Powered By Blogger

happiness

happiness
nothing special...

5 Januari 2010

Phoneme

Phoneme


In a language or dialect, a phoneme (from the Greek: φώνημα, phōnēma, "a sound uttered") is the smallest segmental unit of sound employed to form meaningful contrasts between utterances.

Thus a phoneme is a group of slightly different sounds which are all perceived to have the same function by speakers of the language or dialect in question. An example of a phoneme is the /k/ sound in the words kit and skill. (In transcription, phonemes are placed between slashes, as here.) Even though most native speakers don't notice this, in most dialects, the k sounds in each of these words are actually pronounced differently: they are different speech sounds, or phones (which, in transcription, are placed in square brackets). In our example, the /k/ in kit is aspirated, [kʰ], while the /k/ in skill is not, [k]. The reason why these different sounds are nonetheless considered to belong to the same phoneme in English is that if an English-speaker used one instead of the other, the meaning of the word would not change: saying [kʰ] in skill might sound odd, but the word would still be recognized. By contrast, some other sounds could be substituted which would cause a change in meaning, producing words like still (substituting /t/), spill (substituting /p/) and swill (substituting /w/). These other sounds (/t/, /p/ and /w/) are, in English, different phonemes. In some languages, however, [kʰ] and [k] are different phonemes, and are perceived as such by the speakers of those languages. Thus, in Icelandic, /kʰ/ is the first sound of kátur 'cheerful', while /k/ is the first sound of gátur 'riddles'.

In some languages, each letter in the spelling system represents one phoneme. However, in English spelling there is a poor match between spelling and phonemes. For example, the two letters sh represent the single phoneme /ʃ/, while the letters k and c can both represent the phoneme /k/ (as in kit and cat).

Phones that belong to the same phoneme, such as [t] and [tʰ] for English /t/, are called allophones. A common test to determine whether two phones are allophones or separate phonemes relies on finding minimal pairs: words that differ by only the phones in question. For example, the words tip and dip illustrate that [t] and [d] are separate phonemes, /t/ and /d/, in English, whereas the lack of such a contrast in Korean (/tʰata/ is pronounced [tʰada], for example) indicates that in this language they are allophones of a phoneme /t/.

Some linguists (such as Roman Jakobson, Morris Halle, and Noam Chomsky) consider phonemes to be further decomposable into features, such features being the true minimal constituents of language. Features overlap each other in time, as do suprasegmental phonemes in oral language and many phonemes in sign languages. Features could be designated as acoustic (Jakobson) or articulatory (Halle & Chomsky) in nature.

Background and related ideas

The term phonème was reportedly first used by A. Dufriche-Desgenettes in 1873, but it referred only to a sound of speech. The term phoneme as an abstraction was developed by the Polish linguist Jan Niecisław Baudouin de Courtenay and his student Mikołaj Kruszewski during 1875-1895. The term used by these two was fonema, the basic unit of what they called psychophonetics. The concept of the phoneme was then elaborated in the works of Nikolai Trubetzkoi and others of the Prague School (during the years 1926-1935), and in those of structuralists like Ferdinand de Saussure, Edward Sapir, and Leonard Bloomfield. Some structuralists wished to eliminate a cognitive or psycholinguistic function for the phoneme.

Later, it was also used in generative linguistics, most famously by Noam Chomsky and Morris Halle, and remains central to many accounts of the development of modern of phonology. As a theoretical concept or model, though, it has been supplemented and even replaced by others.

Some languages make use of tone for phonemic distinction. In this case, the tones used are called tonemes. Some languages distinguish words made up of the same phonemes (and tonemes) by using different durations of some elements, which are called chronemes. However, not all scholars working on languages with distinctive duration use this term.

The distinction between phonetic and phonemic systems gave rise of Kenneth Pike's concepts of Emic and etic description.
[edit] Notation

A transcription that only indicates the different phonemes of a language is said to be phonemic. In languages that are morphophonemic (vowels in particular)[clarification needed], pronunciations that correspond to the canonical alphabet pronunciations are called alphaphonemic. Such transcriptions are enclosed within virgules (slashes), / /; these show that each enclosed symbol is claimed to be phonemically meaningful. On the other hand, a transcription that indicates finer detail, including allophonic variation like the two English L's, is said to be phonetic, and is enclosed in square brackets, [ ].

The common notation used in linguistics employs virgules (slashes) (/ /) around the symbol that stands for the phoneme. For example, the phoneme for the initial consonant sound in the word "phoneme" would be written as /f/. In other words, the graphemes are , but this digraph represents one sound /f/. Allophones, more phonetically specific descriptions of how a given phoneme might be commonly instantiated, are often denoted in linguistics by the use of diacritical or other marks added to the phoneme symbols and then placed in square brackets ([ ]) to differentiate them from the phoneme in slant brackets (/ /). The conventions of orthography are then kept separate from both phonemes and allophones by the use of angle brackets < > to enclose the spelling.

