The within-pair EEG similarity of twins reared apart

  • H. H. Stassen
  • D. T. Lykken
  • G. Bombent


Within the broader context of our investigations into the heredity of the human EEG, we analysed the EEGs of 28 pairs of monozygotic and 21 pairs of dizygotic twins who were separated as infants and reared apart. The principal goal of this study was to determine the degree to which environmental factors possibly influence the development of a person's EEG. Monozygotic twins reared apart were, with respect to their EEGs, only slightly less similar to each other (if there is any difference at all) than the same person is to himself over time. For dizygotic twins reared apart, we verified the findings of our previous study, namely, that the average within-pair similarity of EEGs estimated from a sufficiently representative sample of fraternal twins was significantly higher than the average inter-individual similarity of EEGs obtained from unrelated persons. The results on both monozygotic and dizygotic twins, yielded conclusive proof that the individual EEG pattern is predominantly determined by hereditary factors.

Key words

EEG Genetics MZ/DZ twins reared apart Within-pair similarity 


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Copyright information

© Springer-Verlag 1988

Authors and Affiliations

  • H. H. Stassen
    • 1
  • D. T. Lykken
    • 2
  • G. Bombent
    • 1
  1. 1.Research DepartmentPsychiatric University Hospital ZurichZurichSwitzerland
  2. 2.Department of PsychiatryUniversity of MinnesotaMinneapolisUSA

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