What is language? The side of sound: Phonetics and phonology and the beginning of morphology

1. What is language?The side of sound: Phonetics and phonologyand the beginning of morphology

2. Linguistics • The study of language may treat a language as a self-contained system; or it may treat it as an object that varies over space, time, and social class. • We will consider only the first (and ignore diachronic linguistics and sociolinguistics).

3. Another distinction to bear in mind Language • We can study the way in which language organizes thought and expresses statements about (perceived) reality; or, • We can study the internal structure of language systems. I'll focus on the second. We will aim to determine the distribution of items in particular languages; and to establish any universal principles that can be extracted from those to simplify the entire process. Perceived reality

4. Bear in mind... English …that English is an outlier among languages... (This is really because almost all of the volume of a hypersphere becomes arbitrarily close to the skin, as the dimensionality increases) Language

5. We humans manage to analyze an extremely complex acoustic signal and translate it into an internal representation linked to meaning with little conscious awareness of the intermediate steps or the complexity of the operation.

6. Linguistics Phonetics: sound, described as an acoustic and articulatory event Phonology: the study of systems of discrete sounds Morphology: ... the internal structure of words Syntax: ...the principles governing combinations of words. Semantics:...the relationship between syntactic structures and meaning.

7. A list of false statements about speech • The speech stream can be divided into words on the basis of short pauses between words. • The speech stream can be divided into words on the basis of something acoustic. • Words can be divided into individual sounds on the basis of their acoustic properties.

8. Words can be analyzed as a sequence of phones of roughly equal length. • Words can be analyzed as a sequence of syllables of roughly equal length. • Words (syllables) have the same duration regardless of their context. • Words of two syllables are longer than words of one syllable.

9. dad 520 msec • daddy 420 msec.

10. Language is fast! • Individual sounds can go by extremely fast (40 to 200 msec) and yet be easily grasped by the native speaker. There’s nothing else that I know of that we can do anywhere near that fast that appears to be under conscious control. • Native speakers reconstruct sounds from extremely degraded sensory input: • Jeetjet? Nah, juw?

11. The word text: the k is 40 msec out of a total of 480 msec. Fast? Vowel K S t: closure + burst

12. Language is a brain function Since 19th century, we’ve known about • Broca’s area (posterior inferior frontal lob) (damage leads to nonfluent speech, lack of grammatical markers) • Wernicke’s area (left temporal lobe, auditory association area). Damage leads to aphasia with fluent speech lacking in content.

13. Thanks Colin Phillips U of Delaware web page

14. But what is language? • A system of great complexity • Much of the complexity is learned (we know that, because it is “language-specifïc”) • It still eludes our attempts to accurately model it on computers (witness continuous speech recognition products).

15. 1. Phonetics

16. 1. Phonetics • We know more about how sound is produced than how it is perceived, generally speaking. • Source-filter model: Upon exhilation, the vocal cords vibrate freely if there is little blockage or obstruction through the mouth and nose. The frequency of that vibration is the fundamental frequency (50-200hz in males, double that in females).

17. source: Kevin Russell Articulatory apparatus

18. Vowels • For vowels, the mouth/nose acts as an echo chamber, enhancing those harmonics that resonate there. • These resonances are called formants. The first 2 formants are especially important in characterizing particular vowels.

19. “Hi” /haj/ FORMANTS we were away a year ago

20. /i/ green /ae/ hat /u/ boot graphics thanks to Kevin Russell, Univ of Manitoba

21. Vowels, crudely… • To identify a vowel is to identify its location in a 2-dimensional F1-F2 space. Improvements: • … in 3-dimensional F1-F2-F3 space • …normalized by See e.g. Harvey Sussman, The Neurogenesis of Phonology Phonological processes and brain mechanisms 1988

22. Consonants • Stops: p, t, k, b, d, g • Fricatives, affricates: ch, j, sh, th... • Nasals: m, n, ng (as in sing) • Stops and fricatives create their own turbulence, and the oral shape determines what spectrum is enhanced.

23. Spectral character of sounds • Stops show rapid change of formant frequency from their position to that of the neighboring vowel; • Fricatives should wide band of noise • Vowels show 3 (major) bands of formants whose energy is an enhancement of harmonics of the fundamental frequency (1st, 2nd, 3rd formant)

24. 3 aspects of the signal The linguistic signal can be divided into three parts: • The fundamental frequency (intonation in many languages, tone in others) • The cues to the oral gestures: energy and formant structure: vowel and consonants • Temporal (rhythmic) structure Big point: Simultaneous and co-organized analysis of these aspects

25. Fundamental Frequency • Intonation languages • Tone languages -- we’ll get to them

26. Cues to oral gestures: formants, formant changes, and spread-out noise • Formants for vowels; • Long pauses inside of stops, followed by rapid formant transitions to the following vowel • Spread out regions of noise for fricatives How do we do this? -- recognizing as many as 10 consecutive “objects” per second!

