Speech Science IX How is articulation organized? Version WS

Articulatory states vs. articulatory gestures Speech sound description is based on the positions or states of the articulators not on their movements The movements from one position to another are not part of the definition of the sound structure of a language. The symbolic representation (phonetic transcription) of an utterance also suggests that the position or state of the articulators (the configuration) is the most important aspect of the sound structure. A film of speech being articulated shows that some part of the articulatory system is almost always in motion. To explain how speech works, we need a model of how the movements are controlled, a model of gesture organization.

Topics Sound categories and articulatory variability. How do we control our articulation? At what level do we control our articulation? - individual muscles? - gestures for individual sounds? - sequences of gestures for syllables? - …. for words? Reading: BHR, Chap. 5, pp ff. (Variation, Feedback, Prod.-Models) P.-M.1.4,8. pp (Steuerung)

Sound Variants A problem with definition by articulatory state is the potential “many-to-one” relationship between speech events and their causes. a) One acoustic event (speech sound) can result from different articulatory configurations (= “articulatory compensation”) b) One articulatory configuration can result from different patterns of muscular activity (= “neuromuscular compensation”)

Sound Variants (example) articulatory compensation “Standard” vs. Saarland

Sound Variants (other examples) Another well-known example of articulatory compensation is the „American /r/“ ( [  ] ) The tongue may be a) turned back (retroflex) b) bunched Lip-rounded vowels (like [ y ]) can be produced with strongly rounded, protruded lips, or with retracted tongue and neutral (or even spread) lips (with or without a lowered larynx).

Free variation vs conditioned variants Articulatory differences (requiring different commands to muscles) are not only the result of having acquired a particular variant. Sounds occur in context, and the gestures are different with every different preceding sound! This makes the relationship between one speech sound (in linguistic terms “a phoneme”) and the commands to produce it complicated.

Different movements in context Contextual differences in gestures affect every part of the articulatory patterns. Here, chin and tongue-tip interaction. tongue tip jaw- movementc ii tee ee aa t tongue tip

Context variation: Coarticulation Lip- rounding Tongue tip Example: Tüte (or tooter) When a property of one sound affects the way in which a neighbouring sound is produced, we call the effect “coarticulation”. Here lip-rounding in the initial /t/ of „Tooter“. [ t u  t  ] y 

What does this say about speech production? The motor activity involved in producing speech sounds is much more complex than the (relatively simple) phonetic- phonological categorisation of speech sounds We have to decide whether there is (or can be) any link between linguistic description and production models …. It would be unfortunate if we had to say that the two had nothing to do with each other!

But the observations also tell us …. The acoustic (  perceptual) identity of sounds seems more important than the motor equivalence When we learn to articulate, we match our own production to what we hear. The acoustic patterns from other speakers are our only models … …… nobody shows us how to move our lips, tongue, velum or larynx …….

… although … There seems to be an innate ability to imitate peoples‘ facial expressions (attributed to so-called “mirror neurons”) This has been systematically observed in very young babies, who mimic their mother‘s expressions. So there may be some visual input as well as the predominant acoustic input to the speech learning process. But only a small fraction of the articulatory activity is visible/observable.

Must our normal production processes be related to processes used in learning (i.e., perceptually based)? Theories of speech production do not always model articulation from a perceptual standpoint. Linguistic (phonological) models of sound systems are concerned with the patterns of sound produced, not with the processes that are required to produce them (BHR p. 152 f.) The IPA system is articulatorily orientated. Distinctive Feature theory (more abstract) can be articulatory or acoustic. Continuation of the discussion in Script X.

Background Article James Perkell (2000): A Theory of speech motor control and supporting data from speakers with normal hearing and with profound hearing loss. Journal of Phonetics 28, Article for copying in room 4.11 (Phonetics Secretary‘s Office)