Prosody (linguistics)

In linguistics, prosody (from Greek "προσωδία") is the rhythm, stress, and intonation of speech. Prosody may reflect the emotional state of a speaker; whether an utterance is a statement, a question, or a command; whether the speaker is being ironic or sarcastic; emphasis, contrast and focus; and other elements of language which may not be encoded by grammar.

Acoustic attributes of prosody

Acoustically, the prosodics of oral languages involves variation in syllable length, loudness, pitch, and the formant frequencies of speech sounds. In Cued Speech and sign languages, prosody involves the rhythm, length, and tenseness of gestures, mouthing, and facial expressions. Prosody is notoriously difficult to convey in writing, which is one reason why, for example, email may so easily cause misunderstanding. Orthographic conventions to convey prosody include punctuation such as commas, exclamation marks, question marks, scare quotes, and ellipses; forms of emphasis such as italic, bold, and underlined text; and emoticons.

The details of prosody will depend upon the phonology of a language. For instance, in a language with phonemic vowel length, this must be kept distinct from prosodic syllable length. Likewise, prosodic pitch cannot obscure tone in a tone language if the result is to be intelligible. Although a tone language such as Mandarin will use pitch variations for prosody, they will occur at a different level than the pitch variations involved in lexical and grammatical tone. If pitch can be compared to ocean waves, the swells are the prosody, and the wind-blown ripples in their surface are the lexical tones. That is, the pitch corresponding to a "mid" tone may rise or fall with prosody, but it will retain its relative position compared to "high" and "low" tones. This is similar to stress in English: The word "dessert" has greater stress on the second syllable, compared to "desert," which has greater stress on the first, but this distinction is not obscured when the entire word is stressed by a child demanding "Give me dessert!" Vowels in many languages are likewise pronounced differently (typically less centrally) in a careful rhythm or when a word is emphasized, but not so much as to overlap with the formant structure of a different vowel. Thus rhythm, loudness, pitch, and vowel formants convey a mixture of lexical and prosodic information.

The prosodic domain

Prosodic features are suprasegmental in that they are not confined to any one segment; rather, they occur in a hierarchy of higher levels of an utterance. These prosodic units are the actual phonetic spurts or chunks of speech. They do not in general correspond to grammatical units such as phrases, and clauses, though they may, and both may reflect how the brain processes speech.

Prosodic units are characterized by several phonetic cues, such as a coherent pitch contour, and the gradual decline in pitch and lengthening of vowels over the duration of the unit, until the pitch and speed are reset to begin the next unit. Breathing, both inhalation and exhalation, only seems to occur at these boundaries where the prosody resets.

Prosody and emotion

Emotional prosody describes the perception of feelings expressed in speech, and was recognized by Charles Darwin in "The Descent of Man" to predate the evolution of human language: "Even monkeys express strong feelings in different tones — anger and impatience by low, fear and pain by high notes." [cite web|url=http://www.infidels.org/library/historical/charles_darwin/descent_of_man/chapter_19.html|title=The Descent of Man|year=1871|author=Charles Darwin "citing" Johann Rudolph Rengger, Natural History of the Mammals of Paraguay, s. 49] Native speakers listening to actors reading neutral text to project emotions were able to recognize happiness 62%, anger 95%, surprise 91%, sadness 81%, and neutral tone 76% correctly in trials. When a database of this speech was processed by computer, segmental features allowed >90% recognition of happiness and anger, while supra-segmental prosodic features allowed only 44-49% recognition. The reverse was true of surprise, which was recognized only 69% by segmental features and 96% by supra-segmental prosody. [cite web|url=http://www-gth.die.upm.es/research/documentation/AG-39Pro-06.pdf|title=Prosodic and segmental rubrics in emotion identification|author=R. Barra, J.M. Montero, J. Macías-Guarasa, L.F. D’Haro, R. San-Segundo, R. Córdoba]

References

ee also

* Intonation
* Phonological hierarchy