Linguistic Units and Speech Production Theory

Abstract

Today, one seldom hears of the unit of speech production. Speech error data, in particular, have made it clear that every linguistic unit from “phonemic phrase” through “word,” “morpheme,” “syllable,” and “phoneme” to “distinctive feature” is useful to the speech production theorist in that each allows him to conceptualize processes whereby the speaker manipulates unitary variables in his output. As some of these units must be “activated” prior to others in the organization of output, and as some units actually overlap structurally with others, we require a hierarchical model specifying the sequence of events leading to output and resolving problems of overlap. Some clues to the form of this model are available. Very little is known about the higher order units—phonemic phrase, word, morpheme—in this regard. For the lower-order units much conceptual difficulty remains, including questions asked to the physical manifestation of the syllable, and the inventory of phonemes and features. Most work in linguistic science proper has been of limited assistance here because of its virtually sole concern with contrastive properties of speech, and its failure to conceptually distinguish production from perception. Problems of sampling and interpretation may also limit further profit from speech error data. The most basic problem of speech production theory has always been that although speech must be conceptualized in terms of units, a speaker's output is a continuous strain in which movements of various articulators overlap in space and time. Studies of the dynamics of these movement sequences show promise of providing the best empirical base for theory of speech production in which linquistic units and observable physical processes are reconciled. Consideration of timing mechanisms and rhythmic organization will be a prerequisite to such a theory, and sets of rules relating citation form speech to spontaneous speech must be included. The invariants in this theory will be found in the goals being attempted rather than in the means being used to achieve them.