Discuss+how+and+why+particular+methods+are+used+at+the+biological+level+of+analysis.+(Elizabeth)

Much of the genetic research in humans is based on correlational studies. Researchers look at how different variables may co-vary. There are also TWIN, FAMILY, and ADOPTION studies. These are used to study possible correlations of genetic inheritance and behavior. Researchers prefer to study with twins because they share common genetic material. FAMILY STUDIES are a more representative sample of the general population. ADOPTION STUDIES allow the most direct comparison of genetic and environmental influences of behavior Adoption studies are criticized because the children are not representative of the general population. Also, adoption agencies tend to use selective placement when finding homes for children. They try place children with families who are similar in as many ways as possible to the natural parents. Therefore, the effects of genetic inheritance may be difficult to separate from the influences of the environment.
 * Correlational studies establish that there is a relationship between variables, but the researcher doesn't manipulate an independent variable as in an experiment, so no cause and effect can be determined
 * Monozygotic twins (MZ) are genetically identical because they are formed from one fertilized egg that splits into two;
 * of the same sex
 * look much alike
 * Dizygotic twins (DZ) are from two eggs and will not be closer genetically than brothers and sisters;
 * 50% of genes will be in common
 * not necessarily of the same sex **(important, because psychologists use these different degrees of genetic relationship as a basis for their hypotheses.)
 * The correlation found in twin research is called the CONCORDANCE RATE.
 * A child inherits half its genes from the mother and the other half from the father;
 * ordinary brothers and sisters will share 50% of their genes with each other
 * grandparents will share 25% of their genes with their grandchildren
 * 1st cousins will have 12.5% of their genes in common with each other.
 * These different degrees of genetic relatedness are compared with behavior
 * The notion is that concordance rates will increase if heritability is high and vice versa
 * Adopted or foster children generally share none of their genes with their adoptive parents, but they share 50% of the genes with their natural mother
 * It would be reasonable to suppose that if the heritability of a behavior is high and environment has little part to play, that the behavior of the adopted children should correlate more strongly with the behavior of their natural mother than their adoptive mother

Experiment: Lashely, Freider - Caffeine slows pup learning LoBue - snake in grass

Correlational Studies: [] : Alcohol and prefrontal cortex study (De Bellis)

Case Studies: [] : Phineas Gage [] : Broca's Area