New study seeks to unlock the secrets of language learning in kids

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

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.