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Arnold School of Public Health

Child Language Research Group


Since 1983, members of the Child Language Research Group have actively pursued a scientific agenda designed to evaluate the effects of services to young children with impaired communication systems. During this period, faculty and student-initiated research have covered a wide range of topics, including parent-child interactions, phonologic generalization, factors contributing to word learning and lexical access, and the impact of early speech delays on later language development and overall academic performance. The results of these studies have shaped a specific program of research that now involves collaborative and interdisciplinary inquiry into emerging literacy in preschoolers and the efficacy of early intervention approaches and their long-term effects on learning.

The clinically-based programs at the USC Speech and Hearing Research Center, coupled with cooperative arrangements with various public schools, Head Start programs, and community clinics, have provided a participant base to sustain this research agenda. Supported, in part, by 19 years of federal funding, the Center’s specialty clinics, which together comprise the USC Early Language Programs, include the Early Language Preschool, Parent Program, Child Phonology Clinic, and Pediatric Language Groups.


Group Members

Suzanne M. Adlof is an assistant professor in the Department of Communication Sciences and Disorders and the Director of the SCROLL Lab (South Carolina Research on Language and Literacy). She received her bachelor’s degree from the University of Central Arkansas and her master’s and doctoral degrees from the University of Kansas. She then completed a post-doctoral fellowship at the University of Pittsburgh. Her research examines developmental relationships between oral and written language development and disorders (e.g., SLI, dyslexia, poor reading comprehension), with the overarching goals of improving the early identification of at-risk children and developing effective treatments to improve academic outcomes.

Angela N. McLeod is an assistant clinical professor in the Department of Communication Sciences and Disorders. She attended undergraduate school at Clemson University (BA 1991, BS 1992) and received her master’s degree in speech-language pathology from Appalachian State University in 1994. Angela completed her doctoral studies at the University of South Carolina in 2004. Her current research investigates the relationship between storybook reading and fast mapping in young children. Other research interests include 1) emergent literacy and 2) language development and disorders.

Allen A. Montgomery is a research professor in the Department of Communication Science and Disorders, Coordinator of the Ph.D. program (where he does the majority of his teaching), and Co-Director of the Language Processing Laboratory. He received his bachelor’s degree in mathematics and master’s degree in Speech Pathology (with Van Riper) at Western Michigan University. His PhD is in Speech Science from Purdue University. Al’s research interests include lexical access, word recognition, speech reading, and fluency.

Danielle R. Varnedoe is senior clinical instructor in the Department of Communication Sciences and Disorders and Director of the University of South Carolina Speech & Hearing Research Center.  She received her bachelor’s and master’s degree from the University of Akron. Danielle’s research interests involve 1) efficacy and generalization learning in treatment of speech sound disorders; 2) the effects of phonologic disorders on emerging literacy skills and 3) the relationship between parent involvement and therapy progress in the treatment of children with severe speech sound disorders.

Krystal Werfel is an assistant professor in the Department of Communication Sciences and Disorders and Director of the Written Language Lab.  She received her bachelor’s degree in Early Childhood Development from the University of Tennessee and her master’s (speech-language pathology) and doctorate (speech & hearing science) from Vanderbilt University.  Dr. Werfel’s research interests include written language development and disorders, emergent literacy development, specific language impairment, and hearing loss.

Selected Publications

Adlof, S.M., & Perfetti, C.A. (in press). Individual differences in word learning and reading ability. In A. Stone, B.Ehren, E. Silliman, & G. Wallach (Eds.). Handbook of Language and Literacy Development and Disorders, 2nd Edition. New York: Guilford.

Adlof, S.M., Catts, H.W., & Lee, J. (2010). Kindergarten predictors of second vs. eighth grade reading comprehension impairments. Journal of Learning Disabilities. 43, 332-345.

Adlof, S.M., Perfetti, C.A., & Catts, H.W. (2011). What research says about assessment and instruction for different types of readers. In J. Samuels & A. Farstrup (Eds). What Research Has to Say About Reading Instruction, Fourth Edition (pp. 186-235). Newark, DE: International Reading Association.

Apel, K. & Apel, L. (2011). Identifying intra-individual differences in students' written language abilities. Topics in Language Disorders, 31, 54-72.

Apel, K. (2010). Kindergarten children’s initial spoken and written word learning in a storybook context. Scientific Studies in Reading, 14, 5, 440-463.

