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Language Development in Young Twins: Biological, Genetic and Social Aspects

Published online by Cambridge University Press:  01 August 2014

Peter Mittler
Peter Mittler*
Affiliation:
Hester Adrian Research Centre, University of Manchester, Great Britain

Abstract

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The present study has confirmed previous evidence that young twins show a marked delay in language development. This delay averaged six months at the age of 48 months, compared to a control group of singletons; it was evenly reflected in all nine subtests of the Illinois Test of Psycholinguistic Abilities, and was shown equally in MZ and DZ twins. Biological variables such as birth weight, gestational age and reproductive complications were only weakly associated with language scores at four years. The twins were not significantly retarded on non-verbal tests of general intelligence, compared with population norms or with the singleton controls. Environmental factors, particularly social class and family size were strongly correlated with language scores, though the association was stronger in singletons than in twins. Middle class twins were relatively much more retarded in language development compared with middle class singletons than working class twins compared with working class singletons. Comparison of intra-class correlations between 28 MZ and 64 DZ pairs yielded a heritability index of 44% for the test as a whole, with considerable variations in h2over the nine subtests. Heritabilities were highest for tests sampling the visual motor channel, and lowest for tests on the auditory-vocal channel. In confirmation of this finding, an examination of the test profiles of the singleton controls suggested that social class differences were most marked on tests of the auditory-vocal channel. It is suggested that the latter are more susceptible to environmental variables.

Type
9. Science For Twins/Twins For Science
Information
Acta geneticae medicae et gemellologiae: twin research , Volume 25 , Issue 1 , January 1976 , pp. 359 - 365
Copyright
Copyright © The International Society for Twin Studies 1976

References

REFERENCES

Burt, C. 1966. The genetic determination of differences in intelligence: a study of monozygotic twins reared together and apart. Br. J. Psychol., 57: 137–153.CrossRefGoogle ScholarPubMed
Day, E. 1932. The development of language in twins. 1. A comparison of twins and single children. 2. The development of twins: their resemblances and differences. Child Dev., 3: 179–199, 298–316.Google Scholar
Erlenmeyer-Kimling, , Jarvik, L.F. 1963. Genetics and intelligence. Science, 142: 1477–1479.CrossRefGoogle ScholarPubMed
Falconer, D.S. 1960. Introduction to Quantitative Genetics. London and Edinburgh: Oliver and Boyd.Google Scholar
Greenald, G. 1972. Language facilitation in a pair of monozygotic twins. Unpublished dissertation, University of Manchester.Google Scholar
Jensen, A.R. 1967. Estimation of the limits of heritability of traits by comparison of monozygotic and dizygotic twins. Proc. Natl. Acad. Sci., 58: 149–156.CrossRefGoogle ScholarPubMed
Koch, H.L. 1966. Twins and Twin Relations. Chicago: Chicago University Press.Google Scholar
Luria, A.R., Yudovitch, F.I.a. 1959. Speech and the Development of Mental Processes in the Child. London: Staples.Google Scholar
McCarthy, J.J., Kirk, S.A. 1961. The Illinois Test of Psycholinguistic Abilities (Experimental Edn.) Urbana, Ill.: Institute for Research in Exceptional Children.Google Scholar
Mittler, P. 1969 a. Psycholinguistic skills in four year old twins and singletons. Unpublished Ph. D. thesis, University of London.Google Scholar
Mittler, P. 1969 b. Genetic aspects of psycholinguistic abilities. J. Child Psychol Psychiatry, 10: 165–176.CrossRefGoogle ScholarPubMed
Mittler, P. 1970. Biological and social aspects of language development in twins. Dev. Med. Child Neurol., 12: 741–757.CrossRefGoogle ScholarPubMed
Mittler, P. 1971. The Study of Twins. London: Penguin Education.Google Scholar
Osgood, C.E. 1957. A Behavioristic Analysis. In Osgood, C.E. (ed.): Contemporary Approaches to Cognition. Cambridge, Mass.: Harvard University Press.Google Scholar
Piaget, J. 1926. Language and Thought of the Child. London: Routledge and Kegan Paul.Google Scholar
Record, R., McKeown, T., Edwards, J.H. 1970. An investigation of the difference in measured intelligence between twins and singletons. Ann. Hum. Genet., 34: 11.CrossRefGoogle Scholar
Scottish Council for research in education 1953. Social Implications of the 1947 Scottish Mental Survey. London: University of London Press.Google Scholar
Zazzo, R. 1960. Les Jumeaux: le Couple et la Personne. Paris: Presses Universitaires de France.Google Scholar