Biological Basis of Personality

Personality Dynamics

1. Biological Basis of Personality (Discuss the relationship between genetics and personality development.) Jane H. Basto

2. BIOLOGY is the study of living organisms, divided into many specialized fields that cover their morphology, physiology, anatomy, behavior, origin, and distribution. PERSONALITY is the combination of characteristics or qualities that form an individual's distinctive character.

3. The biological approach to personality has also identified areas and pathways within the brain, as well as various  hormones  and  neurotransmitters , that are associated with the development of personality . The biological perspective on  personality  focuses on why or how personality  traits   manifest  through biology and investigates the links between personality, DNA, and processes in the brain .

4. Genetics and Personality

5. Gene s a unit of heredity that is transferred from a parent to offspring and is held to determine some characteristic of the offspring . Genetics is the study of genes, genetic variation, and heredity in living organisms . A psychologist is a professional who evaluates and studies behavior and mental processes (see also psychology). Typically, psychologists must have completed a university degree in psychology, which is a master's degree in some countries and a doctorate in others.

6. Deoxyribonucleic acid (DNA) DNA interacts with the environment determines what part of the DNA code is actually activated within an individual—in other words, which genes will be expressed. These small changes in individuals' DNA help determine each person's uniqueness—their distinct looks, abilities, brain functioning, and other characteristics that all work together to form a cohesive personality.

7. The field of behavioral genetics focuses on the relationship between genes and behavior and has given psychologists a glimpse of the link between genetics and personality . A large part of the evidence collected linking genetics and the environment to personality comes from twin studies, which compare levels of similarity in personality between genetically identical twins. 

8. In studying 350 pairs of twins , researchers found that identical twins, whether raised together or apart, have very similar personalities rather than fraternal twins.

9. It's important to point out that traits are determined not by a single gene, but by a combination of many genes, and also by environmental factors that control whether certain genes are expressed.

10. The Brain and Personality

11. The biological approach to personality has also identified areas and pathways within the brain that are associated with the development of personality. A number of theorists, believe that personality traits can be traced back to brain structures and neural mechanisms, such as  dopamine  and seratonin pathways.

12. DOPamine Dopamine is a  monoamine neurotransmitter  that has been found to promote exploratory behavior.   Dopaminergic pathways have been specifically correlated with the extraversion trait of the Five Factor Model of Personality.   The   monoamine oxidase (MAO) enzyme has a preferential affinity for dopamine, and is correlated with sensation seeking .

13. Serotonin Serotonin is a  monoamine neurotransmitter , and has been found to promote avoidance behavior through inhibitory pathways.   Specifically , serotonin has been associated with Neuroticism, Agreeableness, and Conscientiousness (traits defined by the Five Factor Model of Personality ).