Apel, K. (2011). Science is an attitude: A response to Kamhi. Language, Speech, and Hearing Services in Schools, 42, 65-68.

Apel, K. (2011). What is orthographic knowledge? Language, Speech, and Hearing Services in Schools, 42, 592-603.

Apel, K., & Diehm, E. (in press). Morphological awareness intervention with kindergarteners and first and second grade students from low SES homes: A small efficacy study. Journal of Learning Disabilities.

Apel, K., & Lawrence, J. (2011). Contributions of morphological awareness skills to word-level reading and spelling in first-grade children with and without speech sound disorder. Journal of Speech, Language, and Hearing Research, 54, 1312-1327.

Apel, K., Brimo, D., Diehm, E., & Apel, L. (2013). Morphological awareness intervention with kindergarteners and first and second grade students from low SES homes: A feasibility study. Language, Speech, and Hearing Services in Schools, 44, 161-173. DOI: 10.1044/0161-1461(2012/12-0042)

Apel, K., Brimo, D., Wilson-Fowler, E.B., Vortius, C., & Radach, R. (2013). Children develop initial orthographic knowledge during storybook reading. Scientific Studies of Reading, 17, 286-302. DOI: 10.1080/10888438.2012.692742

Apel, K., Diehm, E., & Apel, L. (2013). Using multiple measures of morphological awareness to assess its relation to reading. Topics in Language Disorders, 33, 42-56. Doi: 10.1097/TLD.0b013e318280f57b

Apel, K., Thomas-Tate, S., Wilson-Fowler, E.B., & Brimo, D. (2012). Acquisition of initial mental graphemic representations by children at risk for literacy development. Applied Psycholinguistics, 33, 2, 365-391.

Apel, K., Wilson-Fowler, E.B., Brimo, D., & Perrin, N.A. (2012). Metalinguistic contributions to reading and spelling in second and third grade students. Reading and Writing, 25, 1283-1305.

Catts, H.W., & Adlof, S.M. (2011). Phonological and other deficits associated with dyslexia. In S. Brady, D. Blaze, & A. Fowler (Eds.), Explaining individual differences in reading: Theory and evidence. New York, NY: Taylor & Frances.

Catts, H.W., & Kamhi, A.G., & Adlof, S.M. (2012). Causes of reading disabilities. In A.G. Kamhi & H.W. Catts (Eds.) Language and Reading Disabilities, Third Edition (pp.77-111). Boston: Allyn & Bacon.

Catts, H.W., & Kamhi, A.G., & Adlof, S.M. (2012). Defining reading disabilities and classifying subgroups of poor readers. In A.G. Kamhi & H.W. Catts (Eds.) Language and Reading Disabilities, Third Edition (pp.45-76). Boston: Allyn & Bacon.

Cheng, L., Li, M., Kirby, J. R., Qiang, H., & Wade-Woolley, L. (2010). English language immersion and students’ academic success in English, Chinese, and mathematics.Evaluation and Research in Education, 23, 151-169.

Goodman, I., Libenson, A. & Wade-Woolley, L. (2010). Sensitivity to linguistic stress, phonological awareness and early reading ability in preschoolers. Journal of Research in Reading, 33, 113-221.

Hall-Mills, S., & Apel, K. (2011). Differential effects of letter name spelling and text representation on early reading ability. Contemporary Issues in Communication Science and Disorders, 38, 97-108. DOI: 1092-5171/11/3802-0097

Hall-Mills, S., & Apel, K. (2013). Narrative and expository writing of adolescents with language-learning disabilities: A pilot study. Communication Disorders Quarterly, 34, 135-143. Doi: 10.1177/1525740112465001

Hornsby, B. W. Y., Werfel, K. L., Camarata, S., & Bess, F. H. (in press). Subjective fatigue in children with hearing loss: Some preliminary findings. American Journal of Audiology.

Jared, D.J., Cormier, P., Levy, B. A., & Wade-Woolley, L. (2011). Early predictors of biliteracy development in children in French Immersion: A four-year longitudinal study.Journal of Educational Psychology, 103, 119-139.

Jared, D.J., Cormier, P., Levy, B. A., & Wade-Woolley, L. (2012). Cross-language activation of phonology in young bilingual readers. Reading and Writing, 25, 1327-1343.

Jared, D.J., Cormier, P., Levy, B. A., & Wade-Woolley, L. (2013). Discrimination of English and French orthographic patterns by biliterate children. Journal of Experimental Child Psychology, 114, 469-488.

