Scottish accents and their value to speech science

Subtle, Mysterious and Exotic:
SCOTTISH ACCENTS
AND THEIR VALUE TO SPEECH SCIENCE
Professor James M Scobbie
With very specific thanks to:
Olga Gordeeva, Eleanor Lawson, Marianne Pouplier,
Jane Stuart-Smith, Alice Turk, Alan Wrench;
all our participants in experiments, fieldwork, outreach and teaching;
QMU, Bill Hardcastle, Fiona Gibbon, Nigel Hewlett and the ultras;
Kirsty Scobbie for endless support and the idea of doing linguistics in the first place
• Spoken language as the object of investigation
requires many disciplines and methodologies
– social sciences (social and cognitive)
– humanities
– engineering and physical sciences
– physiological and neurological sciences
– clinical professions
– educational professions
• Qualitative and quantitative approaches
– Articulatory & Acoustic Phonetics
– Phonology
Speech Science
2
•
•
•
•
•
•
Accident
Insight into a defining human characteristic
It’s difficult, satisfying and exciting
It’s fun
Broad appeal but a small empirical base
Always something new to learn, invent or
discover
• Academia as a profession
• Lovely colleagues
Why do it? Why did I do it?
3
• An accent of a language is a “sound system”
– a system of abstract “phonemes”
• around 26 consonants /p t k…/ and 12 vowels /e ɛ …/
• no words have /θ/ (bath with /f/) or /x/ (loch with /k/)
– precise spatio-temporal phonetic realisations
• coordinated scores of articulatory gestures specified in
millimetres and milliseconds
• acoustic targets
• the precise character of a vowel like /u/
– a choice of which phonemes appear in which words
• stair with /e/ or /ɛ/, floor with /e/ or /o/, town with /au/ or /u/
• league with /i/ or /iː/, crisis with /ʌi/ or /aːe/, fur with…
What is Scottish English?
4
• Around 7,000 languages and all vary, all change, but
– half of these by 0.2% of world’s population
– 40% are endangered… up to one language a fortnight dies
• Many have characteristics that are rare
– Like Scottish English’s rolled /r/?
– 20% of languages have a voiced alveolar trill
• Some real exotica? (% of languages, % of sounds)
–
–
–
–
–
Short vs. Long Diphthongs (?%) (any diphth = 11%, 10%)
Ejective stops (15%, 1.6%, from Acoma to Zulu)
Pre-aspirated fricatives (0.2%, 0.2%, Ojibwa)
Pharyngealised approx (0.4%, 0.2% Kurdish, Silha)
Pharyngealised vowels (1.3%, 3%, Archi etc.)
Exotic
5
• We are going to exemplify aspects of Scottish
English in some detail
– subtleties may leave you mystified
– subtle mysteries may intrigue you ☺
• Pronunciation, variation and possible change in
word-final consonants
– /r/
– /l/
– fricatives /f θ s ʃ/ & /v ð z ʒ/
– stops /p t k/ & /b d g/
• and vowels
Mysterious, subtle
6
• Over hundreds of years it’s clear that one
phoneme can change into another or disappear
– Southern English final /r/ became a vowel
– English /kn/ lost the /k/ part
• And subtle phonetic variation and change within
shorter timescales is normal
• How do the abstract “phonological” categories
(26 consonants and 12 vowels) relate to the
fine-grained “phonetic” details?
– Two utterly distinct types of knowledge/phenomena
– Two extremes on a continuum
A little theoretical question
7
• vowels
• stops and fricatives
• /r/ and /l/ and more vowels
Structure of rest of talk
8
• We use minimal pairs to investigate vowels,
and lexical sets
–
–
–
–
–
–
heat, niece, greed
hate, grade, daze
hit, rib, dim
hut , hum, bus,
het, hem, mess
sighed, pie, rise etc., etc.
− near, ear, here
− bear, bare, fair
− fir, birth, dirt
− fur, turps, hurt
− err, verb, earth
SE has ~ 12 vowel phonemes
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• Small “voicing” effect
brute vs. brood /u/
neat vs. need /i/
wrote vs. rode /o/
great vs. grade /e/
• Big “morphological”
effect in past tense
– brood vs. brewed /u/
– need vs. kneed /i/
voicing effect
80%
Relative increase
–
–
–
–
morphological effect
60%
40%
20%
0%
-20%
i
e
ɔ
o
u
• but only for /i/ and /u/
– rode = rowed /o/
– odd = awed /ɔ/
– grade = greyed /e/
Predictable lengthening of /i/ & /u/
10
Top right – typical SE
a.
b.
c.
d.
voicing effect
80%
Shetlandic-parented
Scottish-parented
English-parented (male)
ditto (female)
Relative increase
•
morphological effect
60%
40%
20%
0%
-20%
i
a.
b.
c.
e
o
u
d.