27. Rhythm and timing • Japanese: based on moras. A mora is: • a CV: ka zo ku ‘family’ wa ta shi ‘I’ • the V in CVV: ko-o-ko-o ‘high school’ • N at end of syllable: o-ba-a-sa-n ‘grandmother’ • C at end of syllable: cho - t - to ‘a little’ The length of individual moras varies greatly in duration. BUT -- the length of an entire word varies linearly with the number of moras!

28. English Syllables Japanese Moras

29. Thinking about speech like vision… • Low-level feature detectors and their kin (edge detectors, orientation detectors, movement detectors: features, rhythm) • Identification of a signal as a piece of language X (this is a tall 3 dimensional object) • Identification of the object (John; the word “spinach”)

30. Laryngeal (pitch) versus oral gestures: which is “faster”? Determining pitch could mean doing a Fourier transform and looking for peaks in the 50-300 range; or it could be done by sensitivity to resonances inside the cochlea (low level dedicated hardware!) But the length of time over which a piece of tone is stretched tends to be longer than a single phoneme.

31. 2 Phonology

32. Main points • Phonology of a language imposes highly, tightly structured organization. • Languages differ greatly from one another, but there are many deep generalizations relating them. (That is, the range of possible phonologies is large; but the range is also much smaller than it might be logically.) • The main principle to bear in mind is simultaneous signals and simultaneous constraints.

33. Sounds and sound inventories • 1. The phonemic principle in languages • 2. Categorization into vowels and consonants • 3. More refined analysis along sonority hierarchy • 4. Strong universal (anthropophonic) tendencies in selection of vowel and consonant inventories • 5. Strong symmetry tendencies: which means that sounds are composed of parts...

34. 1. The phonemic principle • Humans perceive sound chunks (“phonemes”) in discrete categories; hence ability to discriminate between exemplars is extremely good at the boundary between phonemes, and poor for within-category cases.

35. Example • Difference between /b/ and /p/ is voicing, realized phonetically as Voice-Onset Time “voiced” “voiceless” Voice Onset Time: length of time between opening the mouth and the onset of vocal fold vibrations 50 msec

36. Each language has its own inventory of phonemes • English distinguishes /b/ from /v/ • Spanish does not

37. 3. Sonority hierarchy • Vowels a > i, u • Liquids: l, r • Nasals: n, m , N (ng) • Fricatives: s, f, v, z, th, …h • Affricates: ch, j • Stops: b,d,g…p,t,k SONORANTS OBSTRUENTS

38. Sonority plays a very important role in determining what sequences of sounds are permissible in a language • It’s not the case that a word is just a sequence of sounds permitted in a language. • The set of permissible sequences is much smaller than the set of imaginable sequences...

39. Syllables • Words are sequences of permissible syllables, and in general, • Syllables are waves of sonority: decreasing sonority increasing sonority peak: the vowel

40. Syllables • The most basic syllable structure: CV • Most languages put very heavy restrictions on what consonants can appear after the vowel, in the coda: S rhyme onset coda nucleus h e l p

41. English syllable b l a c k is OK, but l b a c k: l b a ck Not a permissible sonority sequence

42. b u m p is OK, but b u p m is not. b u p m

43. Tashlhiyt Berber …allows any sequence of phonemes, and divides the sequence up into waves of 2 and 3 letters based on inherent sonority t r g l+ t >> t R . g L t ‘you locked’ t r g l + a s >> t R g . l A s ‘you locked him’ i + l d i >> i l . d i ‘he pulled’ t + l d i >> t L . d i ‘she pulled’ t l w a t >> t L . w a t

44. Competition for sonority... All phonemes must be organized into syllables; an segment will ‘capture’ a less sonorous segment on its immediate left.

45. Limitations on the syllable Many languages permit no more than three items in a syllable: Consonant + Vowel + 1 thing • C V • C V V • C V C

46. They will kill (delete) to achieve that restriction…. Yokuts passive verb: Future (nit) Aorist (it) maxnit maxit (max) tannit taanit (taan) taan + nit >> tan.nit panaanit panat (panaa) panaa + it >> panat

47. 4. Functional orientation… Bjorn Lindblom (for example): • suggests that the inventory of vowels selected is done to maximize discriminability (or a more complex objective measure, such as maximize discriminability but pay a tax on complexity [difficulty] of action).

48. Again... • Basic sounds (present in babble stage, perhaps): p t k m n i e a o u • Elaborated: add one complex gesture: clicks, ejectives, impoloseives, more vowel features like nasalization, aspiration, palatalizaiton, creaky voice • Complex systems: add two or more complexities to permissible combinations

49. Strong symmetry tendencies...

50. 5. Symmetries Inventories of sounds in language are strong symmetric: which means we’re far more likely to find a system: p t k b d g m n ng than p k b d m ng