Ipsen, Melannee; Allen, Audrey; Urness, Katherine; Thacker, Melinda; Cabbage, Kathryn (Brigham Young University)
Faculty Advisor: Cabbage, Kathryn (McKay School of Education, Communication Disorders)
Speech delays affect up to 12% of children and are the most common communication disorder treated by speech-language pathologists (Lewis et al., 2006). Furthermore, approximately 18% of preschool-aged children with speech delay will develop dyslexia or other reading impairments (Lewis et al., 2011).
Current research agrees that both children with SD and those with dyslexia have deficits in phonology---the underlying system responsible for processing and organizing speech sounds (Anthony et al., 2011; Snowling, 2000). Both children with SD and children with dyslexia have specific deficits in speech perception (Lof & Synan, 1997; Rosen, 2003). It is unclear the degree to which these groups differ in underlying aspects of phonology, such as speech perception. Prior research suggests that these children may display distinct speech perception patterns based on their SD or dyslexia status (Cabbage, Hogan, and Carrell, 2016; Johnson et al., 2011). Speech components that cause speech perception difficulties for children with SD may be different from those that cause difficulty for those with dyslexia. Specifically, children with SD have been shown to have more difficulty perceiving the rapid temporal aspects, or spectral structure, of speech (e.g., formant frequency transitions) while those with dyslexia have been shown to have more difficulties perceiving the more global structure of speech (e.g., amplitude envelopes, syllabic cues) (Cabbage, et al., 2016; Goswami, 2011; Johnson et al., 2011).
The current study compares speech perception abilities in children with SD, children with SD+dyslexia, and typical peers in speech modified in spectral and global acoustic structure. We expect children with SD or SD+dyslexia will show poorer perception for spectral speech tasks and only children with SD+dyslexia will show poorer perception for global speech tasks. These findings will be used to help detect which children with SDs are at a higher risk for developing dyslexia.