with the combined age cohorts, our sample was small by current standards (although not by the standards in place when we began this investigation). In addition, to the degree that dominance effects influence these EEG parameters, we will have overestimated the magnitude of additive genetic influence in our biometric model-fitting analyses (i.e., the narrow sense heritability of each endophenotype). However, the evidence for such effects in ADE twin models was extremely weak.