The symbols of the International Phonetic Alphabet (IPA) and extended sets adapted to a particular language are often used by linguists to write phonemes of oral languages, with the principle being one symbol equals one categorical sound. Due to problems displaying some symbols in the early days of the Internet, systems such as X-SAMPA and Kirshenbaum were developed to represent IPA symbols in plain text. As of 2004, any modern web browser can display IPA symbols (as long as the operating system provides the appropriate fonts), and we use this system in this article.

Usually, long vowels and consonants are represented either by a length indicator or doubling of the symbol in question.
[edit] Examples

Examples of phonemes in the English language include consonant sounds like /p/ and /b/. These two are most often written consistently with one letter for each sound. However, phonemes might not be so apparent in written English, for example when they are typically represented by a group of more than one letter, called a digraph, like (pronounced /ʃ/) or (pronounced /tʃ/).

For a list of the phonemes in the English language, see IPA for English.

Two sounds which are allophones (sound variants belonging to the same phoneme) in one language may belong to separate phonemes in another language or dialect. In English, for example, /p/ has aspirated and non-aspirated allophones:aspirated as in /pɪn/, and non-aspirated as in /spɪn/. However, in many languages (e. g. Chinese), aspirated /pʰ/ is a phoneme distinct from unaspirated /p/. As another example, there is no distinction between [r] and [l] in Japanese: there is only one /r/ phoneme, though it has various allophones that can sound more like [l], [ɾ], or [r] to English speakers. The sounds [z] and [s] are distinct phonemes in English, but allophones in some variants of Spanish like 'andaluz'. The sounds [n] (as in run) and [ŋ] (as in rung) are phonemes in English, but allophones in Italian and Spanish.

An important phoneme is the chroneme, a phonemically-relevant extension of the duration of a consonant or vowel. Some languages or dialects such as Finnish or Japanese allow chronemes after both consonants and vowels. Others, like Australian English use it after only one (in the case of Australian, vowels).
[edit] Restricted phonemes

A restricted phoneme is a phoneme that can only occur in a certain environment: There are restrictions as to where it can occur. English has several restricted phonemes:

* /ŋ/, as in sing, occurs only at the end of a syllable, never at the beginning (in many other languages, such as Swahili or Thai, /ŋ/ can appear word-initially).
* /h/ occurs only before vowels and at the beginning of a syllable, never at the end (a few languages, such as Arabic, or Romanian allow /h/ syllable-finally).
* In many American dialects with the cot-caught merger, /ɔ/ occurs only before /r/, /l/, and in the diphthong /ɔɪ/.
* In non-rhotic dialects, /r/ can only occur before a vowel, never at the end of a word or before a consonant.
* Under most interpretations, /w/ and /j/ occur only before a vowel, never at the end of a syllable. However, many phonologists interpret a word like boy as either /bɔɪ/ or /bɔj/.

Biuniqueness
Wiki letter w.svg This section requires expansion.

Biuniqueness is a property of the phoneme in classic structuralist phonemics. The biuniqueness definition states that every phonetic allophone must unambiguously be assigned to one and only one phoneme. In other words, there is a many-to-one allophone-to-phoneme mapping instead of a many-to-many mapping.

The notion of biuniqueness was controversial among some pre-generative linguists and was prominently challenged by Morris Halle and Noam Chomsky in the late 1950s and early 1960s.

The unworkable aspects of the concept soon become apparent if you consider the phenomenon of flapping in North American English. In the right environment, this flapping can change either /t/ or /d/ into the allophone [ɾ] for many affected speakers. Here, one allophone is clearly assigned to two phonemes.
[edit] Neutralization, archiphoneme, underspecification
Main article: Underspecification

Phonemes that are contrastive in certain environments may not be contrastive in all environments. In the environments where they don't contrast, the contrast is said to be neutralized.

In English there are three nasal phonemes, /m, n, ŋ/, as shown by the minimal triplet,

/sʌm/ sum
/sʌn/ sun
/sʌŋ/ sung

However, with rare exceptions, these sounds are not contrastive before plosives such as /p, t, k/ within the same morpheme. Although all three phones appear before plosives, for example in limp, lint, link, only one of these may appear before each of the plosives. That is, the /m, n, ŋ/ distinction is neutralized before each of the plosives /p, t, k/:

* Only /m/ occurs before /p/,
* only /n/ before /t/, and
* only /ŋ/ before /k/.

Thus these phonemes are not contrastive in these environments, and according to some theorists, there is no evidence as to what the underlying representation might be. If we hypothesize that we are dealing with only a single underlying nasal, there is no reason to pick one of the three phonemes /m, n, ŋ/ over the other two.

(In some languages there is only one phonemic nasal anywhere, and due to obligatory assimilation, it surfaces as [m, n, ŋ] in just these environments, so this idea is not as far-fetched as it might seem at first glance.)

