stress phonology

STRESS

Stress is a suprasegmental feature of utterances. It applies not to individual vowels and consonants but to whole syllable – whatever they might be. A stressed syllable is pronounced with a greater amount of energy than an unstressed syllable and is more primainent in the flow of speech.

English and other Germanic languages make far more use of differences in stress than do most of the languages of the world. In many languages, the position of the stress is fixed iin relation to the word. Czech words nearly always have the stress on the first syllable, irrespective of the number of syllables in the word. In polish and Swahili, the stress is usually on the penultimate syllable.

Variation in the use of stress cause different languages to have different rhythms, but stress is only one factor in causing rhythmic differences. Because it can appear to be a major factor , it used to be said that some languages (such as french) could be called syllable – timed languages, in which syllables tned to recur at regular intervals of time. In contrast, English and pother Germanic languages were called stress – timed in that stressese were said to be dominating feature of the rhythmic timing. We now know that is not true. In contemporary French there are aften strong stresses breaking the rhythm of a sentence. In English the rhythm of a sentence depends on several interecting factors, not just the stress. Perhaps a better way describing stress deffer ences among languages would be to divide languages into those that have variable word stress (such as English and Germanic ) those that have fixed word stress (such as Czech , Polish , and Swahili ), and those that have fixed phrase stress (such as Frenc ).

In contrast to the nature of syllable , the nature of stress is fairly well understood. Stressed sounds are those on the speaker expends more muscular energy. This usually involves pushing out more air from the lungs by contracting the muscles of the rib cage, and perhaps increasing the pitch by the use of the laryngeal mucles. The extra activity may result in giving the sound greater length. There may also be increases in the muscular activity involved in the articulary movements.

When there is an increase in the amount of air being pushed out of the lungs, there is increase in the loudness of the sound produced. Some books define stress simply in terms of loudness, but this is not a very useful definition if loudness considered to be simply a metter of te amount of acoustic energy involved. We have already noted that some sounds have more acoustic energy than others because of factors such as the degree of mount opening.

A much more important indication of stress iin the rise in pitch, which may or may not be due to laryngeal action. You can check for your self that an increase in the flow of air out of the lungs causes a rise in pitch even without an increase in the activity of the laryngeal muscles. Ask a friend to press against the lower part of your chest while you stand against a wall with your eyes shut. Now say a ong vowel on a steady ptch and have your friend push against your chest at an unexpected moment. You will find that at the same time as there is an increase in the flow of air out of your lungs (as a result of your friend’s push), there will also be an increase in the pitch f the vowel.

There is final factor to note when discussing stress in English. We saw in charpter 5 that a syllable in English is either stressed or not stressed. If it is stressed it can be at the center of an intonational ptch change so that it receives a tonic accent, which might be said to raise it to a more primary level of stress. If it is unstressed it can have a full vowel or a reduced vowel. In some views, a reduced vowel implies that there is a lower level of stress, but in the view expressed here this is not a metter of stress but of vowel quality. We also saw that there are pairs of words, such as ‘(an) insult’ and (to) insult that differ only in stress. What happens when these words appear to lose their stress because of a heavy stress elsewhere in the sentence ? consider a pair of sentences such as ‘he need an increase in price’ and, with an equally strong stress on ‘needed’, ‘he needed to increase the price’. The answer in that the stress difference between the two words is not completely lost. There may be no changes in pitch associated with the difference in stress, but there are still differences in the relative lengths of the syllables. A stressed syllable is pronounced with a greater amount of energy than an unstressed syllable, and this difference may be manifested simply in the length of the syllable.