Asymmetry relations between laterality IQ memory and management of dominant hemispheres in twins

Abstract

Lateral preferences in humans may be a key to many important topics in biology and physiology. However little is known about genetic and environmental factors for lateral preference. Comparisons of monozygotic (MZ) and dizygotic (DZ) twins can indicate which characters are hereditary or environmental. The aim of this study is to investigate morphological, functional and cognitive lateralities in twins in terms of hereditary and environmental factors. For this aim the handedness and body laterality (motor), IQ (mental), Hemispheric dominance (cognitive) and morphological properties such as head diameter hand and foot dimensions (anatomical) were measured to determine asymmetry traits on 100 MZ, 92 DZ twin pairs. As compared with DZ twins the correlations among the studied traits (IQ, visual memory, anatomical features, brain lateralization and handedness) were found higher in MZ twins.

Key words:Handedness, IQ, laterality, dominant hemispheres,twins.

Keywords

• Handedness, IQ, laterality, dominant hemispheres, twins

Kaynakça

1. Geschwind N, Behan P. Left-handedness: association with immune disease, migraine, and developmental learning disorder. Proc Natl Acad Sci U S A 1982; 79: 5097-100.
2. Su CH, Kuo PH, Lin CC, Chen WJ. A school-based twin study of handedness among adolescents in Taiwan. Behav Genet 2005; 35: 723-33.
3. Vuoksimaa E, Koskenvuo M, Rose RJ, Kaprio J. Origins of handedness: a nationwide study of 30161 adults. Neuropsychologia 2009; 47: 1294-1301.
4. Galton, F. The history of twins, as a criterion of the relative powers of nature and nurture. J. Anthropol. Inst 1875; 12: 566-576.
5. Reiss M, Tymnik G, Kögler P, Kögler W, Reiss G. Laterality of hand, foot, eye, and ear in twins. Laterality 1999; 4: 287-297.
6. Bishop DVM. Handedness and specific language impairment: A study of 6‐year‐old twins. Developmental psychobiology 2005; 46: 362-369.
7. Rosch RE, Ronan L, Cherkas L, Gurd JM. Cerebellar asymmetry in a pair of monozygotic handedness‐discordant twins. Journal of anatomy 2010; 217: 38-47.
8. Suzuki K, Ando J. Genetic and environmental structure of individual differences in hand, foot, and ear preferences: A twin study. Laterality Asymmetries of Body Brain and Cognition 2014; 19: 113-128.

9. Segal NL. Origins and imlications of handedness and relative birth weight for IQ in MZ twin pairs. Neuropsychol 1989; 27: 549-561.
10. Oldfield RC. The assessment and analysis of handedness: the Edinburgh inventory. Neuropsychologia 1971; 9: 97-113.
11. Yetkin Y. The examination of preferences related to using of right or left hand, foot and eye. Trends J Med Sci 1993; 19: 133-142.
12. Tan Ü. The distribution of hand preference in normal men and women. International Journal of Neuroscience 1988; 41: 35-55.
13. Cattell RB. A culture-free intelligence test. I. Journal of Educational Psychology 1940; 31: 161.
14. Alder H. The Right Brain Manager: How to Use the Power of Your Mind to Achieve Personal and Professional Success (2nd ed). London: Piatkus Books, 1999.
15. Fraga MF, Ballestar E, Paz MF, et al. Epigenetic differences arise during the lifetime of monozygotic twins. Proceedings of the National Academy of Sciences of the United States of America 2005; 102: 10604-10609.
16. Ellis SJ, Ellis PJ, Marshall E. Hand preference in a normal population. Cortex 1988; 24:157-163.
17. Shimizu A, Endo M. Comparison of patterns of handedness between twins and singletons in Japan. Cortex 1983; 19: 345-352.
18. Sicotte NL, Woods RP, Mazziotta JC. Handedness in twins: a meta-analysis. Laterality Asymmetries of Body Brain and Cognition 1999; 4: 265-286.
19. Kıylık B. The relationship between the right hemisphere management and the dominance of the left hemisphere in right-and left handers. Yuzuncu Yıl University, Healthy Sciences Institute, MA Thesis in Department of Physiology, Van, Turkey, 2005.
20. Ronalds GA, De Stavola BL, Leon DA. The cognitive cost of being a twin: evidence from comparisons within families in the Aberdeen children of the 1950s cohort study. BMJ 2005; 331:1306.
21. Posthuma D, De Geus EJ, Bleichrodt N, Boomsma DI. Twin–singleton differences in intelligence? Twin Research 2000; 3: 83-87.