La invariación acústica: introducción

Abstract

The obvious variation of F2 transitions for equal place of articulation, due to the influence of the following vowel, provided Liberman et col. (1967) with evidence against the existence of invariant acoustic parameters in speech perception. They claimed that there was invariance in the motor mechanisms of speech production. However, Stevense's quantal theory (1972) and the phenomenon of categorical perception made it clear that the articulatory cavities produce steady acoustic patterns which can be captured by the human perceptive system, thus limiting substantially the number of phonic patterns that can be used in a language. So then, these restrictions support the existence of acoustic invariant cues that can be processed by the human perceptive system. Having this hypothesis as basis, we have carried out various studies seeking invariant acoustic parameters for the sounds of Spanish, with the aim that this will serve us to implement an automatic speech recognition model based on phonetic features.