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Are Differences between Twins a Result of Mutual Rivalry?

Published online by Cambridge University Press:  01 August 2014

J. G. Borg*
Affiliation:
Department of Psychology, University of Tampere, Finland
*
University of Tampere, Department of Psychology, P.O. Box 607, SF-33101 Tampere 10, Finland

Abstract

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The sexual index included in the Szondi test makes it possible to define the domains of an individuals “internal sex” or gender – especially the degree of the subject's bisexuality. This index was employed in a comparison between partners reared together in 62 monozygotic and 23 dizygotic pairs of twins. The observed incongruence in 1/3 MZ pairs would not appear to derive totally from errors of measurement. In most of these pairs it is competition which underlies the incongruence seen on the sexual index. It was further observed that the congruence here as in general in female pairs is clearly more marked than in males. A hypothesis was proposed, whereby competition for dominance is a distinctively major-tonality (masculinity) characteristic. The incongruence is more conspicuous among males because males are in general more markedly major-toned than females. This hypothesis was borne out. It is thus necessary here as in general to adopt two sex variables in parallel: external (i.e. matricular) sex and internal sex (gender). It is due to the presence of these competitive pairs that the means and especially deviations of twins' test results will consistently diverge from those in the population at large.

Type
Research Article
Copyright
Copyright © The International Society for Twin Studies 1997

