PSYCH 150 Lecture Notes - Lecture 5: Phenylketonuria, Intellectual Disability, Phenylalanine
Document Summary
Genetic influences on behavior, cognition, and emotion. Fraternal/dizygotic twins (dz): share 50% of their genes. Identical twins reared together vs fraternal twins reared together. Identical twins reared together vs identical twins reared apart. If correlations are higher for identical twins reared together environment. Higher correlations between identical twins than fraternal twins. Percentage of variability in individual differences in a characteristic accounted by genetics. H = 2x [r (monozygotic reared together) - r (dizygotic reared together)] Estimate is much lower for social attitudes (conservatism, religiosity, racial integration, tv viewing, love styles) than for personality or physical traits. Shared environment (se) versus nonshared environment (nse) Se: environments shared by siblings reared together. Nse: environments not shared by siblings reared together. Environment exerts its greatest influence through nonshared experiences; those that are unique to each individual. If correlations are higher for identical twins genes. Estimates depend on the environment and the sample. Biological processes can be altered to change expression of genes.