Kim, Y-S., Apel, K., & AlOtaiba, S. (in press). The relation of linguistic awareness and vocabulary to word reading and spelling for first grade students participating in Response to Intervention. Language, Speech, and Hearing Services in Schools.

Kirby, J. R., Ball, A., Geier, B. K., Parrila, R. & Wade-Woolley, L. (2011). The development of reading interest and its relation to reading ability. Journal of Research in Reading, 34, 264-280. doi: 10.1111/j.1467-9817.2010.01439.x.

Kirby, J. R., Deacon, S. H., Bowers, P. N., Izenberg, L., Wade-Woolley, L. & Parrila, R. (2012). Children’s morphological awareness and reading ability. Reading and Writing, 25, 389- 410.

Korrapati, A., Werfel, K. L., Barnett, Z. P., & Schuele, C. M. (2013). Visual attention to print in preschool children with and without hearing loss. Young Scientist, 3, 54-56.

Lemmon, R. & McDade, H. (2013). The effects of age and household income on the use of literate language features. Communication Disorders Quarterly, 34, 144-151.

Li, M., Kirby, J. R., Cheng, L., Wade-Woolley, L. & Qiang, H. (2012). Cognitive predictors of English reading achievement in Chinese English-immersion students. Reading Psychology, 33(4).

Masterson, J., & Apel, K. (2010). Linking characteristics discovered in spelling assessment to intervention goals and methods. Learning Disabilities Quarterly, 33, 3, 185-198.

Masterson, J.J., & Apel, K. (2010). The Spelling Sensitivity Score: Noting developmental changes in spelling knowledge. Assessment for Effective Intervention, 36(1), 35-45.

Masterson, J.J., & Apel, K. (in press). Monitoring progress in spelling improvement.Perspectives on Language Learning and Education.

McLeod, A. & McDade, H. (2011). Preschoolers’ incidental learning of novel words during storybook reading. Communication Disorders Quarterly, 32, 256-266.

Perfetti, C.A. & Adlof, S.M. (2012). Reading Comprehension: A conceptual framework from word meaning to text meaning. In J. Sabatini, E. Albro, & T. O’Reilly (Eds.)Measuring Up: Advances in How We Assess Reading Ability. (pp. 3-20). Lanham, MD: Rowman & Littlefield Education.

Perfetti, C.A., Stafura, J., & Adlof, S.M. (2013). Reading comprehension and reading comprehension problems: A word-to-text integration perspective. In Miller, B., L. Cutting, & P. McCardle (Eds.) Unraveling the Behavioral Neurobiological, and Genetic Components of Reading Comprehension. Baltimore: Paul Brookes Publishing.

Puranik, C., & Apel, K. (2010). Effect of assessment task and letter writing ability on preschool children’s spelling performance. Assessment for Effective Intervention, 36(1), 45-56.

Pyle, A., Wade-Woolley, L. & Hutchinson, N. L. (2011). “Just listen to us”: The Role of Teacher Empowerment in the Implementation of Responsiveness to Intervention. Alberta Journal of Educational Research, 57, 258-272.

Simon, C. G., Werfel, K. L., & Schuele, C. M. (2011). Vowel representation in the spelling of kindergarten children. Young Scientist, 1, 29-31.

Wade-Woolley, L. & Heggie, L. (2015). Implicit knowledge of word stress and derivational morphology guides skilled readers’ decoding of unfamiliar words. Scientific Studies of Reading, 19, 21-30.

Wade-Woolley, L. & Heggie, L. (in press). Linguistic stress and reading: More than phonological awareness. In J. Thomson & L. Jarmulowicz (Eds.) Linguistic Rhythm and Literacy. John Benjamins Publishers: New York.

Werfel, K. L., & Schuele, C. M. (2012). Segmentation and representation of consonant blends in kindergarten children’s spellings. Language, Speech, and Hearing Services in Schools, 43, 292-307.

Wolter, J.A, Self, T., & Apel, K. (2011). Initial mental graphemic representation acquisition and later literacy achievement in children with language impairment: A longitudinal study. Journal of Learning Disabilities, 44, 543-555.

Wolter, J.A., & Apel, K. (2010). Initial acquisition of mental graphemic representations in children with language impairment. Journal of Speech-Language-Hearing Research. 53, 179-195.

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