Linguistic Stress in Language
and Speech
Kenneth de Jong
Indiana University
Chapter N+1.
Suprasegmentals
• The last chapter in phonetics descriptions
• Consists of Tone, Stress, Quantity, may-be
juncture
• Or … fundamental frequency, loudness,
duration, may-be syllable stuff
• What do these have in common?
Chapter N+1.
Suprasegmentals
• Scary
• When doing basic transcriptions, we can sorta skip them -- e.g.
no tonal minimal pairs.
• … in English … (most languages have tone contrasts, most
languages have quantity contrasts)
• Tend not to fit well with a segmental model of phonetic structure.
• Vary with spoken context. Intonation is a property of the sentence;
duration varies overall by tempo; …
• Tend not to be as well understood (linguistically) as things like
‘aspiration’, ‘point of articulation’, & ‘vowel quality’
Stress
• What is it?
• Why is it?
• What does it tell us?
What stress is:
phonetic observations
• OK, we do need it in transcriptions:
‘deepened’ vs. ‘depend’
• D.B. Fry (1955, 1958, 1965): perception
–
–
–
–
F0 pattern (some complicated stuff about pitch)
Duration (longer)
Intensity (more intense)
Other stuff (vowel quality more extreme)
• Stress vs. Accent: making sense of context
– Accent: F0 pattern varies qualitatively by context,
e.g. statement vs. question
– Other stuff more attached to the word itself
What stress is:
Phonological observations
• Many languages have something similar
to English stress
– Cross-language studies, such as de Jong
& Zawaydeh (1998): Arabic is surprisingly
like English
• Various patterns appear in a number of
languages
– Keeping track of them all creates things
like metrical phonology
What stress is:
Metrical observations
• Reduced Contrast: Unstressed items can have fewer contrasts.
• Domain: Stress is expressed over a syllable.
• Alternation: Stressed and unstressed material tends to be collated.
• Spacing: Stresses tend to be distributed evenly.
• Accent Location: Stressed items often are the site for accents.
• Culminativity: Stresses may bear a one-to-one relationship with
a higher-level unit, such as a phrase.
• Weight Sensitivity: Stresses tend to fall on heavy syllables;
heavy syllables are ones with long vowels and sometimes
consonantal codas.
• Boundedness: Stress location is often fixed in relation to a
location within a word.
• Boundedness Variation: Stress locations may either be
determined by position in morpheme or by weight sensitivity.
What stress is:
Characterizing the ‘other stuff’
• Loudness vs. Clarity
• Loud people
– Brits: Sweet (1892), Jones (1960): pulmonic force ->
heard as loudness
– Americanists: Bloomfield (1933), Trager & Smith (1951)
– More sophisticated: Lehiste (1970), Beckman (1986)
• Clear people
– Brits: Walker (1781); Jones (1960): prominence =
distinctness
– Swedish research: Ohman (1967), Engstrand (1988)
– American speech: Kent & Netsell (1971); Harris, 1978)
What stress is:
Characterizing the ‘other stuff’
• Loudness vs. Clarity
– Speech production work
• Similarities
–
–
–
–
Open up vowels
Close down consonants for contrast
Make it longer
Loudness is a way of being clear
• Differences
– Care with respect to targeting
– Being clear is harder than being loud
What stress is:
Characterizing the ‘other stuff’
• de Jong (1995)
– Compare production of words with /o/ in context of coronal
consonants
– Use X-ray microbeam facility to see what’s going on inside
– Found vowels with further tongue body retraction
– Degree of retraction was not predicted by duration increases, so it
can’t be due to undershoot mechanisms
• de Jong et al (1993)
– Consonant coarticulation
• de Jong (1998)
– Looked at articulation of post-vocalic /t/ & /d/ with stress variation
– Find variation due to something like ‘degree of effort’
Illustrative Results
Tongue tip
movement patterns
for phrase:
‘Put the t__ …’.
Solid = unstressed
‘Put’,
Dashed = stressed
‘Put’
QuickTime™ and a
TIFF (LZW) decompressor
are needed to see this picture.
