Week 3: Features. 2. Phonological features are part of our mental representation of sounds

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1 Linguistics 107 Winter Representations in phonology Week 3: Features 2. Phonological features are part of our mental representation of sounds These representations are rather abstract in that they embody certain, but not all, properties of linguistic sounds 3. Features are one of the core building blocks of linguistic representations; segments (sounds) consist of a series of features, a feature matrix e.g. kœb = -syllabic +syllabic -syllabic -sonorant +sonorant -sonorant -voice +voice +voice +stop -stop +stop -nasal -nasal -nasal +velar +low +labial -back The IPA symbols are convenient abbreviations for the bundle of features 4. The features do not encode small phonetic details which change depending on the speech rate, the person speaking, how fast someone is speaking, whether someone has a cold, etc. 5. The features play an important role in defining natural classes, as we ve seen already. A natural class shares a feature or set of features. 6. With the features, it is possible to formalize phonological rules e.g. Nasalization of vowels before nasals in English [+syllabic] [+nasal] / [+nasal] 7. This rule states that any syllabic sound becomes nasalized before another nasal sound. We thus find any sound whose feature matrix contains the feature [+syllabic] and change its nasal feature to [+nasal] before any sound with the feature [+nasal] 1

2 e.g. /kœn/ = -syllabic +syllabic -syllabic -sonorant +sonorant +sonorant -voice +voice +voice +stop -stop +stop Environment -nasal -nasal +nasal +velar +low +alveolar -back e.g. /kœn/ = -syllabic +syllabic -syllabic -sonorant +sonorant +sonorant -voice +voice +voice +stop -stop +stop -nasal +nasal +nasal +velar +low +alveolar -back Note that any sound with the feature [+syllabic] undergoes this rule. 8. Typically, phonologists use the minimal number of features possible to accurately describe the rule. 9. In the case of the nasalization rule, it is enough to say [+syllabic]; we don t need to also say [+voice], [+sonorant], [-stop], etc.; these other features are redundant, since all [+syllabic] sounds in English are also [+voice], [+sonorant], [-stop]. 10. A set of features The features we will use follow fairly closely (but not completely) those proposed by Chomsky and Halle (1968) in their work The Sound Pattern of English (SPE) 11. In phonetics, we often talk about manner classes like stops, affricates, fricatives, nasals, liquids (=l, r), glides, vowels and place classes like dental, alveolar, labiodental, retroflex, palatoalveolar, palatal, velar, uvular, etc. 12. Phonology interested in classes of sounds which pattern together in terms of rules Many of the phonetic classes of sounds pattern together in the phonology; for this reason, there is a clear phonetic basis for most phonological features However, some sounds which may seem quite different phonetically may form a natural class in terms of phonological features 2

3 e.g. Approximants, taps and trills are often assumed to have the phonological feature [+approximant], even though we know that, phonetically, they are articulated quite differently. Crucially, they tend to behave similarly in terms of rules; they thus are all [+approximant] e.g. In Indonesian, the velar nasal in /m N-/ prefix deletes before glides, liquids, or nasals, stops, affricates, fricatives devoice word-finally in many languages, in some languages, stops and affricates become aspirated word-finally, in some languages, an voicing contrasts between obstruents are only allowed before nasals, liquids, glides, vowels 13. Manner features Sonority hierarchy (more later on this) vowels glides liquids nasals fricatives stops incl. affr. [+syllabic][ -syllabic ] [ -consonantal ][ +consonantal ] [ +approximant ][ -approximant ] [ +sonorant ][ -sonorant ] [ +continuant ][ -cont ] 14. Phonological features can capture these classes of sounds that pattern together in either undergoing a rule or triggering it. e.g. the set of glides, liquids, nasals = [+sonorant, -syllabic]. e.g. the set of vowels, glides, liquids, nasals = [+sonorant] e.g. the set of stops, affricates, fricatives = [-sonorant] e.g. the set of stops, affricates = [-continuant] 15. A closer look at the individual manner features 16. [syllabic] sounds which are part of the nucleus of the syllable are [+syllabic] sounds which are in the onset and coda are [-syllabic] [Syllabic] is thus defined in terms of position in the syllable; for this reason, the same sound can be either [+syllabic] or [-syllabic] depending on the position in the syllable 3

