Relationship between Perceptual Ability and the Effects of
Perturbations on Produced Vowel Contrasts

J Perkell, M Matthies, F Guenther, H Lane, E Stockmann, M Tiede, M Zandipour


This experiment explores the interaction between articulatory and auditory perturbation on the one hand, and a speakerís perceptual acuity on the other, in determining the vowel contrasts he or she produces. We recorded the acoustic signal for clear-speech productions of heed, hid, head, had and hod from six subjects under four conditions: no perturbation, bite block, masking noise, and both bite block and masking noise.A measure of overall vowel contrast, AVS (average spacing in the F1, F2 plane among all vowel pairs) tended to decrease with increasing amounts of perturbation, but speakers varied in this respect. Values of AVS reduction under perturbation with the bite block plus masking noise were strongly related to the speakerís vowel discrimination scores (mean peak ABX percent correct, determined in a prior study; r = .95; p < .01). We are analyzing data from five additional subjects to determine if this relation is supported within the larger group of 11 subjects, and to explore the separate and interacting effects of the auditory and articulatory perturbations.