What stress is:
Hyperarticulation
• “Clarity”, sweet clarity
• Connected to ‘Hyperarticulation’ (Lindblom, 1990)
– Speech production happens in a sea of variability
– Some of this is due to ‘mode of production’
– Hypoarticulation = maximize production system
considerations
– Hyperarticulation = maximize likelihood the other guy will
understand you
• Hyparticulation local to the syllable (de Jong, 1995)
• More attention in production (de Jong, 1998)
What stress is:
Testing Hyperarticulation
• Lindblom: hyperarticulation = premium on getting
information in signal
• Hyperarticulation happens in corrective focus:
– “I said ‘bed’, not ‘chair’.”
• IF corrective focus => hyperarticulation & stress =>
hyperarticulation,
• THEN stress & corrective focus should have same
effect as corrective focus.
• de Jong & Zawaydeh (2000) & de Jong (2004) test
this with vowel duration and quality effects
de Jong (2004): results for
voicing X vowel duration
Voiced
Voiceless
250
Vowel Duration (ms)
• Words like
‘flowerbed
• ‘bed’ longer
than ‘bet’
• Focus makes
difference
bigger
200
150
100
unfocused
focused
de Jong (2004): results for
voicing X vowel duration
{
{
Voiced
unfocused
focused
Primary
Secondary
Vowel Duration (ms)
• Add words like
‘bed’ - primary
stress
• ‘bed’ longer than
‘flowerbed’
• Stress & focus
have similar
effect
• Stress + focus
get even larger
effect
Voiced
Voiceless
Voiceless
300
250
200
150
100
de Jong (2004): results for
voicing X vowel duration
300
250
200
unstressed
Vowel Duration (ms)
• Add words like
‘rabid’ and ‘rabbit’
• Much shorter
• No voicing
difference
• Get a tiny effect
with focus
150
100
unfocused
focused
Results, de Jong (2004)
• To Summarize
– Both stress and focus increase duration
– Both stress and focus increase duration
contrast - specified differences get bigger
– Stress and focus interact so that contrasts
get much larger in focused & stress
material
– Side note on stress shift
What stress is:
General Attentional Model
• Other work on auditory attention in time (Jones, Kidd)
• Various properties
– Attentional selectivity: some parts of a stimulus are more
readily acted upon than others
– Attentional capture: parts which change in salient ways
tend to garner selective advantages
– Attentional integration: aspects which work together to
define an event get attended to as a unit
– Temporal expectancy: events forming regular temporal
patterns will focus attention on particular up-coming times
What stress is:
General Attentional Model
• Stress = some syllables are attentionally selected
• The attentional selectivity arises from attentional capture by
acoustic events with sudden changes
• And may exhibit attentional integration where bits of speech
which cohere and are regular form units
• Attention modulation can be governed by temporal
expectancy, wherein high attention areas can come at regular
intervals
• Attention modulation characterizes both hearer and speaker
– Speakers put important stuff in high-attention areas
– Hearers look for high-attention areas
– The match between speaker and hearer is A Good Thing
What stress is:
Phonological properties
• Reduced contrast: unstressed = low
attention area = a bad place for information
• Domain: syllable onsets = places of sudden
change => attentional capture; syllables tend
to be unitary acoustic objects => attentional
integration
• Alternation: since attention is relative,
attending to one event detracts attention from
neighboring events
What stress is:
Phonological properties
• Spacing: temporal patterning, especially regular
spacing in time, tends to make high attention areas
occur at regular intervals
• Accent location: accents help direct attention to
syllables which are hyperarticulated by the speaker
• Culminativity: if stresses are attentional objects,
having one stress per meaningful unit would make a
mechanism which allows speakers to present speech
a series of meaningful tasks
…. Good so far …
What stress is:
Phonological properties
• Weight Sensitivity: so … why DO syllables with a
final consonant tend to get stressed?
• Boundedness: and why do stresses come in
particular places in the word?
• Boundedness variation: oh yeah? if there are good
places in the word for stress, why are different
languages so different with respect to WHERE?
• Actually: if stress is so functional, Mr. Stress Man,
why DO languages stress different syllables?
• Better take a good look at language differences …
Korean Case Study:
Korean Stress Rule
• Korean stress rules
– Polianov (1936): if at end of utterance, stress the first
syllable, otherwise stress the last one
– Huh (1985) & Lee (1992): stress the first syllable always
– Lee (1974, 1985, 1989): ‘Weight sensitive’ -> stress a long
vowel or an initial syllable with a coda, otherwise stress the
second syllable
– Yu (1989): ‘Weight sensitive’ -> stress the first heavy syllable
you come to, otherwise stress the last one
– Lee (1990), Kim (1998): ‘Weight sensitive’ -> stress a heavy
first syllable, otherwise stress the second syllable
– Zong (1965), Cho (1967): ‘Unbounded’ -> it’s unpredictable
so you just memorize it.
Korean Case Study:
Lim (2000)
• Lim’s Expectations
Vowel Duration (ms)
200
175
150
125
100
75
Heavy
Light
Syllable 1
Syllable 2
Korean Case Study:
Lim (2000)
• Lim’s Expectations
– Stress heavy first
syllable
Vowel Duration (ms)
200
175
150
125
100
75
Heavy
Light
Syllable 1
Syllable 2
Korean Case Study:
Lim (2000)
• Lim’s Expectations
– Stress heavy first
syllable
– Stress light second
syllable
Vowel Duration (ms)
200
175
150
125
100
75
Heavy
Light
Syllable 1
Syllable 2
Korean Case Study:
Lim (2000)
• Lim’s Results
– No systematic
differences by
position
– No effect of weight
on position
Vowel Duration (ms)
200
175
150
125
100
75
Heavy
Light
Syllable 1
Syllable 2
Korean Case Study:
Lim (2000)
• Production Results
– No systematic differences in vowel durations, except that
vowels at the end are longer
– Syllable weight makes no difference
• Compares with Balinese production studies (Barber,
1977; Herman, 1998)
– Barber is a very reliable and experienced field worker who
relied on impressionistic transcriptions
– Herman ran acoustic measurement studies
– No systematic differences in vowel durations, except that
vowels at the end are longer
– Syllable weight makes no difference
Balinese Case Study:
Herman (1998)
• Barber (1977), first:
"There is no strong word-stress in Balinese in ordinary
speech, there is only a slight variation in loudness and
energy between the syllables of a sentence.”
• Barber (1977), then (same page later
on):
"In words of more than two syllables (not counting
suffixes), the penultimate syllable is stressed unless
the vowel is e."
Balinese Case Study:
Herman (1998)
• Herman (1998), her comment:
"It is theoretically impossible to prove that some entity
does not exist. Therefore, it is impossible to prove
that word-level accentuation does not exist in
Balinese. However, if word-level accentuation in
some form did exist, one might expect to find
certain indications of it."
Korean Case Study:
Lim (2000)
• Production Results
– No systematic differences in vowel durations,
• Summary
– KOREAN DOESN’T HAVE STRESS
– Korean Intonation Tutorial
Korean Case Study:
Lim (2000)
• Point: Though a stress system might be
functional, languages work perfectly well
without them.
• One more question: so what do we hear as
stress when listening to non-stress
languages?
Korean Case Study:
Lim (2000)
• Perception Results - ask them to locate stress
– Korean listeners tend to say stress occurs in the vicinity of a pitch
peak
– Pitch rises and falls in Korean are used to mark the edges of words
• Perception Results - suggests weight sensitivity
– The presence of consonants determines where, exactly, pitch
peaks show up
– If stresses ‘grow out of’ locations for pitch peaks, then consonants
can indirectly determine where stresses get located
– This can explain weight sensitivity
– This explanation doesn’t directly use attentional selectivity to
consonants.
Why is stress?
• The functional nature of attention modulation.
It has to do with the dynamics of speaker’s
production systems and/or the dynamics of
hearer’s perception systems and their
linkage.
• The not particularly functional nature of
language history. It has to do with the (much
slower) dynamics of language groups.
What does it tell us:
• The functional nature of stress
– Plasticity in production: people are more skilled
then they are given credit for.
– Acquisition patterns: not all segmental material is
created equal.
– Fluency complexity: speech takes place in a sea
of variability.
• The not particularly functional nature of
language history.
– Cross language differences and bio-physical
explanations
– Second language acquisition
de Jong (2004): results
Primary Stressed
Secondary Stressed
Uns tressed
{
{
{
Voiced
/œ/
Voiceless
/E/
Voiced
/œ/
Voiceless
/E/
Voiced
Voiceless
Vowel Duration (ms)
300
250
200
150
100
unfocused
focused
unfocused
focused