4 This flexibility based on syllable position makes [syllabic] differ from other manner features e.g. English [n] in night and tan is [-syllabic], but in button is [+syllabic]. English [l] in light and tall is [-syllabic], but in cattle is [+syllabic] Note: Glides and vowels differ only in terms of their [syllabic] feature; vowels are [+syllabic], glides are [-syllabic]; so, a [+syllabic] glide = a vowel 17. The types of sounds which can be [+syllabic] varies depending on language, but follows an implicational hierarchy: if a certain segment can be [+syllabic] in a given language, then all other segments of greater sonority can also be [+syllabic] More sonority Less sonority Vowels/Glides Liquids (usually includes taps, trills) Nasals Fricatives Stops (including affricates) 18. Languages draw different cut-off points along this hierarchy in terms of which sounds can be [+syllabic] In Czech, only vowels and liquids may be [+syllabic]. In English, only vowels, liquids, and nasals may be [+syllabic]. In some Berber dialects, all sounds can be [+syllabic] depending of course on neighboring sounds 19. What we do not expect to find: Languages in which a lesser sonority sound can be syllabic but one of higher sonority cannot be e.g. Nasals can be syllabic but liquids cannot, fricatives can be syllabic but nasals cannot, etc. 19. The sonority hierarchy usually predicts the order of sounds in a syllable. The sonority increases from the left edge of the syllable to the nucleus and then decreases from the nucleus to the right edge. e.g. crisp [k I s p] stop liquid vowel fricative stop 4

5 20. Note, there are exceptions to this sonority sequencing principle, usually involving /s/ e.g. English streets : both /s/ at beginning and end disobey sonority sequencing principle 21. [approximant] (non-spe feature) Vowels, glides, liquids are [+approximant]; also trills, taps Nasals, fricatives, stops/affricates are [-approximant] This class is harder to define phonetically because of inclusion of trills, taps 22. [sonorant] Vowels, glides, liquids, nasals are [+sonorant] Fricatives, stops/affricates are [-sonorant] (=obstruents) 23. Phonetically, the [-sonorant] sounds have a tight enough constriction to allow substantial pressure build up in the mouth; this makes voicing difficult for the [- sonorants] for aerodynamic reasons The [+sonorant] sounds, on the other hand, do not suffer from a substantial pressure increase in the mouth during their production 24. Sonorants and obstruents have different distributions in terms of voicing Voiced obstruents rare (compared to voiceless obstruents), but voiced sonorants common 25. Other phenomena which treat sonorants and obstruents differently e.g. Japanese: a word can only have one voiced obstruent (Lyman s Law), but a word can have more than one voiced sonorant, even in words with a voiced obstruent, e.g. [o igami] is fine but not words like [godo o] 26. [delayed release] Stops = [-delayed release] Affricates = [+delayed release] 27. One way to think about [delayed release] After the stop phase, the [+delayed release] sounds do not immediately release their constriction entirely; the release is delayed since the fricative phase still involves a constriction 5

6 28. [continuant] 29.[Continuant] is sort of a tricky feature, since it can defined in two ways, each of which means a slightly different result in terms of which sounds are [+continuant] and which ones are [-continuant] 30. Traditional SPE view: [continuant] is articulatory-based: [-continuant] sounds have a closure in the oral cavity, while [+continuant] sounds do not. This means that nasal stops are [-continuant] This is right is some respects, e.g. English voiced fricatives become oral stops before nasals: [Izn`t] [Idn`t] (assimilation of [+continuant] to [-continuant] before a [- continuant] 31. But, if we define [continuant] in terms of sonority scale, nasals should be [+continuant] since it is the feature used to group nasals and fricatives together and separate from stops/affricates 32. Possible solution: Separate acoustic [continuant] and articulatory [continuant] features, which play different roles in the phonology Articulatory vs. acoustic features is a general issue in phonological theory (more later) 33. Features for vowels 34. A course classification [-back] [+back] [+high, -low]: i y È/ u [-high, -low]: e ø /ø o [-high, +low]: œ a/a Å 35. If [round] and [tense] are added, we can describe a wider ranger of vowels -back +back -round +round -round +round +tense i y È/ u -tense I Y - U +tense e ø Ø o -tense E { /ø O +tense œ tense a A Å Notes: Note that cells marked with a hyphen do not have an IPA vowel which has the relevant features. 6

