Child psychology is very complicated because the environment always has a role. In thequestion of “nature vs nurture,” it’s pretty much always both. The focus of this course is on howgenes and environment interact with each otherJohn B Watson declared that, with the right environment, a child could be turned into prettymuch anything. John Locke called this tabula rasa meaning “blank slate.” And as Watsondemonstrated with his “Little Albert” experiment, you can condition the baby to feel lots ofemotions.This idea (tabula rasa) that behavior is rooted entirely in the environment is the main thesis ofthe learning perspective, whereas the biological perspective states that some behavior isrooted in the genetics of a person. For a counterexample to the learning perspective, LittleAlbert could be conditioned to fear white rats but not white rabbits. (This means that badbehavior could be blamed on bad genes in the parents.)Gesell’s Maturational Theory says that behavior is more predetermined. Basically, kids aredifferent from the start.The biological perspective is flawed because it leads to elitist, eugenics or outright racist lines ofthought. The learning perspective is flawed because some of us have certain inborn, instinctualbehaviors.Basically, there is no nurture vs nature debate. It is a false dichotomy. Both exist together, andboth influence each other._____At a microscopic level, inside the nucleus of each human cell there are 23 pairs ofchromosomes. These chromosomes consist of DNA, and sections of DNA contain genes,which are the codes that determine things like hair color, eye color, etc.Not everything that is coded happens.Genotype = what the DNA codesPhenotype = what actually happens (both physically and psychologically)Dominant genes are stronger than recessive genes, meaning that if both are in DNA, thedominant genes emerge. This often explains the disconnect between genotype and phenotypeMost diseases are recessive (except for Huntington’s)Interestingly, sometimes a resistance to a disease is also recessive (Sickle Cell Trait is therecessive sickle cell that provides resistance to Malaria)Heterozygous = if you have one dominant, one recessiveHomozygous recessive = if you have two recessiveHomozygous dominant = if you have two dominantBehavioral Genetics is the branch of genetics that deals with the inheritance of behavioral andpsychological traits. It is all incredibly complicated____Most traits are polygenic (meaning they are the result of many genes) + have environmentalinteractionReaction range refers to the range of possible outcomes in a population due to a subtle geneticshiftIndividual traits usually occur in a normal/bell-shaped curveWe’ve been messing with genes via selective breeding (picking who mates with who). Geneticdiversity is important so we don’t overemphasize certain traits over others, and we keep traits inthat bell curveCharacteristics most affected by heredity:● Intelligence● Psychological Disorders● Personality TraitsThere are two main kinds of genetic disorders:● Inherited Disorders: sickle-cell disease, Cystic fibrosis, Tay-Sachs, Huntington’s● Abnormal Chromosomes: when meiosis goes wrong and it leads to wrongchromosomes, like Down Syndrome____The first way genes affect behavior is via passive gene-environment interaction. Parentsprovide gene and environmentThe second way is via evocative gene-environment interaction, where genes influencebehavior, which evokes an environmental reactionThe third way is via active gene-environment interaction, where genes drive the individual tonew and exciting environments. This is called niche-picking_____We use twin and adoption studies to tackle the nature vs nurture argument because(identical) twins have 100% of the same genes, but they might be given up for adoption andraised in different environments.There are two kinds of twins: monozygotic (identical, one egg) and dizygotic (fraternal, twoeggs). We are generally referring to monozygoticThe problem with these studies is that we never know whether someone behaved because oftheir genes or in spite of their genes.Besides twin/adoption studies, we can use DNA markers to examine specific alleles and dogenetic testing.____We can look at what genes correspond with what diseases. Williams syndrome seems tocorrelate with chromosome 7, for example. During meiosis, the process that creates spermsand eggs, these genetic diseases arise from spontaneous mutations.Unfortunately, behavioral traits cannot be so easily linked to personality, often because of thegene-environment interactions above. Genes might just create something else that leads tothose things; for example, people with symmetrical faces tend to be more popular____There are a few ethics to follow:● We want the assent of the child. While children cannot get the exact comprehension ofthe experiment, we want their agreement nonetheless.a. For children that are too young, we often need their parents around to calm themdown and get the kids to have fun and enjoy themselves. This can curvegeneralizability, unfortunately● As a result, we also get the informed consent of the parents: we need to tell themexactly what is going on and we need them to agree● We have to make sure what we are doing does more good than harm (the hippocraticoath)● Finally, we need explicit permission from the parents and children to show their dataFor all of these reasons and more, there are some studies we simply cannot do because of theethics they would violate.____All good studies start with correlations. We often develop a hypothesis for the purpose ofexperiments by first observing and make