[Effect of genotype on the relationship between parameters of intelligence and cognitive style]

The roles of genetic and environmental factors in regulating parameters of intelligence and cognitive style were studied. Monozygotic and dizygotic twins were tested three times, at the ages of 6, 7, and 10 years. The Wechsler Intelligence Test, Embedded Figures Test, and Matched Figures Fitting Test were used. Interrelations between the Intelligence Quotient and cognitive style appeared to be Independent of the shared regulatory mechanisms. Genetic correlations between IQ and cognitive style indicate that they are influenced in part by shared and nonshared genetic factors. It is proposed that qualitative changes in psychological features associated with the dynamic features of cognitive activity occur at the age of 7 years.