SPEECH PERCEPTION AND AUDITORY ABILITIES IN INFANTS, CHILDREN, AND ADULTS WITH DOWN SYNDROME - ABSTRACT OF FUNDED PARENT AWARD (1R01DC020229)
(NO CHANGE)
The goal of this project is to characterize the speech perception and auditory abilities of infants, children,
and adults with Down syndrome. Prior research involving individuals who are neurotypical has highlighted the
importance of early perceptual development on long-term speech and language outcomes, but little is currently
known about the factors that support communication outcomes for individuals with Down syndrome. We do know
that the development of functional hearing skills in children who are neurotypical (such as understanding speech
when several people are talking at the same time) requires years of experience with sound, extensive language
knowledge, and maturation of executive function. These observations suggest that attainment of speech
perception and hearing milestones is likely to be delayed or disrupted for children with Down syndrome, due to
limitations in intellectual functioning, language knowledge, and cognitive processing. The first aim of this project
evaluates phoneme perception in infants, children, and adults with Down syndrome, with a focus on
characterizing infants’ discrimination of native and non-native speech contrasts and examining effects of hearing
loss on the consonant identification in children and adults. The second aim tests the hypothesis that maturation
of selective listening strategies follows a delayed time course of development for individuals with Down
syndrome, resulting in greater susceptibility to interference from competing background sounds. The third aim
characterizes the ability to recognize speech in the presence of competing background sounds in children and
adults with Down syndrome, accounting for individual differences in factors such as linguistic knowledge and
working memory. The results generated by this project are expected to inform theoretical models regarding the
development of speech perception and hearing abilities in individuals with Down syndrome, and have the
potential to provide preliminary guidance for strategies to maximize speech communication outcomes in noisy
environments such as classrooms.
