Applied Psycholinguistics

Articles

The language phenotype of a small geographically isolated Russian-speaking population: Implications for genetic and clinical studies of developmental language disorder

NATALIA RAKHLINa1, SERGEY A. KORNILOVa2, DEAN PALEJEVa3, ROMAN A. KOPOSOVa4, JOSEPH T. CHANGa5 and ELENA L. GRIGORENKOa6 c1

a1 Yale University

a2 Yale University, University of Connecticut, Haskins Laboratories, and Moscow State University

a3 Yale University

a4 University of Tromsø and Northern State Medical University, Arkhangelsk

a5 Yale University

a6 Yale University, Haskins Laboratories, Moscow State University, and Columbia University

ABSTRACT

This article describes the results of an epidemiological study of developmental language disorder (DLD) in an isolated rural Russian population. We report an atypically high prevalence of DLD across all age groups when contrasted with a comparison population. The results are corroborated by a set of comparisons of school-aged children from the target population with their age peers and mean length of utterance matches from the comparison population. We also investigate the relationship between nonverbal cognition, verbal working memory, and expressive language performance in the population, and find statistically significant but small effect sizes. Finally, we describe the complex and heterogeneous structure of the phenotype in the population along with patterns of its vertical transmission on the basis of the exemplar pedigrees, and discuss the implications of our findings for genetic and clinical studies of DLD.

(Received December 26 2010)

(Accepted August 05 2011)

Correspondence

c1 ADDRESS FOR CORRESPONDENCE Elena L. Grigorenko, Child Study Center, 230 South Frontage Road, Yale University, New Haven, CT 06519-1124. E-mail: elena.grigorenko@yale.edu

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