Download Suprasegmentals

Connected speech processes
Coarticulation
Suprasegmentals
What is coarticulation?
What is coarticulation?
• “An event in speech production in which
adjustments of the speech production
system are made simultaneously for two
or more speech sounds” (Kent)
What is coarticulation?
• In other words, the features of speech
elements will vary depending upon the
context in which they are produced
Terms used that refer to this
general concept
• Coarticulation
• Coproduction
• Contextual variation
Kinds of coarticulation
• A speech event can be influenced by a
previous event
OR
• A speech event can be influenced by an
upcoming event
Coarticulation
• Anticipatory (right-to-left) coarticulation
– A segment’s features are influenced by
upcoming segment
S1 S2
Coarticulation
• Carryover (left-to-right) coarticulation
– A segment’s features are influenced by a
previous segment
S1 S2
Examples of anticipatory coarticulation
• Lip protrusion has been observed three (or
more) consonants in advance of a
rounded vowel
• e.g. /stu/ (“stew”) will exhibit lip rounding
through the /s/ and /t/
An (in)famous coarticulation study
Anticipatory coarticulation: Some
implications from study of lip rounding
by
Fredericka Bell-Berti & Katherine Harris
Haskins Laboratory
New Haven CT
Published in JASA Vol 65(3) 1979
Examples of anticipatory coarticulation
• Velopharyngeal opening can occur two
vowels in advance of a nasal consonant
• e.g. /an/ will exhibit V-P opening during the
/a/
Examples of anticipatory coarticulation
• Jaw opening for an open vowel may be
observed two consonants in advance of
the vowel
Examples of carryover coarticulation
• Velopharyngeal opening can continue into
a vowel following a nasal consonant
• e.g. /nat/ will exhibit V-P opening during
the /a/
Why is there coarticulation?
• Articulators cannot make quantum leaps
from one static position to another
Carryover coarticulation
A possible reason?
• Articulator are ‘sluggish’ and it takes time
to move on to the next sound
Anticipatory coarticulation
A possible reason?
• Articulator are ‘sluggish’ and it takes time
to move on to the next sound
Connected speech processes
Coarticulation
Suprasegmentals
Suprasegmentals
• Intonation
• Stress
• Duration
Intonation
• Manner in which Fo is varied to mark
linguistic aspects of speech
• Fo/pitch contour
• Rise-fall pattern typical for declarative
sentences
• Start-frequency - variable
• End-frequency - stable
Sound pressure waveform
start Fo
end Fo
Fo contour
Intonation
• End-frequency may be related to the
physiology of phonation
• Completing a speech breath – Psg is
lower ~ lower Fo
But, this doesn’t have to be the
case…
Intonation
• Questions are marked by a rising Fo
contour
• Can override patterns for linguistic
purposes
Stress
• Not the kind of stress you get around
exam time
• Stress is applied to parts of speech
• For example,
– Lexical stress
– Emphatic stress
Stress
• Stress typically marked by
– Higher Fo
– Higher intensity
– Longer duration
– Vowels will be more clearly articulated than
unstressed
– Perception of stress will result from some
combination of these acoustic features
Duration
• The length of speech sounds
• Why are sounds as long as they are?
– Physical requirements of their production
– Phonetic distinction (i.e. vowel length)
– Context in which they are produced
– Overall rate of speech