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Distinctive Features

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Distinctive Features
As we studied Phonetics we saw there are dozens of sounds in every natural
language of human beings that we consider as phonemes, which play the most
significant role in producing words by arranging structurally in a constructive
manner. Now we know every sound production takes place in a different way
i.e. every speech sounds have its manner and point of articulation. We
distinguish these speech sounds in terms of their features which are
determined by their manner and point of articulation. We label them as vowels
and consonants i.e. if there is constriction or friction in the vocal tract we call
those sounds consonants and if there is no constriction we just call them
vowels.
These are the most basic things we already know about speech sounds, before
entering to distinctive features in a proper manner we had to recapitulate
these foundational things for once.
What is a Distinctive feature?
Distinctive features enable us to describe the segments in the world’s
languages and to refer to those groups of segments that play a role in their
characteristic phonological process and constraints.
These are the elements by which we can refer to natural segment classes,
groups of segments that are treated as groups by languages.
Distinctive features are always binary, so they always have either a positive or
a negative specification, e.g. [+voice] as for [b] and [-voice] as for [p].
Why we study Distinctive features
When we talk about phonemes, we deal with the smallest unit of any language
which is speech sounds. These are very specific and limited in every human
language. A limited number of phonetic parameters, taken from a fairly small
universal set recur in a variety of combinations in different languages. It makes
us go beyond the phoneme and focus on those basic phonological ingredients,
called Distinctive features.
Every language has its Phoneme system which is constructed by a relatively
small inventory of phonetic features. The combinations of phonemes in every
language are different. The human evaluation took place at one time with
every member of the human family, thus the vocal apparatus of every human
being are consist of the same organs, and thus the point and manner of
articulations are the same for every human being. It’s the biological or genetic
conditioning for which every linguistic community has its different phonemic
usage. We can distinguish or establish separate phonological features of that
specific linguistic community in terms of that usage.
We can show an example to make a justification in favor of the need for
Distinctive features.
Pray
[pr̥eɪ]
brain [breɪn]
In this example, we can see the phenomenon with /r/ takes place in English,
that It undergoes partial devoicing when immediately preceded by voiceless
stops but not when it is preceded by voiced ones.
If we talk about phoneme /r/, we know it’s voiced, trill sound by the manner,
and alveolar by the point of articulation. Here in the example when the word
starts with a voiceless stop like /p/, phoneme /r/ is getting partially devoiced at
the same time when the word starts with a voiced stop sound like /b/,
phoneme /r/ is not getting devoiced. So in a way we can observe that
precedence is the factor here which we call Assimilation in Phonology when
the initial phoneme injects its nature into the next phoneme. By highlighting
each articulatory parameter and singling out the sub-phonemic particles (i.e.
distinctive features) of which phonemes are made up, this approach is capable
of treating assimilation insightfully as an instance of Spreading of distinctive
features.
A brief history of Prague school
Russian Phonologists Nicolai Trubetzkoy and Roman Jakobson were the
founders of the Prague school which is mainly known for their revolutionary
contribution to Generative phonology. As American linguists considered a
phoneme as the basic unit of any language, phonologists of the Prague school
countered this concept by establishing the concept of Distinctive features. For
example, in English, /b/ differs from /p/ in the same way that /d/ differs from
/t/ and /g/ from /k/. Similarly, the feature of labiality can be extracted from /p/
and /b/ by comparing them with /t/, /d/, /k/, and /g/; the feature of nasality
from /n/ and /m/ by comparing them with /t/ and /d/, on the one hand, and
with /p/ and /b/, on the other. Each phoneme, then, is composed of several
articulatory features and is distinguished by the presence or absence of at least
one feature from every other phoneme in the language.
The distinctive function of phonemes, which depends upon and supports the
principle of the duality of structure, can be related to the cognitive function of
language. This distinctive feature analysis of Prague school phonology as
developed by Jakobson became part of the generally accepted framework for
generative phonology which was led by Chomsky afterward.