7 The features used in (35) are basically those used in Sound Pattern of English 36. More on the feature [tense] 37. The feature [tense] is used to describe distinctions which are described in terms of height in Course in Phonetics (e.g. [i] vs. [I] = high vs. lower high, [e] vs. [E] mid vs. lower mid) 38. [Tense] is difficult to define precisely in phonetic terms, unlike features based on vowel height 39. However, phonologically speaking, the tense vowels have a different distribution from the lax vowels in many languages; In English, a word cannot consist of only a consonant followed by a lax vowel in an open syllable (*[se], [si], [su], [so]), whereas English has lots of words consisting of a consonant followed by a tense vowel in an open syllable (e.g. say, see, sue, sew ) In certain languages, tense vowels become lax in closed syllables 40. Also, the feature [tense] has been used to describe ATR/RTR differences in African languages) 41. But, the tense/lax distinction in English is phonetically quite different from the ATR/RTR distinction in African language 42. It is interesting to note that the tense vowels are phonetically longer than the lax vowels; thus one of the phonetic properties associated with [+tense] is additional duration 43. In fact, it has been proposed that the tense/lax distinction in English is really a long/short distinction. 44. More on central vs. back vowels 45. The features in (35) don t have a way of distinguishing between back and central vowels. 46. This is okay in languages which have only back vowels or only central vowels 47. Also, in languages in which the only central vowel is schwa, one can assume that schwa lacks any features (i.e. is neutral) 48. But there are languages with both back and central vowels where schwa is not the only central vowel; for these languages, the feature set above is inadequate 7

8 49. An expanded set of vowel features (including the feature [front]) [+front, -back] [-front, -back] [-front, +back] -round +round -round +round -round +round [+high, -low, +tense] i y È Ë u [+high, -low, -tense] I Y U [-high, -low, +tense] e P - - Ø o [-high, -low, -tense] E { T ø O [-high, +low, +tense] œ [-high, +low, -tense] (a) a - A Å Notes Many missing IPA symbols representing sounds which are not used contrastively in languages Also, phonologists often use the symbol [a] for a low central vowel, even though, technically speaking [a] is a front vowel; this is for typographic reasons 50. Some other vowel features [+stress], [-stress] Most phonologists now think of stress as a property of syllables, though, and not individual sounds [+nasal], [-nasal] Used for nasalized vowels in languages like French (phonemic) and English (allophonic) [+ATR], [-ATR] is some African languages [+long], [-long] to capture length contrast in vowels in languages like Japanese The [long] feature is not usually used nowadays; instead it is assumed that long segments are associated with two timing positions; short segments have one. Long /a /= Short /a/= X X X \ / a a 51. Place Features for consonants 52. Defined according the major articulator involved in production lips: [+labial], tongue blade and tip: [+coronal] 8

9 tongue body: [+dorsal] (tongue root: [+radical]) 53. Simplex segments with just a single articulator have only one positively specified place feature and the others are negative: e.g. bilabials are [+labial, -coronal, -dorsal, - radical], etc. 54. Complex segments like [w], [k p] have two positively specified features: [+labial], [+dorsal] 55. Glottal sounds have no positive place features 56. Evidence for place features: the case of [coronal]: Classical Arabic definite article //al/ the is realized as [/al]/ {b, f, k, x, q,, /} (=all but alveolars and palato-alveolars) [/at]/ t [/ad]/ d [/as]/ S [/as]/ s [/az]/ z [/ar]/ r [/an]/ n Complete assimilation to [+coronal] consonants but not [-coronal] consonants 58. Subdividing the coronals 59. Coronals can be subdivided according to whether the blade or the tip of the tongue is the articulator Coronals involving the blade are [+distributed] Coronals involving only the tip are [-distributed] 60. Evidence for [distributed] In Alur, coronals in root must agree with respect to [distributed] feature (Mester 1986) tat, t1at1, *tat1, *t1at 61. Coronals can also be subdivided according to how far forward they are articulated Coronals made at the alveolar ridge or farther forward are [+anterior] 9

10 Coronals made behind the alveolar ridge or farther back are [-anterior] 62. Evidence for [anterior] In Ngiyambaa, coronals in root must agree with respect to [anterior] feature (Donaldson 1980): Laminal dentals vs. Laminal palato-alveolars t4at4, t1at1, *t4at1, *t1at4 63. A summary of coronals and their features Laminal dentals = [+distributed, +anterior] Apical alveolars = [-distributed, +anterior] Retroflexes = [-distributed, -anterior] Palato-alveolars = [+distributed, -anterior] 64. Tip for remembering which sounds are distributed: When tongue blade is used, there is a lot of contact between tongue and the roof of the mouth, contact is distributed over a wide area of the roof of the mouth 65. [strident] Sounds in which air passes through a groove in the tongue and strikes the back of the teeth are [+strident]; stridents are acoustically quite noisy [+strident]: s, z, t s, d z, S, Z, t S, d Z 66. English plural suffix is sensitive to [+strident] class Plural marker is realized as [ z] after stridents: misses, roses, Ritzes, wishes, garages, witches, ridges 67. [lateral] Lateral approximants and lateral fricatives are [+lateral] 68. Subdividing the labials 69. [round] Used to define consonants with lip rounding, not just vowels, e.g. /kw/ is [+dorsal, +round], /pw/ is [+labial, +round], /tw/ is [+coronal, +round] (Note that we cannot say that /kw/ is [+dorsal, +labial], since /k p/ also occurs in some languages.) 10

