Graduation Year


Document Type




Degree Granting Department

Communication Sciences and Disorders

Major Professor

Ruth H. Bahr, Ph.D.

Committee Member

Nathan Maxfield, Ph.D

Committee Member

Jean Krause, Ph.D


Categorical perception, African American English, phonological processing, literacy development, final consonant devoicing


Children at risk for reading problems also have difficulty perceiving critical

differences in speech sounds (Breier et al., 2004; Edwards, Fox, & Rogers, 2003; de-

Gelder & Vroomen, 1998). These children rely more heavily on context than the acoustic

qualities of sound to facilitate word reading. Dialect use, such as African American

English (AAE) may influence literacy development in similar ways. Dialect use has been

shown to affect speech sound processing and can even result in spelling errors (Kohler, et

al., in press). The purpose of this study is to determine if children who speak AAE

process cues indicative of final consonant voicing differently than children who speak a

more mainstream dialect of English.

Twenty-six typically developing children in grades K-2 who spoke either AAE or

a more mainstream American English dialect participated. The speech stimuli consisted

of nonsense productions of vowel + plosive consonant. These stimuli were systematically

altered by changing the vowel and stop-gap closure duration simultaneously, which

resulted in the final consonant changing from a voiced consonant, like “ib”, to a voiceless

consonant, like “ip”. Two tasks were developed: a continuum task where the child had to

indicate when the stimuli changed in voicing and a same-different task which involved

determining if two stimuli were identical in voicing or not.

No significant differences between groups were found for dialect use or grade for

the same/different task. In the continuum task, chi-square analyses revealed significant

differences in response patterns attributable to dialect and grade. In addition, a significant

consonant by speaker interaction was found for mean ratings. Correlations between mean

continuum rating and phonological awareness composites were not significant.

In conclusion, it was evident that children who speak AAE present with

differences in their perception of final consonants in VC nonsense syllables. This finding

suggests the dialect speakers may be using different cues to make judgments regarding

the speech signal, or that the speakers of AAE have a less mature ability to extract fine

phonetic detail due to the influence of their dialect (Baran & Seymour, 1979). More

research is warranted to determine the exact role that dialect plays.