Effect of parental background
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• Left: side (short [a] part, longer [i] part)
• Right: sighed (long [a] part, short [i] part)
5000
0
5000
0
0.663589 0
0
Time (s)
0.7352
Time (s)
Predictable short/long /ai/ types
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• But /ai/ /i/ & /u/ appear unpredictably in certain words
– not so rule-governed, especially with word-internal /ai/
– evidence that long vs. short versions of each are emerging
• /ai/ in SE can be short (e.g. ice) or long (eyes)
– vibes, bribes, Nige,
– crisis, psycho, hyphen, rifle, spider, mitre … (next slide)
• /i/ in SE can be short (e.g. eat) or long (ease)
– league, fatigue, colleague, dweeb, seige, Aristide
• /u/ in SE can be short (e.g. oose) or long (ooze)
– dude, fugue, cube, stooge, lewd, feud, tube, Froobs
• If you have to learn the distribution of long or short
duration, then there may be 3 new vowels
Emerging vowels
13
Obstr
nitrate
ibis
Pisces
Isaac
pilot
/l/
title
idle
trifle
St Ivel
final
/r/
mitre
spider
cypher
visor
Rottweiler
Nasal
Brighton
taigon
hyphen
Ivan
Simon
/ai/ length in trochees by w eak syllable type
.
% judged "long"
100%
50%
0%
obstr
l
r
n
voiceless
stops
voiced
voiceless
voiced
fricatives
sonorants
postvocalic context
Context-specific /ai/ in trochees
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• The system of abstract categories is complex
– vowel quality is dependent on following consonant
(trifle vs. rival) or structure (side vs. sighed)
– and even non-adjacent consonants (trifle vs.
hyphen), an exotic aspect of SE
• There may be 3 new vowels, if and when vowel
quality breaks free of those environments
• We have investigated the categories through
intuition and comparison (minimal pairs: hut vs.
hat, fur vs. fir), and measurement of acoustic
representations using duration and frequency
Summary so far
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Consonant
phonemes
Labial
Lingual
td ʧʤ
Glottal
Stops
pb
Fricatives
fv
θð sz
Nasals
m
n
ŋ
Approx
w
r l
j
ʃʒ
kg
(ʍ x)
There are ~26 C phonemes in SE
h
16
• place (pre-aspirated /s/) vs. plays (devoiced /z/)
Preaspirated fricatives
17
• Ejective stops are pretty common, but there are
big idiosyncratic differences as well as social
ones
realisations of /t/
70%
60%
% of tokens
50%
40%
glottal
30%
ejective
20%
10%
0%
MCF
MCM
WCF
WCM
group
Ejective stops
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• New or previously under-reported phonetic
variants of stops and fricatives may be quite
common in final position
– ejective variants of “voiceless” stops /ptk/
– pre-aspirated variants of “voiceless” fricatives /fθsʃ/
• This may be a phonetic change to help maintain
the phonemic status quo but it is not clear it is
predicted by theories of how sounds
“dissociate” in final position for stops
Summary: stops and fricatives
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• It has been observed that final /r/ and final /l/
are weakening and becoming more vowel-like
– Acoustic analysis
– Articulatory analysis with Ultrasound Tongue
Imaging
• If and when /r/ and /l/ are “lost” from final
position in SE, this will have been because they
have “turned into” vowels (cf. RP car)
– the number of vowels will increase as /r/ is lost
– but phonological merger is also likely
• Approximately, but not exactly, a zero-sum
game
Final /r/ and /l/ and the vowels
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“the world’s
longest tongue”!
Annika Irmler
from Germany
aged 14
… but this is just
the tongue tip
• most of the
tongue is on
the inside
• it changes
shape
and
location
but not
volume
Vocal tract
22
What ultrasound lets you see
• The surface of the
tongue
• In real time
• During speech
• Safe
23
• From qualitative “transcription” to quantitative
laboratory-based studies with stabilisation
UTI: Ultrasound Tongue Imaging
24
Future: corrected high speed data
25
• Since the 1970s coda /r/-“loss” has been reported in
working class speech
• Stuart-Smith (2003) in a Glasgow corpus including 1415 year old children showed that WC girls have no
overtly rhotic consonant for coda /r/ in approximately
90% of cases, boys in about 80%
– Middle class children and older adults are rhotic, so the
stratified derhoticisation is indicative of change in progress.
– /r/ seems to be turning into a vowel right now
– Strong impression of pharyngealisation offglide on vowels
with monophthongal pharyngealisation on low back ones
Losing /r/ in Scotland
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F3
F2
F3
F2
Derhoticised ear (above)
car (below)
Rhotic ear (above)
car (below)
F3
F2
Word-final derhoticisation in ECB08
F3
F2
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• /r/ follows most vowels as a consonant in its
own right in the phonology
• We will look at the 9 monophthongs
• A typical Edinburgh rhotic speaker
– lots of ejectives
– loss of the distinction between birth vs. berth
– loss of the vowel, not the /r/, in fir, fur, err?