11 70. [labiodental] [labiodental] is only necessary in languages in which bilabials and labiodentals contrast 71. Subdividing the dorsals 72. Dorsals can be described using the features of vowels produced with similar articulations fronted velars (i)= [+high, -low, -back] velars ( )= [+high, -low, +back] uvulars (ø)= [-high, -low, +back] pharyngeals (A)= [-high, +low, +back] 73. In support of using these vowel features for dorsals, vowels and dorsal consonants often assimilate in place English velars become fronted before front vowels Inuktitut lowers high vowels to mid vowels before uvulars Maltese Arabic lowers /i/ to [a] before pharyngeals 74. Palatals = [+coronal, +dorsal] 75. Secondary articulations: palatalization: add [+dorsal, +high, -back] e.g. k j = [+dorsal, +high, -back] k = [+dorsal, +high, +back] velarization: add [+dorsal, +high, +back] s V = [+coronal, +anterior, -distributed, +dorsal, +high, +back] s = [+coronal, +anterior, -distributed] labialization: add [+labial, +round] kw= [+dorsal, +labial, +round, +high, +back] k = [+dorsal, +high, +back] 76. Evidence for Place as a group of features Many languages assimilate nasals to the place of a following consonant /n/ [place i ]/ +consonantal place i 11

12 Or, alternatively /n/ [αplace]/ +consonantal αplace 77. Laryngeal features 78. [voice] Voiced sounds are [+voice]; voiceless sounds are [-voice] 79. [spread glottis] [h] and aspirated sounds are [+spread glottis]; others sounds are [-spread glottis] Usually [+spread glottis] sounds are voiceless, but there are some voiced sounds which are also [+spread glottis], e.g. [bó] 80. [constricted glottis] Glottal stop, glottalized stops, ejectives and creaky segments are usually assumed to be [+constricted glottis], other sounds are [-constricted glottis] 81. Tonal features 82. The features [Hipitch] and [Lopitch] can be used to specify the 3 tones: high, mid, low High Low Mid [Hipitch] [Lopitch] For a language with more than three level tones, it is possible to use feature [High Register] Upper High Lower High Upper Low Lower Low [High Register] [Lopitch] Contour tones consist of two tonal features in sequence Falling tone = [+Hipitch] followed by [-Hipitch] Rising tone = [-Hipitch] followed by [+Hipitch] 85. When to use features in writing rules 12

13 To capture a natural class either in the target of the rule or the environment. e.g. Spanish spirantization -continuant [+continuant] / [+syllabic] +voice To capture assimilation: One feature assumes the feature value of a neighboring sound or sounds e.g. Japanese high vowel devoicing +voice [-voice]/ [-voice] [-voice] +high To show that a change is minor in terms of involving a single feature e.g. L-devoicing /l/ [-voice]/ [-voice] 86. Some current issues in feature theory Feature theory is still very much up in the air and has been complicated by recent work showing that the set of features must be expanded to include a larger number of features and both articulatory and auditory features 87. Acoustic vs. Articulatory Features Most features we ve talked about so far have been articulatory with certain exceptions, e.g. one version of [continuant]. There are processes, however, which apply to natural classes defined in terms of acoustic features. Wembawemba (Hercus 1972) /i/ becomes /y/ before retroflex consonants /i/ [+round] / +coronal -anterior -distributed There is no clear articulatory reason for this change; rather the motivation is acoustic-- both retroflex consonants and rounded vowels have low third formants; the vowel is thus rounded in an acoustic type of assimilation If we want to write a natural rule for this phenomenon, we would probably want to have an acoustic feature like [low F3] or something comparable (Flemming 1995) 13

14 88. The number of features A lot of recent work in phonology suggests that an expanded set of features might be necessary to offer a maximally explanatory account of phonological phenomena. These features will probably include acoustic as well as articulatory features 89. The universality of features Most theories of features assume that all languages share the same features. However, it is also possible that children construct feature sets with exposure to the adult language. Some features might be more relevant for some languages than for others, leading to variation in the features depending on language. 14