THE STRUCTURE OF PHENOTYPICAL VARIABILITY IN READINESS POTENTIAL IN 6-7 YEARS OLD CHILDREN

This report is a part of a larger project, the major purpose of which is a longitudianal study of developmental changes in genetic control of variation in Bereitshaft potentials (BP). 15 pairs of MZ and 15 pairs of DZ twins aged 6-7 years participated in the BP study. 2 second epochs of EEC time-locked to the movement were digitized off-line at 500 Hz (DAS-16G <<Metrabyte>>), for 1500 msec, prior to and 5000 msec after movement. A complex BP waveform with the positive components was discovered in young children. We fitted four basic models to the twin data for each of the BP in F3, G4, C3, C4. Since the models (V(A), E(W)) in F3, F4, C3 and (E(B), E(W)) in C4 fit very well and cannot be improved markedly by adding the most important alternative parameters, we conclude that variation of BP of F3, F4, C3 is best explained by a very simple genetic model, and variation of BP of C4 is best explained by a simple environmentsl model.