2 - Speech Perception in the Absence of Speech Productive Ability

Abstract

This chapter describes speech perception in the absence of speech productive ability. The ability of the hearing mechanism to process the temporal order of stimuli, respond to formant peaks, and analyze the periodicities of an input into pitch percepts is necessary whether an articulatory or acoustic theory of speech perception is at issue and the interpretation of the results of this analysis could also be the same if the second possibility for vocal tract normalization described above is employed. Liberman has criticized the inference that motor knowledge has no part to play in speech perception in these cases supposing that this knowledge was in fact acquired during a babbling period. Although work has been done that was specifically directed to the study of acoustic-pattern normalization in speech perception, critical tests of the approach have yet to be made. One way of at least beginning to solve this problem is by obtaining the assistance of congenitally speechless listeners in speech-perception experiments that depend on the exercise of primarily auditory skills.