Definition:
Coarticulation is the phenomenon in which the vocal tract begins preparing for an upcoming sound while still producing the current one, or continues a previous articulation into the current sound. Rather than producing sounds as discrete, fully independent events, the articulatory gestures for phonemes overlap in time. Coarticulation is a fundamental property of natural speech and explains why the same phoneme sounds (and looks) different in different contexts — the phoneme /k/ is produced with different tongue body positions in key [ki?] (fronted, near palate) vs. caw [k??] (backed, near velum), due to anticipatory coarticulation of the following vowel.
Types of Coarticulation
Anticipatory (right-to-left) coarticulation: An articulation is begun before the sound it belongs to — the vocal tract is already moving toward an upcoming sound’s target.
- Example: In screen, the lip rounding for /i?/ is anticipated; in scream, the lip rounding begins during the /s/
Perseverative (left-to-right) coarticulation: An articulation lingers beyond its target sound into the following sound.
- Example: Nasalization from a nasal consonant often spreads to adjacent vowels (e.g., the vowel in man is nasalized because the velum begins lowering anticipatorily and remains lowered during part of the vowel)
The Degree/Distance of Coarticulation
Coarticulation can span across:
- Adjacent segments (most commonly)
- Across syllable boundaries (inter-syllabic coarticulation, especially for lip rounding and tongue dorsum position)
- Across word boundaries in connected speech
The extent of coarticulation differs by:
- Feature (lip rounding coarticulates over longer distances than tongue tip position)
- Language (languages allow varying degrees of coarticulation in their phonotactic systems)
- Speech rate (faster speech ? greater overlap ? more coarticulation)
Coarticulation and Connected Speech
Coarticulation is the physiological foundation of many connected speech phenomena:
- Assimilation is extreme coarticulation where one sound completely takes on a feature of a neighboring sound
- Vowel nasalization before nasal consonants is a form of anticipatory coarticulation
- Lip rounding spreading from a rounded vowel to preceding consonants is coarticulation
Why Coarticulation Matters for L2 Learning
L2 learners trained on citation forms experience coarticulation as “distortion” or “speed” problems when listening to natural speech. In reality, the sounds are simply overlapping:
- Learners hear the continuous blended stream, not individual discrete phonemes
- Coarticulation means the acoustic signal of a phoneme varies by context — a /d/ before /u/ sounds different from /d/ before /i/ because lip rounding from /u/ begins during /d/
- Perceptual learning involves learning to normalize for coarticulation and still identify the underlying phoneme categories correctly
Coarticulation and Phoneme Constancy
The phoneme as an abstract unit is psychologically constant even though its acoustic and articulatory realization varies continuously with context. This gap between abstract phonological form and physical signal is partly bridged by listener normalization — the cognitive process by which listeners extract the intended phoneme from a context-influenced acoustics token.
History
The term coarticulation was popularized by Öhman (1966), who demonstrated anticipatory coarticulation of vowels across consonants using X-ray data. Earlier acoustic analyses by Joos (1948) and Potter, Kopp & Green (1947) in the acoustic era set the groundwork. Motor theory of speech perception (Liberman & Mattingly, 1985) specifically argued that listeners perceive intended articulatory gestures rather than acoustic segments, partly to account for coarticulation.
Common Misconceptions
- “Coarticulation is speech error or laziness” — Coarticulation is a universal, efficient property of human speech motor control; it occurs in all speakers and all languages
- “Learners should avoid coarticulation” — Avoiding coarticulation would make speech robotic and unnatural; it is a goal of L2 fluency, not a problem to eliminate
Criticisms
- The precise extent of anticipatory coarticulation differs greatly across studies and methods; articulatory and acoustic measures do not always agree
Social Media Sentiment
Coarticulation is primarily discussed in linguistics and phonetics academic circles rather than mainstream language learning communities, but it underlies the common learner complaint “native speakers speak too fast and blend words together.” Last updated: 2026-04
Practical Application
- Explain to learners that connected speech “blending” is lawful coarticulation, not carelessness — this reframes fast speech as analyzable not mysterious
- Dictation tasks with natural-speed audio train learners to normalize for coarticulation in perception
Related Terms
See Also
Research
- Öhman, S. E. G. (1966). Coarticulation in VCV utterances: Spectrographic measurements. Journal of the Acoustical Society of America, 39(1), 151–168. — Classic experimental demonstration of anticipatory coarticulation spanning a consonant.
- Liberman, A. M., & Mattingly, I. G. (1985). The motor theory of speech perception revised. Cognition, 21(1), 1–36. — Theoretical framework in which coarticulation motivated the claim that listeners perceive articulatory gestures, not acoustic segments.
- Recasens, D. (2018). Coarticulation. In M. Aronoff & J. Rees-Miller (Eds.), The Handbook of Linguistics (2nd ed.). Blackwell. — Contemporary overview of coarticulation research and models.