Distinctive Features - Speech Resource Pages - Macquarie University

d) Gradual Oppositions
The members of a class of sounds possess different degrees or gradations of a
feature or property. For example, the three short front unrounded vowels in
English /ɪ, e, æ/ which are distinguished only by their height. In this system
height would be a single feature with two or more degrees of height.
e) Equipollent Oppositions
The relationship between two members of an opposition are considered to be
logically equivalent. Consonant place of articulation can be seen in this sense.
Changes in place involve not just degree of fronting but also involve other
articulator changes.
3. Roman Jakobson et al. (1941-1956)
Roman Jakobson was also a member of the Prague school of linguistics and
worked closely with Trubetzkoy. Distinctive feature theory, based on his own
work and the work of Trubetzkoy, was first formalised by Roman Jakobson in
1941 and remains one of the most significant contributions to phonology. Briefly,
Jakobson's original formulation of distinctive feature theory was based on the
following ideas:-
1. All features are privative (ie. binary). This means that a phoneme either
has the feature eg. [+VOICE] or it doesn't have the feature eg. [-VOICE]
2. There is a difference between PHONETIC and PHONOLOGICAL FEATURES
o Distinctive Features are Phonological Features.
o Phonetics Features are surface realisations of underlying
Phonological Features.
o A phonological feature may be realised by more than one phonetic
feature, eg. [flat] is realised by labialisation, velarisation and
pharyngealisation
3. A small set of features is able to differentiate between the phonemes of
any single language
4. Distinctive features may be defined in terms of articulatory or acoustic
features, but Jakobson's features are primarily based on acoustic
descriptions
Jakobson and colleagues (Jakobson, Fant and Halle, 1952, Jakobson and Halle,
1956) devised a set of 13 distinctive features. They are not reproduced here, but
they represent a starting point for the set defined by Chomsky and Halle.
4. Chomsky and Halle (1968-1983)
Distinctive feature theory was first formalised by Roman Jakobson in 1941. There
have been numerous refinements to Jakobson's (1941) set of features, most
notably with the development of Generative Phonology and the publication of
Chomsky & Halle's (1968) Sound Pattern of English but also from phoneticians
such as Ladefoged (1971), Fant (1973) and also Stevens (Halle & Stevens, 1971).
In recent years, there have also been proposals that features should themselves
be hierarchically structured and arranged on separate levels or tiers (e.g.
Clements & Keyser, 1983) which is consistent with the developments in
autosegmental phonology since the publication of the Sound Pattern of English.