Theoretical implications of the quantal nature of speech: a commentary

Abstract

The relation between the quantal theory of speech and a theory of acoustic invariance and distinctive feature theory is considered. Certain aspects of the quantal theory are questioned including the role of the proximity of two formants in defining quantal regions and the extent to which there is an “abrupt” change in the boundary regions between two quantal regions. Nevertheless, it is argued that the quantal theory provides the basis for a theory of acoustic invariance and distinctive feature theory. Issues that have yet to be resolved include whether the same acoustic properties necessarily generalize across different sound classes, whether all distinctive features have their basis in quantal relations, whether the particular distinctive features proposed are the correct ones, and the exact characterization of the nature of the acoustic properties corresponding to the full set of distinctive features.