Production and perception of syllable stress by children with normal hearing and children with hearing impairment

The production and perception of syllable stress by 15 children with a severe or profound hearing impairment were compared to those of 15 children with normal hearing of the same ages (10-13 years). The children were recorded while reading 10 Hebrew bisyllabic minimal pairs differing only in their stress pattern. The children's productions were evaluated acoustically and perceptually. Also evaluated were children's stress perceptions of an adult speaker's recordings of the same minimal pairs. The production results showed that, in general, the fundamental frequency (F0) was higher and the duration of syllables was longer across stressed and unstressed syllables spoken by the children with hearing loss compared to those of the children with normal hearing. The relative intensity was equal for the two groups. Both groups of children produced stress (which was correctly perceived) similarly; they produced higher F0, longer duration, and more intensity in the stressed syllable compared to the unstressed syllable. However, some children with hearing loss were less successful in conveying the stress information, demonstrating individual differences in using acoustic parameters for stress production. Those productions that were incorrectly perceived were characterized by unstressed syllables with a higher F0 and greater amplitude compared with the stressed syllables. With respect to stress perception, the children with hearing loss achieved a score of 80.3% compared with a 100% score by the children with normal hearing. Perception and production correlations were examined. Significant correlations were found between stress production and perception, and between stress perception and residual hearing in the children with hearing loss. Similarities/differences between findings for these Hebrew stimuli and previous findings for English stimuli are discussed.