– /u/ is fronted and lowered, especially before /r/
Typically rhotic SE
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• Losses or potential future losses
– A phonemic distinction before /r/ for the vowels /ı/
and /ɛr/
• Earth, verb, berth, (err) = third, word, surf, birth, fur
• A gain of a vowel – “vocalisation” of /r/
– A new vowel /ɚ/ (or /r/?) in firm, worm, perm
i
ʉ
o
iɹ
ʉɹ
oɹ
e
ı
ɔ
eɹ
ɚ
ɔɹ
ɛ
a
ʌ
Rhotic Ed. speaker
ɑɹ
29
• /r/ may not be completely absent but is
– variable
– very weak acoustically (little F3 lowering)
– preceded by an audible transition
– pharyngeal sounding
– More absent-sounding after low back vowels
• Some minimal pairs are very hard to distinguish
Typical subtle derhoticisation
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• Losses or potential future losses
– the sound of /r/ at ends of words, especially rolled ones
– a phonemic distinction or two, maybe
• thud/third, hut/hurt, bud/bird, thumb/firm, bust/burst
• wad/ward, cod/cord, bomb/ Fawkes/forks, Waugh/war,
• Gains in the number of vowels
– high and front vowels giving rise to diphthongs
– a new contrast of pure vowel qualities giving rise to /ɑː/
• hat /a/ & hut /ʌ/ vs. heart /ɑː/
i
ʉ
o
iə
e
ı
ɔ
eə
ɛ
a
ʌ
ɛˤ
ʉə
oʌ
ɔˤ
ɑː
Subtle derhoticising speaker
¡
(ʕ)
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300
o
i
e
ı
F1 (Hz)
Dimension 1
ɪ
u
ɛ ɚ
ɔ
ɛ
ʌ
a
1300
3300
F2 (Hz)
Dimension 2
Edinburgh south-side
800
32
300
o
i
e
ɛ ı
F1 (Hz)
Dimension 1
ɛ
ɪ
ʌ
ʌ
a
1300
3300
West Lothian
F2 (Hz)
Dimension 2
ɔ
u
ɑ
800
33
• Good separation, /u/ is fronted and lowered,
Articulation of Ed. vowels
34
• /ı/ is appreciably lower, as expected
Articulation of vowels
35
• Tipup (LM17 onset) or tipdown (LM15 onset)
Sample ultrasound images of /r/
36
Tongue blade
raising
[he]
[ɹ]
Tongue root
retraction
[ɹ]
[he]
[ə]
Waterfall time sequence: hair
37
Pre-pausal /r/ may have late (covert?) tip
•
Low vowels sound derhoticised, acoustically
lack F2/F3 approximation, and are near-monophthongs.
•
Articulatorily a clear rhotic gesture was retained
car
38
Let’s try some movies
39
– Red = /¡/ mull (cons) & bulb (vocalised)
– Blue = /ı/ film (cons) & pill (vocalised)
• Pharyngealised (cons) vs. velarised (vocalised)
UTI of laterals
40
• the vowel space revisited
Articulation of vowels
41
• Pharyngealisation and velarisation is more
extreme in /l/ than in back vowels
/l/ compared to /ɔ/ and /o/
42
• Vocalisation of /r/, /l/ and the vowel system
/ı/
/ʌ/
/a/ /ɑ/
V
hip
hum,hut
hat
R
(firm)
fur,hurt
far,heart
L
pill,film Mull,bulb,cult
pal
• Clear difference between /r/ and /l/ in open and
closed syllables
• Open syllable /ʌr/ (fur/fir ) and /ar/ are the most
likely to lose /r/, then other /ʌ/
Derhoticising speaker
43
• /ai/, /i/ and /u/ might be splitting: long vs. short
• /l/ is vocalising but is still different to /o/
• /r/ derhoticisation in West Lothian
– acoustic targets are /r/-less
– articulatorily, the tip of the tongue gesture may
merely be delayed, so /r/ is not lost, not yet
– There may be a new long vowel /ɑ/ (far) and short
/ʌ/ may able to appear in open syllables (fur)
• In rhotic Edinburgh speakers
– the tip gesture may be early, making /r/ sound like a
vowel (in fur, fir, err)
– preaspiration and ejectives are commonplace
Summary: variation and change?
44
• Mass observation
• Detailed quantitative laboratory-based research
– multiple channels
• Applications
– speech technology
– speech and language therapy
– second language learning
• Distinct languages and traditional dialects are
dying out, but accent variation is vibrant and
demands closer theoretical attention
The future
45
• Accents change
– subtle differences in phonetic targets may acquire
social distributions
• The system largely stays the same in real time
– a language maintains its lexical items and contrasts
– losses in one area lead to gains elsewhere
• Articulatory mechanisms underlying natural
speech have rarely been observed before, and
new technologies are providing a new point of
view
– inside in the mouths, and minds, of speakers
Conclusions
46