Aspiration (phonetics)

In phonetics, aspiration is the strong burst of air that accompanies either the release or, in the case of preaspiration, the closure of some obstruents. To feel or see the difference between aspirated and unaspirated sounds, one can put a hand or a lit candle in front of his or her mouth, and say "tore" (IPA| [tʰɔɹ] ) and then "store" (IPA| [stɔɹ] ). One should either feel a puff of air or see a flicker of the candle flame with "tore" that one does not get with "store". In English, the "t" should be aspirated in "tore" and unaspirated in "store".

The diacritic for aspiration in the International Phonetic Alphabet is a superscript "h", IPA| [ʰ] . Unaspirated consonants are not normally marked explicitly, but there is a diacritic for non-aspiration in the Extensions to the IPA, the superscript equal sign, IPA| [⁼] .

Description

Voiceless consonants are produced with the vocal cords open and voiced consonants are produced when the vocal folds are fractionally closed. Voiceless aspiration occurs when the vocal cords remain open after a consonant is released. An easy way to measure this is by noting the consonant's voice onset time, as the voicing of a following vowel cannot begin until the vocal cords close.

Usage patterns

English voiceless stop consonants are aspirated for most native speakers when they are word-initial or begin a stressed syllable, as in "pen", "ten", "Ken". They are unaspirated for almost all speakers when immediately following word-initial s, as in "spun", "stun", "skunk". After s elsewhere in a word they are normally unaspirated as well, except when the cluster is heteromorphemic and the stop belongs to an unbound morpheme; compare dis [t] end vs. dis [tʰ] aste. Word-final voiceless stops optionally aspirate.

Aspirated consonants are not always followed by vowels or other voiced sounds; indeed, in Eastern Armenian, aspiration is contrastive even at the ends of words. For example compare: IPA|bard͡z "pillow", with IPA|bart͡s⁼ "difficult" and IPA|bart͡sʰ "high".

In many languages, such as the Chinese languages, Indo-Aryan languages (from Sanskrit), Dravidian languages (i.e. under the influence of Sanskrit. Tamil, the classical Dravidian tongue does not show aspiration at all), Icelandic, Korean, Thai, and Ancient Greek, IPA| [p⁼ t⁼ k⁼] "etc." and IPA| [pʰ tʰ kʰ] "etc." are different phonemes altogether.

Alemannic German dialects have unaspirated IPA| [p⁼ t⁼ k⁼] as well as aspirated IPA| [pʰ tʰ kʰ] ; the latter series are usually viewed as consonant clusters. In Danish and most southern varieties of German, the "lenis" consonants transcribed for historical reasons as IPA|<b d g> are distinguished from their "fortis" counterparts IPA|<p t k> mainly in their lack of aspiration.

Icelandic and Faroese have pre-aspirated IPA| [ʰp ʰt ʰk] ; some scholars interpret these as consonant clusters as well. Preaspirated stops also occur in some Sami languages; e.g. in Skolt Sami the unvoiced stop phonemes IPA|p, IPA|t, IPA|c, IPA|k are pronounced preaspirated (IPA|ʰp, IPA|ʰt IPA|ʰc IPA|ʰk) when they occur in medial or final position.

There are degrees of aspiration. Armenian and Cantonese have aspiration that lasts about as long as English aspirated stops, as well as unaspirated stops like Spanish. Korean has lightly aspirated stops that fall between the Armenian and Cantonese unaspirated and aspirated stops, as well as strongly aspirated stops whose aspiration lasts longer than that of Armenian or Cantonese. (See voice onset time.) An old IPA symbol for light aspiration was IPA| [ ʻ ] (that is, like a rotated ejective symbol), but this is no longer commonly used. There is no specific symbol for strong aspiration, but IPA| [ʰ] can be iconically doubled for, say, Korean *IPA| [kʻ ] vs. *IPA| [kʰʰ] . Note however that Korean is nearly universally transcribed as IPA| [k] vs. IPA| [kʰ] , with the details of voice onset time given numerically.

Aspiration also varies with place of articulation. Spanish /p t k/, for example, have voice onset times (VOTs) of about 5, 10, and 30 milliseconds, whereas English /p t k/ have VOTs of about 60, 70, and 80 ms. Korean has been measured at 20, 25, and 50 ms for IPA|/p t k/ and 90, 95, and 125 for IPA|/pʰ tʰ kʰ/.

Usage of IPA| [ʰ]

The word 'aspiration' and the aspiration symbol is sometimes used with voiced stops, such as IPA| [dʰ] . However, such "voiced aspiration", also known as "breathy voice" or "murmur", is less ambiguously transcribed with dedicated diacritics, either IPA| [d̤] or IPA| [dʱ] . (Some linguists restrict the subscript diacritic IPA| [ ̤] to sonorants, such as vowels and nasal consonants, which are murmured throughout their duration, and use the superscript IPA| [ʱ] for the murmured release of obstruents.) When murmur is included under the term aspiration, "voiceless aspiration" is called just that to avoid ambiguity.

References

*Taehong Cho and Peter Ladefoged, "Variations and universals in VOT". In "Fieldwork Studies of Targeted Languages V: UCLA Working Papers in Phonetics" vol. 95. 1997.

ee also

*Voice onset time
*List of phonetic topics
*Phonation
*Preaspiration
*"Spiritus asper"
*"Spiritus lenis"