaction ULTRAX child corpus

40. ULTRAX (g1, 2012) TD 11, 23, 24, 31

41. Are the ULTRAX kids like the ECB08 corpus teenagers? • Yes  More /u/ (i-o plane)

42. Are ULTRAX group 2 like ULTRAX group 1? • Yes, pretty much, so far (n=15) More /u/ (i-o plane)

43. Rotation of ECB08 20° (assumed biteplane) • Similar results obtained using /i/-/o/ common tangent, which is about 45° different in orientation • Axes provided by the probe are intermediate • Close “high points” on these curves are tolerant of axes shift /i/ /e/ /o/ /u/ H -20 Quantifying /u/ frontness