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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