The perceptual similarity of mirror-image acoustic patterns in speech

Prevocalic and postvocalic (unreleased) occurrences of a stop consonant differ in acoustic shape, but are not unrelated. In particular, the formant transitions taking place at release of a stop consonant approximately mirror in time the formant transitions occurring during closure, assuming that the vowel is the ~same. Several experiments have been performed using brief two-component tone burst approximations to the second and third formant transitions’ that occur in prevocalic and postvocalic allophones of/b, d, g/in order to determine whether such mirror-image acoustic patterns are perceptually related. Listener judgments of similarity within triads of these stimuli indicate that mirror-image patterrts representing the same place of articulation are less similar to each other than to patterns representing different places of articulation. Implications for the child who is acquiring language of the fact that mirror-image patterns in speech do not have inherent perceptual similarity are discussed.