Features proposed by Jakobson, Fant, and Halle (1952)
Prague school Phonologists categorized the concept of Distinctive features into
three major parts:
a. Fundamental Source Features
b. Secondary Consonantal Features
c. Resonance Features
Fundamental Source Features
This feature can be subcategorized into two subdivisions.
• Vocalic vs non vocalic: Oral cavity plays a significant role in the
production of vocalic sounds where the most radical constriction
does not exceed. We can find these features in high vowels e.g. [i]
and [u]. the position of the vocal cords allows the spontaneous
voicing.
In non vocalic sounds, one or both of these conditions are not
satisfied.
e.g. vocalic sounds: (/a,o,u/) and liquids (/l,r/)
non vocalic sounds: glides (/w,y/), nasal consonants (/m,n,
ɳ,ŋ/), obstruents i.e. plosives, fricatives and affricates (/p,f/) and
voiceless vowels and liquids (/ ɑ̥ ,ɻ/̥ )
• Consonantal vs non-consonantal: In the production of consonantal
sounds a huge obstruction takes place in the main region of the
vocal tract whereas non-consonantal sounds are produced
without such an obstruction.
e.g. consonantal sounds: liquids, nasal consonants, non-nasal
consonants.
Non-consonantal: voiced vowels, voiceless vowels, glides
Secondary Consonantal Features
This feature can be subcategorized into four subdivisions.
• Interrupted vs Continuant: Interrupted and Continuant are
actually two types of consonants that are distinguished by abrupt
onset. The main characteristic of Interrupted consonants is a
sharp wavefront preceded by a period of complete silence, for
which, under certain conditions, a mere vibration of the vocal
bands may be substituted.
Continuant sounds are produced in a way where the primary
constriction in the vowel tract is not blocked; in stops, the airflow
through the mouth is effectively blocked.
e.g. Interrupted: stops (/p,b,t,d/)
Continuant: everything else (/f,v,m,r/)
• Checked vs Unchecked: In spectrograms, checked phonemes are
marked by a sharper termination, which lacks in unchecked.
• Strident vs Mellow: Strident sounds have an irregular waveform
which is represented by a random distribution of black areas in
the spectrogram, whereas Mellow sounds have a regular
waveform and have a spectrogram with black areas which may
form horizontal or vertical striations.
Plosives are nonstrident stops and affricates are strident stops.
• Voiced vs Unvoiced: The spectrum of voiced consonants includes
formants that are due to the harmonic source. The most striking
manifestation of "voicing" is the appearance of a strong low
component which is represented by the voice bar along the
baseline of the spectrogram. Voiced phonemes are emitted with
periodic vibrations of the vocal bands and voiceless phonemes
without such vibrations.
e.g. Voiced: (/b,d,g/)
Voiceless: (/p,t,g/)
Resonance Features
Resonance features can be subcategorized into six subdivisions again.
• Compact/diffuse & Grave/acute:
1. Compact phonemes are characterized by the relative
predominance of one centrally located formant region (or
formant). They are opposed to diffuse phonemes in which
one or more non-central formants or formant regions
predominate.
2. Acoustically this feature means the predominance of one
side of the significant part of the spectrum over the other.
When the lower side of the spectrum predominates, the
phoneme is labeled grave; when the upper side
predominates, we term the phoneme acute
Arabic
e.g.
a
Compact
diffuse
u
grave
I
acute
• Flat/plain: • Flattening manifests itself by a downward shift of a
set of formants or even of all the formants in the spectrum …
Flattening is chiefly generated by a reduction of the lip orifice
(rounding) with a concomitant increase in the length of the lip
constriction. Hence the opposition flat vs. plain has been
genetically termed "orifice variation", and the opposition grave vs.
acute "cavity variation"
• Sharp/plain: This feature manifests itself in a slight rise of the
second formant and, to some degree, also of the higher formants.
To effect this feature, the oral cavity is reduced by raising a part of
the tongue against the palate.
• Tense/Lax: In contradistinction to the lax phonemes the
corresponding tense phonemes display a longer sound interval
and larger energy. In contradistinction, to the lax phonemes, the
corresponding tense phonemes display a longer sound interval
and larger energy. Tense sounds are produced with a deliberate,
accurate, maximally distinct gesture that involves considerable
muscular effort; nontense sounds are produced rapidly and
somewhat indistinctly.
