Phonology: Distinctive Features

Distinctive Features

• Distinctive features are the universal set of cognitive properties associated with speech sounds that define classes of sounds relevant to phonology.
• They determine the contrasts between speech sounds, account for the ways in which these sounds may change or alternate, and define the sets of sounds.

Feature System

• The formal development of distinctive feature theory is due primarily to Roman Jakobson.
• Only binary oppositions are accepted [ +/-], and features will have two values: [+feature] and [-feature] to indicate the presence or absence of that particular feature.
• Example: [b] is [+voice] and [p] is [-voice]

Feature Characteristics

• Features are the most basic units of phonology, like atoms, and are phonetically grounded elements.
• Segments (speech sounds) and syllables are the basic building blocks of speech sounds.

Patterns of Patterns

• Sometimes, the rules for one phoneme's distribution are identical to the rules for another phoneme's distribution.
• Examples: /t/→ [t] / after [s], /t/ → [th] / at the beginning of stressed syllables, and [stɑp] ‘stop’ & [thɑp] ‘top’.

Natural Classes

• A natural class is a set of sounds in a language that:
  • Share one or more phonetic features.
  • To the exclusion of all other sounds in that language.
  • Function together in phonological rules.
• Example: /p/, /t/, and /k/ form a natural class of voiceless stops in English.

Natural Class Examples

• In English, [k], [ɡ], and [ŋ] form the natural class of velar stops.
• [uː] and [ɔː] form the natural class of rounded, tense vowels.
• Exercises:
  • [t], [s]
  • [v], [ð], [z], [ʒ]
  • [ɪ], [ɛ], [æ]

Phonological Problem: Arabic

• In Arabic, consonants are divided into two groups: حروف قمریة (Moon-letters) and حروف شمسیة (Sun-letters).
• The classification is based on whether or not they assimilate the definite article ال [ʔal].
• When the definite article [ʔal] is assimilated into the Sun-letters, it loses its distinctive sound, and the sound at the beginning of the word is doubled.
• Example: ال ّرحمن (Given Shaddah).