autosegmentale

Autosegmental phonology is a theoretical framework in linguistics for modeling phonological structure in which phonological features are represented on separate, parallel tiers (autosegments) rather than being tied to a single linear string of segments. Developed in the 1970s, most prominently by John Goldsmith, the approach aims to capture phenomena that do not fit neatly into a one-to-one correspondence between segments and features. In this model, a phonological representation consists of multiple tiers, such as a segmental tier for consonants and vowels, a tonal tier for pitch, and sometimes a nasal or vowel-quality tier. Association lines link features on their respective tiers to the segments they affect.

The core idea is that segments are independent entities, and features can spread, delete, or associate with different segments across time. This allows the analysis of nonconcatenative or multi-dimensional processes, such as tone that operates independently of the segmental string, or tone that spreads across a word. The framework also supports analysis of alignment and metrical structure via multi-tier representations. A major development, autosegmental-metrical phonology (AM), integrates a metrical tier to model stress and syllable structure alongside segmental and tonal tiers.

Impact and applications: Autosegmental theory has been influential in analyses of tone languages, vowel harmony, nasalization, and other phenomena where features are best represented separately from segments. It provided a foundation for nonlinear phonology and informed subsequent models of phonological representation and processing. Critics have pointed to complexity and interpretive variability, but the approach remains a foundational concept in the study of multi-tier phonological structure.