Clinical Research Directory

Inclusion Criteria: Because clinical precision is required, 4- to 8-year-olds will complete a large test battery. * All children (TD, DLD, DLD + SSD, SSD) will score above 75 on the Nonverbal Scale of the Kaufman Assessment Battery for Children (KABC-II), which is above the Diagnostic and Statistical Manual cut-off for intellectual disability, even considering the standard error of measurement. * Hearing will be within normal limits * Oral structures will be within normal limits (Robbins \& Klee, 1987). * The Childhood Autism Rating Scale (Schopler et al., 2010) and parent report, will be used to rule out autism. Children with DLD will meet standard criteria. * Children with DLD will score below the cutoff of 87 on the Structured Photographic Expressive Language Test-P2 (SPELT-P2; Dawson et al., 2005) that has demonstrated high diagnostic accuracy for DLD. * Children with DLD will perform below 80% in their spontaneous production of finite verb morphemes. * Performance on a nonword repetition task will also support DLD status. Scores below 70% for total phonemes correct across all nonword lengths are greater than 1 SD below the mean for typical children. * Speech production skills will be measured via the Goldman-Fristoe Test of Articulation-3 (GFTA-3; Goldman \& Fristoe, 2015) and the inconsistency subtest of the Diagnostic Evaluation of Articulation and Phonology (DEAP, Dodd, et al., 2006). Many 4- to 6-year-old children with DLD are expected to perform below expected levels on the GFTA-3; for this study half of the children with DLD will show performance below expected levels and half above a standard score of 85. Children with SSD will show impaired performance on the GFTA-3, but typical performance on grammatically weighted language measures (SPELT-P2 and finite verb morphemes). The DEAP serves as a standardized measure of segmental inconsistency and will provide a post hoc analysis that may be related to sequence pattern variability. Performance on the following measures will serve as covariates and will not be exclusionary for DLD or SSD: * Peabody Picture Vocabulary Test, 4th ed (Dunn \& Dunn, 1997) * Expressive Vocabulary Test, 2nd ed (Williams, 1997) * Verbal and nonverbal memory span. * Because of the emphasis on English phonological and morpho-syntactic patterns, all participants will be monolingual English learners or report dominant exposure to English from infancy. Exposure to other languages will be documented. Exclusion Criteria for all participants: * Hearing impairment * Intellectual impairment * Autism * Significant motor impairment. Typical participants will be excluded if they show: -Histories of developmental, speech, language, or hearing disorders.