Invariance of speech percepts

Abstract

A fundamental question is about the invariance of the ultimate, percepts or features. The present paper gives an overall picture of the issues relevant to this question, aiming at finding a solution. A discussion of the main elements contributing to invariance will be made explicit, namely coupling and interaction. The main question will be that of the principles guiding coupling and interaction during perceptual development. The conclusion of this research work is that perceptual invariance appears to be based on a radial representation of the vocal tract around a singular point at which boundaries are context-free, natural and coincide with the neutral vocoid.