i
Shared Etiology of Phonological Memory and Vocabulary Deficits in School-Age Children
-
Dec 28 2012
Source: J Speech Lang Hear Res. 56(4):1249-1259
Details:
-
Alternative Title:J Speech Lang Hear Res
-
Personal Author:
-
Description:Purpose
The goal of this study was to investigate the etiologic basis for the association between deficits in phonological memory (PM) and vocabulary in school-age children.
Method
Children with deficits in PM or vocabulary were identified within the International Longitudinal Twin Study (ILTS). The ILTS includes 1,045 twin pairs from the United States, Australia, and Scandinavia aged 5 to 8 years. We applied the DeFries-Fulker regression method to determine whether problems in PM and vocabulary tend to co-occur because of overlapping genes, overlapping environmental risk factors, or both.
Results
Among children with isolated PM deficits, we found significant bivariate heritability of PM and vocabulary weaknesses both within and across time. However, when probands were selected for a vocabulary deficit, there was no evidence for bivariate heritability. In this case, the PM-vocabulary relationship appeared to owe to common shared environmental experiences.
Conclusions
The findings are consistent with previous research on the heritability of specific language impairment and suggest that there are etiologic subgroups of children with poor vocabulary for different reasons, one more influenced by genes and another more influenced by environment.
-
Subject:
-
Pubmed ID:23275423
-
Pubmed Central ID:PMC3615120
-
Document Type:
-
Funding:
-
Place as Subject:
-
Collection(s):
-
Main Document Checksum:
-
Download URL:
-
File Type: