EEG spectra in twins: Evidence for a neglected mechanism of genetic determination

Abstract

Electroencephalographic (EEG) spectra obtained from monozygotic (MZ) twins show striking within-pair similarity, while spectra of dizygotic (DZ) twins are no more similar than those obtained from pairs of unrelated persons. At least one parameter of the EEG spectrum, the midfrequency of the alpha rhythm, is strongly correlated (.8) within pairs of MZ twins and yet its correlation within pairs of DZ twins is about zero. The frequency composition of the resting EEG may be an example of “emergenesis,” in which the phenotypic character is determined by the interaction of independently heritable traits and is substantially altered if any genotypic component is changed. Such emergenic traits would not reveal their genetic origin in the usual analysis of pedigrees. © 1982, Psychonomic Society, Inc.. All rights reserved.