Metrical phonology

Metrical phonology is a theory of stress or linguistic prominence. The innovative feature of this theory is that the prominence of a unit is defined relative to other units in the same phrase. For example, in the most common pronunciation of the phrase "doctors use penicillin" (if said out-of-the-blue), the syllable '-ci-' is the strongest or most stressed syllable in the phrase, but the syllable 'doc-' is more stressed than the syllable '-tors'. Previously, generative phonologists and the American Structuralists represented prosodic prominence as a feature that applied to individual phonemes (segments) or syllables. This feature could take on multiple values to indicate various levels of stress. Stress was assigned using the cyclic reapplication of rules to words and phrases.

Metrical phonology holds that stress is separate from pitch accent and has phonetic effects on the realization of syllables beyond their intonation, including effects on their duration and amplitude. The perceived stress of a syllable results from its position in the metrical tree and metrical grid for the phrase it appears in.

Linguistic prominence in metrical phonology is partially determined by the relations between nodes in a branching tree, in which one node is Strong (S) and the other node or nodes are Weak (W). The labels Strong and Weak have no inherent phonetic realization, and only have meaning relative to the rest of the labels in the tree. A Strong node is stronger than its Weak sister node. The most prominent syllable in a phrase is the one that does not have any Weak nodes above it. This syllable is called the Designated Terminal Element. In the example tree (1), the syllable '-ci-' is the Designated Terminal Element.

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