References

REFERENCES

1.Bem, SL (1974): The Measurement of Psychological Androgyny. Consulting and Clinical Psychology. 42 (2): 155162.Google Scholar
2.Borg, JG (1988): Farben, Affekte und Szondi-Triebe. Eine systemtheoretische Integration. Acta Univ Tamperensis. Ser A, Vol. 244.Google Scholar
3.Borg, JG (1993a): Überprüfung des Szondi-Tests (Teil I). Ermittlungen des Sexualindexes anhand von Zwillinguntersuchungen. Szondiana 1.Google Scholar
4.Borg, JG (1993b): Überprüfung des Szondi-Tests (Teil II). Überprüfung der Arbeitsteilungshypothese bei eineiigen Zwillingen. Szondiana 2.Google Scholar
5.Borg, JG (1993c): Dur-Eigenschaften und Extraversion. Szondi-Kongress, Budapest, 16.4.1993. Unpublished.Google Scholar
6.Borg, JG (1994/1992): Überprüfung des Szondi-Tests (Teil III). Die Differenzierung von Zwillingen – ein Produkt von internen Konkurrenz? Szondiana 2.Google Scholar
7.Carey, G (1986): Sibling imitation and contrast effects. Behaviour Genetics 16: 319342.Google Scholar
8.Carli, LL (1989): Gender differences in interaction style and influences. Journal of Personality and Social Psychology 56: 565576.Google Scholar
9.Cattell, RBet al. (1970): Handbook for the sixteen personality factor questionnare (16PF). Champaign: Institute for Personality and Ability Testing.Google Scholar
10.Cesarec, Z, Marke, S (1964): CMPS: Cesarec-Marke Personlighetsschema. Lund. (Psykologien kustannus OY. Helsinki 1978).Google Scholar
11.Dalgard, OS, Kringlen, EA (1976): A Norwegian twin study of criminality. British Journal of Criminology 16: 213232.CrossRefGoogle Scholar
12.Deri, S (1949): Introduction to the Szondi Test. New York Stratton. New edition in french: Melon J (1991). Introduction au test de Szondi. Bryssel: De Boek-University.Google Scholar
13.Eaves, L, Young, PA (1981): Genetical theory and personality differences. In Lynn, R (ed.), Dimensions of personality; papers in honour of H J Eysenck, pp. 129179.Google Scholar
14.Eaves, LJ (1987). Dominance is not enough. Behaviour Genetics 8: 2733.Google Scholar
15.Eaves, LJ, Eysenck, HJ, Martin, NG (1989): Genes, culture and personality. London: Academic Press.Google Scholar
16.Eysenck, HJ and Eysenck, SBG (1975): Manual of the Eysenck Personality Questionnaire. Hodder & Stoughton. London.Google Scholar
17.Eysenck, Sybil BG and Haapasalo, Jaanna (1989): Cross-cultural comparisons of personality: Finland and England. Person Individ Diff 10: 121125.CrossRefGoogle Scholar
18.Farber, SL (1981): Identical twins reared apart, a reanalysis. New York: Basic Books, Inc., Publishers.Google Scholar
19.Foch, TT, Plomin, R (1980): Specific Cognitive Abilities in 5 – to 12 – Year-Old Twins. Behaviour Genetics 10 (6): 507520.Google Scholar
20.Freimuth, MJ, Hornstein, GA (1982): A Critical Examination of the Concept of Gender. Sex Roles 8: 515532.Google Scholar
21.Gregory, RL (1966): Eye and brain. London, Weidenfeld & Nicolson.Google Scholar
22.Hay, DA, O'Brien, PJ (1984): The Role of Parental Attitudes in the Development of Temperament in Twins at Home, School and in Test Situations. Acta Genet Med Gemellol 33: 191204.Google ScholarPubMed
23.Hildén-Jokela, S (1996): Sosiaalinen sukupuoli BSRI– ja Szondi– testillä mitattuna sekä sosi-aalisen sukupuolen yhteys psyykkiseen terveyteen. Pro-Gradu-Study, University of Tampere.Google Scholar
24.Kaprio, J, Sarna, S, Koskenvuo, M, Rantasalo, I (1978): Finnish twin registry: Formation and compilation, questionnaire study, zygosity determination procedures and research program. Prog Clin Biol Res 24B: 179184.Google Scholar
25.Langinvainio, H, Kaprio, J, Koskenvuo, M, Lönnqvist, J (1984): Finnish Twins Reared Apart III: Personality Factors. Acta Genet Med Gemellol 33: 259264.Google ScholarPubMed
26.Leinonen, P (1994): Identtisten kaksosten persoonallisuuden, erityisesti sisäisen sukupuolen yhdenmukaisuus. Pro-Gradu-Study, University of Tampere.Google Scholar
27.Maccoby, EE (1990): Gender and relationship. American Psychologist 45: 513–250.CrossRefGoogle Scholar
28.Mackinnon, AJ, Henderson, AS, Andrews, G (1991): The Parental Bonding Instrument: a measure of perceived or actual parental behaviour? Acta Psychiatr Scand 83: 153159.Google Scholar
29.Martin, N, Jardine, R (1986): Eysenck's contributions to Behavior Genetics. In Modgil, S, Modgil, C (ed.), Hans Eysenck: Consensus and Controversy, Philadelphia and London: The Falmer Press: 1347.Google Scholar
30.McCartney, K, Harris, MJ & Bernieri, F (1990): Growing up and growing apart: a developmental meta-analysis of twin studies. Psychological Bulletin. 107 (2): 226237.Google Scholar
31.Moilanen, I (1987): Dominance and submissiveness between twins. Perinatal and developmental aspects. Acta Genet Med Gemellol 36: 249255.Google Scholar
32.Mäkinen, R (1968): Sosiaalisen ja impulsiivisen ekstraversion mittaaminen EPI – lomakkeella – Uusi kyselylomake EPI-C (NESI). Reports fro the Department of Psychology, University of Jyväskylä. Finland, No. 78.Google Scholar
33.O'Brien, PJ, Hay, DA (1987): Birthweight Differences, the Transfusion Syndrome and the Cognitive Development of Monozygotic Twins. Acta Genet Med Gemellol 36: 181196.Google Scholar
34.Rose, RJ, Kaprio, J (1988): Frequency of Social Contact and Intrapair Resemblance of Adult Monozygotic Cotwins – Or Does Shared Experience Influence Personality After All? Behavior Genetics 18 (3): 309328.CrossRefGoogle Scholar
35.Rose, RJ, Koskenvuo, M, Kaprio, J, Sarna, S, and Langinvainio, H (1988): Shared genes, shared experiences and similarity of personality: Data from 14, 288 adult Finnish twins. J Person Soc Psychol 54: 161171.Google Scholar
36.Szondi, L (1956): Ich-Analyse. Bern: Hubver.Google Scholar
37.Szondi, L (1960): Lehrbuch der experimentellen Triebdiagnostik. Textband 2. Aufl Bern: Huber (1947: Experimentelle Triebdiagnostik).Google Scholar
38.Schave, B, Ciriello, J (1983): Identity and intimacy in twins. New York: Praeger Publishers.Google Scholar
39.Tienari, P (1963): Psychiatric illness in identical twins. Acta psychiat scand suppl 171: 39.Google Scholar
40.Vogel, F, Motulsky, AG (1986): Human Genetics 2nd edition. Berlin & Heidelberg: Springer-Verlag.Google Scholar