2.1: Interaction of Heredity and Environment Flashcards
Nature vs. Nurture (Are we more influenced by our genes and heredity or by our experiences?)
Biological psychologists in particular are interested in studying the links between our biological (genes, neurons, etc.) processes and psychological processes.
Ways that Psychologists Can Study the Influence of Nature vs. Nurture
Mutations, chromosome pairs, DNA, genes, or even the entire human genome to see where minute differences can come into play.
Twin and Adoption Studies.
Behavior Geneticists
Interested in studying the power and limits of genetic and environmental influences on behavior.
Twin and Adoption Studies
If we are able to study identical twins that were separated at birth, we can compare and contrast them. We would look for similarities and differences in their abilities, personalities, and traits to get an idea of what was more influential - nature or nurture. We can further make comparisons between fraternal twins and siblings raised in the same family to gain additional insights.
Identical (Monozygotic) Twins
Develop from the same fertilized egg that eventually splits into two.
Each twin has the same genes, but not the same number of copies of those genes.
This may explain some small differences between the two twins or why one is more at risk for illnesses.
Identical twins also share the same prenatal environment (placenta) but one may receive slightly better nourishment and care.
Thomas Bouchard’s Study
A famous study conducted by Thomas Bouchard found that the IQ of twins living separately after birth had a correlation of 0.69 while the IQ of twins living together had a correlation of 0.88.
The scores found that environment had some effect on IQ scores, but it is still heavily influenced by genetics.
Effective Psychological Environment
Physical similarities causing others to treat the twins in similar ways.
Heritability
To understand the variations that exist between individuals being studied.
Tells us how much of the variation that exists between a group of individuals is due to genetics.
NOT the amount or percent of a given trait that is inherited. It is instead an explanation of the differences that exist between us related to genetic factors.
Molecular Geneticists
Study the molecular structure and function of genes and how they play a role on our behavior.
They find genes that allow us to have traits such as body weight, sexual orientation, and extraversion and attempt to find out which specific genes influence each of these behaviors.
Epigenetics
When discussing the nature vs. nurture debate it is important to note that often both play an important role in our development and behavior.
Epigeneticists look at how the environment influences how our genes are expressed without an actual change in DNA.
What Can Impact the Study of Epigenetics?
There are environmental changes that can explain why each child in a family is different, despite their same genetic background.
Mutations
Random errors that occur during gene replication that lead to a change.
Evolutionary Psychologists
Focus on the principles of natural selection to explain our behavior and the mind.
This principle states that we are more likely to inherit and pass along traits that have been vital to our survival as a species.
Charles Darwin has an large influence in this field of psychology.
The Biopsychosocial Approach
It is important to note that biological (genes), psychological (gene expression + beliefs), and social-cultural (peer influence) influences all play a part in our individual development.
Contrary to other approaches, psychologists who have a biopsychosocial approach do not focus on specific influences of thinking and behavior. Instead, they believe that rules we use to view the world affect our way of thinking and behaving.
Moreover, biological and social influences are equally responsible for our decision.
Extroversion
- Genetic tendency.
- How the person was conditioned to be extroverted.
- Social pressures (conformity).
