User:Trippingrabbit/sandbox

Nature vs. Nurture is a long debated issue in psychology dividing those who view behavior as being primaraly inherited via genetics or learned from ones enviroment. Many psychological theories throughout history have favored one of these two views in attempting to explain human behaviors such as personality, temperment, intelligence and sexuallity. Although thoday it is generally accepted that both enviroment as well as genetic factors play a part in human behavior the exact degree of influence is still debated.

Origins
Although the Nature vs. Nurture debate is primaraly associated with psychological theories its roots can be traced back to early philisophical movements. Early theories of human knowledge were proposed by anciant Greek philosophers such as Plato who held the belief that humans were born with prexisting knowledge, a notion that would become the basis for such movements as Nativism and Innatism. Others including Platos own student Aristotle would counter this claim by maintaining that human knowledge is not innate but aquired through a persons observations and interaction with the world, a concept that would form the basis for the philosophy of Empiricism. Many philisophic theories which followed could be associated with one of these two traditions.

In the Late seventeenth century English philosopher and physician John Locke would elaborate on the empiricist view of knowledge with his Tabula rasa (Blank slate) theory. Locke saw the influence of the enviroment as being the main contributer to knowledge and experience. Locke saw humans as being born a blnk slate with very limited innate knowledge and it was upon this black slate in which knowledge and experience would be imprited on. The idea of humans lacking innate knowledge at birth would eventually be adopted by psychologists involved in the feild of behaviorism who saw human behavior as being learned through conditioning.

Advancements in Science
Throughout the ninteenth century a number of advancement in science and the understanding of genes and heredity would offer, for some, evidence for the influence of natural factors in human behavior. Charles Darwin became one of the most well know figures from this period, due in part to his research on evolution and natural selection. Darwin was able to show that changes in generations of organisms, over time, lead to a variety of traits, which may or may not be benifitial for survival. The traits that are benificial result in higher rates of survival and are passed on to later generations. During the same period Gregor Mendel, an Augustinian monk would conduct experiments on pea plants studying how traits were inherited throughout generations. Although not recognized during his lifetime his work would become the basis for the field of Genetics. These as well as other discoveries made during this time would be applied by future scientists and psychologist and form the basis for numerous theories of behavior.

Important Figures
Throughout the ninetenth and twentith centuries many notable and influential figures would apply the concepts originated by early Nativists and Empiricists to the field of psychology. Many psychologists and scientists of this era sought to understand human behavior rather than the acquisition of knowledge as the early philosophers did. Prominant psychologists during this time developed theories to explain the differences in human behavior leading to the establishment of different psychological fields such as behaviorism and cognitive psychology.

Francis Galton: (1822-1911) The cousin of Charles Darwin, Galton was heavily influenced by Darwin’s work. It was Galton who first coined the phrase Nature vs. Nurture in his 1874 work, English man of science: Their Nature and Nurture. Galton’s work favored the Nature perspective of the Nature vs. Nurture debate. Galton saw the influence hereditary traits in humans as the most important factor in human behavior. Gallons work within the early field of genetics would eventually lead to his development of the controversial Eugenics Movement, which sought to limit the reproduction of people with genetic defects and promote reproduction among those who were seen as having desirable genetic traits.

Sigmund Freud: (1856-1939) Regarded as the father of Psychoanalysis Freud’s work focused on the influence of unconscious forces stemming mostly from ones early childhood. He theorized the existence of unconscious drives known as the ID, Ego and Super Ego are in constant conflict with one another resulting in different behaviors. Although Freud acknowledged the presence of innate unconscious forces that were shared by all humans, such as the Oedipus complex for males and the Electra complex for females, his theories favored the nurture perspective stressing the importance of health childhood experiences to prevent abnormal behavior later in life.

John B. Watson: (1878-1958) Often regarded as the founder of the field of behaviorism Watson saw human behavior as shaped by ones environment and the consequences of previous actions. Watson expanded on previous research by Ivan Pavlov by showing that classical conditioning could be used to shape behavior. In the Little Albert experiment Watson presented a rat to infant child followed by a loud noise that scared the child. By pairing the loud noise with the rat Watson was able to condition a fear response in Albert of not only rats but all furry objects. Watsons research would be replicated by future behaviorists and provide evidence for the environments influence on behavior.

Hans Eyseneck: (1916-1997) A German psychologist who focused on human personality, Eyseneck saw an individual’s genes as being more influential in determining a person’s behavior than many other psychologists. Bases on his research of intelligence, Eyseneck concluded that intelligence in humans was 80% inherited with only 20% being attributed to ones environment. Although Eyseneck himself was not a supporter of Eugenics, he did cause controversy by suggesting that humans were not equal and that career opportunities should go to those with higher ability’s first.

Twin Studies
Twin studies have been to date one of the most valuable insights to the effects that genetics and environment might have on an individual’s personality and behavior. Twins both identical and fraternal share more genetic similarities to each other than to non-related individuals. Studies done with twins raised in separate households offer a better understanding of the role environmental factors have in creating any differences.

The Minnesota Study of twins raised apart has been the most comprehensive of its kind studying the lives of one hundred monozygotic (identical) and dizygotic (fraternal) twins that have been raised apart from one another. Starting in 1979 research conducted by Thomas Bouchard found there to be a strong genetic influence on several characteristics of the twins. IQ test administered to each set of twins showed intelligence to be roughly 70% genetic in origin. In addition personality traits such as temperament, personal interests and social attitudes were show to be about as similar in twins raised apart as in those raise together.

The results of this study suggest genetics play a large role in determining human behavior, however Bouchard suggests that similarities between the separately raised twins could also be due in part to similar reactions to the environment, theorizing that individuals with many of the same genetic traits will have similar reactions to the environments which they are in leading to similar personality and behavior.

Epigenetics
A newly founded field of science, epigenetics studies changed in the expression of genes that occur without changes in DNA. Changes to histones or DNA methylation as a result of numerous biological or environmental factors can lead to such epigenetic changes. Research in behavioral epigenetics suggests that environmental stressors play a part in epigenetic changes. Studies done on rats show that one’s raised in a less nurturing environment led to increased methylation of the gene for BDNF, which increased the risk for disorders like depression and anxiety. There was also evidence that such epigenetic changes could then be passed on to further generations. Though research has so far only been in rats and such results have not been shown in humans epigenetic changes may provide new evidence for the effects of both nature and nurture.