• Nasal/Oral: Nasal sounds are produced with a lowered velum
which allows the air to escape through the nose; nonnasal sounds
are produced with a raised velum so that the air from the lungs
can escape only through the mouth.
e.g. orals are (/p,b/) and nasals are (/m,n/)
Distinctive features in The Sound Pattern of English
As there are some class features according to SPE proposed by Chomsky and
Halle, we’ll discuss some of them
1. Major class features
2. laryngeal features
3. manner features
• Major class features:
1. [±consonantal], [+Cons] segments have a constriction
somewhere along the center line in the vocal tract
which is as narrow as that required for a fricative (e.g.
plosives, affricates, nasals, laterals and [r])
[-cons] segments lack such a constriction. (e.g.
vowels, glides [ʝ ɦʔ]
2. [±sonorant] . [+son] segments are produced with a
con striction in the vocal tract which allows the air
pressure behind it and in front of it to be relatively
equal, while this is not the case for [−son] segments.
e.g. [h] and [ʔ] are [−son] and [+son] are all vowels,
glides like [ʋ w j], liquids and nasals.
3. [±approximant], [+approx] are those segments which
have a constriction in the vocal tract which allows a
free (frictionless) escape of air, while for [−approx]
segments this is not the case.
e.g. Vowels and non-nasal sonorants, like [1 ɹ ʌ], are
[+approx] segments
• Laryngeal Features:
1. [±voice]. [+voice] are segments for which the vocal
folds are close enough together to allow vibration,
while for [−voice] this is not the case. Thus,
[+voice] are vowels (e.g. [i ʌ ɛ̃ aɪ]), sonorant
consonants (e.g. [m ɲ l r ʀ w]) and voiced
obstruents (e.g. [b z ɣ dʒ] and [ɦ]), while [−voice]
are voiceless obstruents (e.g. [p θ ʃ ts h])
2. [±spread glottis]. [+spread] segments have a vocal
fold configuration that produces audible friction in
the glottis, while [−spread] segments lack such a
configuration. Thus, aspirated segments like [ph
kwh] and [h ɦ] are [+spread], while other
segments are [−spread].
3. [±constricted glottis]. For [+constr] segments the
vocal folds are tense and drawn together, while
for [−constr] segments this is not the case. Thus,
[ʔ], laryngealized vowels (e.g. [ṵ]) and
laryngealized sonorant consonants (e.g. [mʔ ]),
glottalized obstruents (e.g. preglottalized [ˀp] or
ejective [p’]) are [+constr]. So are implosives ([ɓ ɗ
ɠ]). Other segments are [−constr].
• Manner Features:
1. [±continuant]. [+cont] segments lack a central
occlusion in the vocal tract, while [−cont]
segments are produced with such an occlusion.
Thus, plosives (e.g. [p d g]), nasal consonants
(e.g. [m ŋ]), affricates (e.g. [tʃ]) and later als
(e.g. [l]) are [−cont], and other segments are
[+cont]. Some languages apparently treat
laterals as [+cont], which is phonetically
understandable in the sense that while these
segments have a central occlusion, they have a
lateral aperture.
2. [±nasal]. [+nas] segments (e.g. [m n ŋ]) are
produced with the velum (‘soft palate’)
lowered, and [−nas] segments have the velum
in its closed (raised) position. Nasal consonants
and nasalized vowels are [+nas]; other
segments are [−nas].
3. [±strident]. [±strident] is relevant for
obstruents only and refers to a type of
friction.[+strident]segments cause anoisier
kind offrictionthan[−strident] segments.
[+strident] voiceless fricatives are [f s ʃ χ];
[−strident] ones are [θ ç x].
We discussed Distinctive Features with a very
basic understanding. As there are more
features to discuss that we were unable to
discuss in this essay. All over we can say that
the Distinctive feature is a revolutionary
invention in generative phonology.
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