The auditory representation of symmetrical CVC syllables

Abstract

Previous studies have shown that the discriminability of a pair of stop consonants is determined by the particular consonant pair and by its position in a CVC syllable. The hypothesis that these differences in discriminability are related to differences in the auditory representations of the stimuli, following frequency analysis by the peripheral auditory system, was tested in two experiments. First, the discriminability of each pair of consonants from the set, and synthesised with noise excitation and without release bursts, was estimated from the confusions made by seven normal-hearing listeners in an identification task. Second, the auditory representation of each consonant in the syllable-initial and syllable-final position was measured by means of a simultaneous-masking technique. Two cues to a consonant's identity are (a) the instantaneous spectrum at the onset (syllable initial)_or offset (syllable final) of the formant transition, and (b) the formant transition pattern. The discriminability of six pairs of consonants (three initial and three final) was correlated with both the difference between their masking patterns at onset or offset ( ϱ −0.89) and with the difference between their auditory transition patterns ( ϱ= 0.94). The strength of these correlations indicates that the variations in consonant discriminability which have been reported may be predictable from a knowledge of their auditory representations at a peripheral level, with relatively little contribution from phonetic, linguistic, or cognitive factors.