Effect of Complexity on Speech Sound Development: Evidence From Meta-Analysis Review of Treatment-Based Studies

In the current study, we aimed at understanding the effect of exposure to complex input on speech sound development, by conducting a systematic meta-analysis review of the existing treatment-based studies employing complex input in children with speech sound disorders. In the meta-analysis review, using a list of inclusion criteria, we narrowed 280 studies down to 12 studies. Data from these studies were extracted to calculate effect sizes that were plotted as forest plots to determine the efficacy of complexity-based treatment approaches. The outcome variables of interest were improvement on the treated and generalization to the untreated sounds. Meta-analysis revealed that the exposure to complex input not only promoted improvement in production of complex speech sounds (d = 1.08, CI = 0.98–1.19) but also facilitated the production of untreated simple speech sounds (d = 2.69, CI = 1.98–3.54). Overall, the current findings revealed that the exposure to complex input promotes acquisition of both complex and simple speech sounds. The current findings are in line with the models of language learnability. The current findings have implications in the treatment of speech sound disorders.

The Oxford Handbook of Developmental Linguistics

This handbook provides a thorough and systematic investigation of the question of how we come to know a language. Researchers from all over the world explore the leading research questions within developmental linguistics, which include: What does the newborn child bring to the task of language acquisition? What information must the child extract from her linguistic input? And how does biological maturation interact with the child’s developing linguistic abilities? In the main body of the handbook, each chapter addresses a single area of grammatical knowledge, such as syllable structure, negation, or binding theory, and begins with an overview of the fundamental generalizations that guide current linguistic analyses and the features of grammatical representation that these generalizations entail. This is followed by a consideration of language learnability; a review of the relevant acquisition literature organized according to target language, age range of the child, and research methodology; and, finally, a discussion of a series of broader questions, such as: Do the experimental findings that were reviewed in the chapter favour a particular approach to the logical problem of language learnability? In what ways, if any, does the child’s knowledge surpass the information directly available from the input? In what ways can innate structure make the input more informative? Likewise, are there ways in which the child’s knowledge seems more limited than expected, given the richness of the available input?