In certain schools of phonology, such a neutralized distinction is known as an archiphoneme (Nikolai Trubetzkoy of the Prague school is often associated with this analysis). Archiphonemes are often notated with a capital letter. Following this convention, the neutralization of /m, n, ŋ/ before /p, t, k/ could be notated as |N|, and limp, lint, link would be represented as |lɪNp, lɪNt, lɪNk|. (The |pipes| indicate underlying representation.) Other ways this archiphoneme could be notated are |m-n-ŋ|, {m, n, ŋ}, or |n*|.

Another example from American English is the neutralization of the plosives /t, d/ following a stressed syllable. Phonetically, both are realized in this position as [ɾ], a voiced alveolar flap. This can be heard by comparing writer with rider (for the sake of simplicity, Canadian raising is not taken into account).

[ɹaɪˀt] write
[ɹaɪd] ride

with the suffix -er:

[ˈɹaɪɾɚ] writer
[ˈɹaɪɾɚ] rider

Thus, one cannot say whether the underlying representation of the intervocalic consonant in either word is /t/ or /d/ without looking at the unsuffixed form. This neutralization can be represented as an archiphoneme |D|, in which case the underlying representation of writer or rider could be |ˈɹaɪDɚ|.

Another way to talk about archiphonemes involves the concept of underspecification: phonemes can be considered fully specified segments while archiphonemes are underspecified segments. In Tuvan, phonemic vowels are specified with the articulatory features of tongue height, backness, and lip rounding. The archiphoneme |U| is an underspecified high vowel where only the tongue height is specified.

phoneme/
archiphoneme height backness roundedness
/i/ high front unrounded
/ɯ/ high back unrounded
/u/ high back rounded
|U| high

Whether |U| is pronounced as front or back and whether rounded or unrounded depends on vowel harmony. If |U| occurs following a front unrounded vowel, it will be pronounced as the phoneme /i/; if following a back unrounded vowel, it will be as an /ɯ/; and if following a back rounded vowel, it will be an /u/. This can been seen in the following words:

-|Um| 'my' (the vowel of this suffix is underspecified)
|idikUm| → [idikim] 'my boot' (/i/ is front & unrounded)
|xarUm| → [xarɯm] 'my snow' (/a/ is back & unrounded)
|nomUm| → [nomum] 'my book' (/o/ is back & rounded)


Minimal contrastive units in sign languages

In sign languages, the basic elements of gesture and location were formerly called cheremes (or cheiremes), but general usage changed to phoneme. Tonic phonemes are sometimes called tonemes, and timing phonemes chronemes.

In sign languages, phonemes may be classified as Tab (elements of location, from Latin tabula), Dez (the hand shape, from designator), Sig (the motion, from signation), and with some researchers, Ori (orientation). Facial expressions and mouthing are also phonemic.

There is one published set of phonemic symbols for sign language, the Stokoe notation, used for linguistic research and originally developed for American Sign Language. Stokoe notation has since been applied to British Sign Language by Kyle and Woll, and to Australian Aboriginal sign languages by Adam Kendon. Other sign notations, such as the Hamburg Notation System and SignWriting, are phonetic scripts capable of writing any sign language. However, because they are not constrained by phonology, they do not yield a specific spelling for a sign. The SignWriting form, for example, will be different depending on whether the signer is left or right handed, despite the fact this makes no difference to the meaning of the sign.

Phonological extremes

Of all the sounds that a human vocal tract can create, different languages vary considerably in the number of these sounds that are considered to be distinctive phonemes in the speech of that language. Ubyx and Arrernte have only two phonemic vowels, while at the other extreme, the Bantu language Ngwe has 14 vowel qualities, 12 of which may occur long or short, making 26 oral vowels, plus 6 nasalized vowels, long and short, making a total of 38 vowels; while !Xóõ achieves 31 pure vowels, not counting its additional variation by vowel length, by varying the phonation. Rotokas has only six consonants, while !Xóõ has somewhere in the neighborhood of 77, and Ubyx 81. French has no phonemic tone or stress, while several of the Kam-Sui languages have nine tones, and one of the Kru languages, Wobe, has been claimed to have 14, though this is disputed. The total phonemic inventory in languages varies from as few as eleven in Rotokas to as many as 112 in !Xóõ (including four tones). The English language uses a rather large set of 13 to 21 vowels, including diphthongs, though its 22 to 26 consonants are close to average. (There are 21 consonant and five vowel letters in the English alphabet, but this does not correspond to the number of consonant and vowel sounds.)

The most common vowel system consists of the five vowels /i/, /e/, /a/, /o/, /u/. The most common consonants are /p/, /t/, /k/, /m/, /n/. Very few languages lack any of these: Arabic lacks /p/, standard Hawaiian lacks /t/, Mohawk and Tlingit lack /p/ and /m/, Hupa lacks both /p/ and a simple /k/, colloquial Samoan lacks /t/ and /n/, while Rotokas and Quileute lack /m/ and /n/.

Tidak ada komentar:

Posting Komentar