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Version Okt. 2007. Speech Science. W. Barry I nstitut für P honetik, U niversität des S aarlandes IPUS. Term Programme 1. Wk 1 : • What is Speech Science - scientific goals? Übung 1 Wk 2 : • Capturing and representing Speech Übung 2
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Version Okt. 2007 Speech Science W. Barry Institut für Phonetik, Universität des Saarlandes IPUS
Term Programme 1 Wk 1 : • What is Speech Science - scientific goals?Übung 1 Wk 2 : • Capturing and representing Speech Übung 2 Wk 3 : • Speech production I – Breathing Übung 3 Wk 4 : • Speech production II – Speech organs and articulation; Übung 4 Wk 5 : • Speech production III – Speech motor control 1;Übung 5 Wk 6 : • Speech production IV – Speech motor control 2; Übung 6 Wk 7 : • Acoustic structure of speech I – Source-Filter Übung 7
Term Programme 2 Wk 8 : • Acoustic structure of speech II – Vowels Übung 8 Wk 9 : • Acoustic structure of speech III – Consonants Übung 9 Wk 10: • Variable acoustics – constant perception Übung 10 Wk 11: • What do we perceive? Sounds/syllables/words? Übung 11 Wk 12: • What happens in fluent speech? – Articulation and acoustics; Übung12 Wk 13: • What do we produce when we speak? Sounds/syllables/words?; (distribute trial exam)Übung 13: Discussion of trial exam
Term Programme 3 Wk 14: • Discussion of practice exam Wk 15: • Final exam Coursebooks: R. D. Kent (1997). The Speech Sciences. San Diego/London: Singular Publishing Group, Inc. G.J. Borden, K.S. Harris & L.J. Raphael (1994). Speech Science Primer.Physiology, Acoustics and Perception of Speech. (3rd edition). Baltimore: Williams & Wilkins. B. Pompino-Marschall (2003). Einführung in die Phonetik. (2nd edition) Berlin/New York: Walter de Gruyter H. Reetz (1999). Artikulatorische und akustische Phonetik. Wissen-schaftlicher Verlag Trier (WVT).
What is Speech Science? Topics • Scientific goals • Areas of Speech Science ------------------- • "Homework": a) Kent, Chap. 1, pp. 1-20 (K) b) Borden, Harris & Raphael, Chap. 2, pp.14-23 (BHR) Deutsch: c) Pompino-Marschall, Teil I, S. 1-10; Teil II, S. 13-16 (P-M)
Scientific goals • Science: Seeks to explain the “Hows?” of the world • What are the “Hows?” of speech? • For any question “How?” there has to be a “What?” • So … what is speech? The systematic movement of our articulators? The sound patterns we perceive? The sound waves that travel from speaker to hearer? Anything else?
What is speech? • All of the things mentioned ……. but more! • We really need a “communication framework” for speech to actually take place • The articulatory movements The acoustic pressure patterns The sound patterns that we perceive HAVE TO BE RELATED TO A MESSAGE • ……… so what do we mean by “message”?
The “message” of speech? • ….. is the information the speaker conveys to the listener Which is? • Mostly, the semantic content of the utterance (though this can be metaphoric or otherwise indirect) • Also, the speaker’s attitude to the content ….. and to the person(s) being talked to • But speech also reflects things about the speaker (indexical information: sex, age, health, mood ……) • So the relationship between message and sound patterns is much more than how /i a u/ and /p t k/ are produced.
Speech as a meta-message? • Our definition of “message” can be problematical for speech research: •Speech research is often associated with unnatural utterances …(something our definition rejects as “genuine speech”?) Words set in carrier sentences Word lists containing target sounds Repeated phrases……. etc. However….. • Within the framework of the research question they DO conveyinformation to the listener (= to the investigator) …. As a meta-message = a message about the linguistic form So, within a particular theoretical question it can be valid material. • But such speech can never be considered “natural speech”
So, do we now know WHAT speech is? • A message encoded in language and expressed phonetically (i.e. through the medium of sound) ….. • ….. which means that a speaker is active, an acoustic signal is produced….. • ….. and it is assumed that the speaker is talking to someone. I.e., a hearer receives and processes the signal (decodes the message) This “speech chain” defines the broad area within which Speech Science asks its questions.
Observation domains Hearing Articulation Stimulus transform neuro- muscul. process neural processes neural processes CNS CNS Acoustics system Measure-ment Speech signal Speech signal timeas a function of Observation domains within the speech chain (adapted from P-M. p.14) Speech Chain
Speech Chain II From Denes & Pinson, 1993, p. 5
Observation domains I • Neural processes (production and perception) – increasingly of interest (psychology & medicine) EEG (Electroencephalography) and MEG (Magnetoencephalography) MRI (Magnetic Resonance Imaging) • Global information about neural activity: EEG and MEG provide high temporal resolution of activity in small areas of the brain. MRI shows activity in all areas of the brain but with low temporal resolution. • Nothing is clear from one observation (noisy signals). Patterns emerge from the average of many repetitions.
Observation domains II • Neuro-muscular processes (production) EMG (Electromyography)
Nasal cavity Hard palate Soft palate Pharynx Tongue Epiglottis Jaw Larynx Trachea Observation domains III • Articulation (Production) – Traditional observation domain in Phonetics.
Observation domains IV • Acoustic Signal – Increasingly central to speech research from 1945 onwards. • It has a central positionbetween speaker and hearer; it is the productof articulation and the input to the perception process. • Different representationsgive us information about the distribution ofacoustic energy in timeor in frequency. b) a)
Observation domains V • Auditory system (the physiological and neurological foundation of perception) Inner ear Outer ear Middle ear Semi-circular canals balance nerve auditory nerve StapesIncus Cochlear Ear canal Scala vestibuli Scala tympani Eardrum &Malleus Endolymphduct Ovalwindow Roundwindow The peripheral auditory system (ear)
Observation domains VI • Stimulus transformation (psycho-acoustics, psycho-phonetics, speech perception) • What are the acoustic properties that keep vowels and consonants, monophthongs and diphthongs, stops and fricatives, voiced and voiceless consonants apart? • The “same sound” is acoustically different when it is produced by different speakers – very different if the speakers are men vs. women vs. children. Why do they sound the same? • The “same sound” is acoustically different when it is produced in different contexts.
Summing up…… • Different observation domains give us different perspectives on what people do to communicate. • Examining the phonetic events in relation to the message gives us: a) a lot of knowledge about the structure of speech b) insight into how the properties of speech affect the message • This serves many purpose: -The formulation of theories of speech (production and perception) -The development of pronunciation-teaching methods and therapies for the speech impaired -Applications in speech and language technology