Voicing contrasts in brazilian portuguese stop consonants and hearing loss: acoustic and perceptive analisys

Abstract

Speech contrasts production and perception are affected by hearing impairment once important acoustic cues can be distorted or unavailable due to hearing loss, resulting in difficulties related to articulation manner and place, and also to voicing contrast. The aim of this article was to extend the knowledge about perception and production of voicing contrast, studying two subjects with descending configuration and moderately severe hearing loss. The acoustic analysis included voice onset time (VOT) and duration of stop consonant. The corpus consisted of ten repetitions of two-syllable words initiated by one of the six stops of PB (/p/,/b/,/t/,/d/,/k/,/g/) inserted in a carrier phrase. One hundred and twenty subjects without auditory complaints acted as judges and evaluated the oral productions of both subjects performing identification tasks. Results showed high percentage of correct answers in both perception tasks. Acoustical analysis revealed that S1’s results are in accordance to literature, showing significant differences between minimal pairs contrasting by voicing. S2 results for duration measures also differ in accordance to voicing contrasts, showing longer duration for unvoiced stops. VOT’s values are positive for unvoiced stops but voiced stops showed discontinuities in voicing bar during closure duration or, in other words, the sonority bar measurement did not coincide with occlusion duration. Both subjects produce and perceive efficiently voicing contrasts, despite differences found in the acoustical analysis.