Acoustic variation among African American and European American children: Age, gender, and ethnicity

Abstract

Previous research has shown vowels are acoustically specified based on their formant frequencies (Peterson & Barney, 1952). Hillenbrand et al. (1995) replicated and extended this study. While both studies included children, neither included variation across children’s gender or ethnicity. The present study explores variations in phonemic production for children across age, gender, and ethnicity. Children were presented with a list of /h-vowel-d/ words and sentences (“I hear the sound of /h-V-d/ some more”) containing 12 General American English vowels (/i,ɪ,e,ɛ,æ,ʌ,ɑ,ɔ,o,ʊ,u,ɝ/). Height and weight were also measured. We hypothesize that fundamental and formant frequencies will be higher for 8 to 9 year olds than for 10 to 12 year olds and higher for girls (by age 10). For ethnicity, we anticipate no significant differences in frequency measures between European-American and African-American children. This study contributes to our knowledge of developmental trajectories for specified acoustic parameters. As gender and ethnicity are vital cues for adult speakers, it is important to investigate how salient acoustic parameters are for child speakers and at what ages child parameters begin to approximate adult measures. Results will have implications for audiologists, speech language pathologists, developmental scientists, and others in the field of communication sciences and disorders.