Autosegmental phonology

Autosegmental phonology is a modification of generative phonology introduced by John Goldsmith in his PhD thesis in 1976.

The main idea of autosegmental theory is that phonology no longer regards the phenomena it studies as a linear sequence of phonemes and a collection of processes which describe the changes which occur in this sequence. Goldsmith proposes to represent phonological phenomena as a collection of parallel tiers with individual segments which represent certain features of speech. Various feature systems have been proposed. Depending on the nature of the study already a few can explain phenomena which are difficult to explain otherwise. An example would be one tier representing the conventional segments (in the sense of phonemes) and an additional tier representing tone. (see tone language)

Autosegmental phonology has served as the foundation for further developments in phonology such as nonconcatenative morphology.