Lecture 8

Biological factors

Genes, brain, environment, evolution.

Evolution by natural selection

Process by which certain adaptive characteristics emerge over generations.

Sir Francis Galton

Misunderstood survival of the fittest, believed rich white men in England were superior. Started the "eugenics" movement and advocated for sterilization of the poor.

Social Darwinism

Applying evolutionary theory to society, where societies and cultures compete in survival of the fittest.

Sociobiology/Evolutionary psychology

Scientific study of the influence of evolutionary biology on individual responses regarding social matters, analyzing human aggression, courtship, and child-rearing.

Evolutionary personality theory

Application of Darwin's theory of evolution, where the function of a survival characteristic evolves over time. Belief that many individual characteristics are influenced by genes.

Biological determination

Personality is determined by genes, brains, and hormones. Behavior is influenced by biological tendencies.

Examples of genetic personality types

Angelman syndrome (deletion or inactivation of genes on the maternally inherited chromosome 15),

Down's syndrome (third chromosome of 21).

Tourette Syndrome

Inherited neuropsychiatric disorder characterized by multiple physical tics and at least one vocal tic. Often associated with coprolalia, the exclamation of obscene words or socially inappropriate remarks.

Somatotypology

Three body types that influence personality.

Hans Eysenck

Proposed three basic dimensions of personality related to specific brain functions.

Eysenck's types

Extroversion-introversion, neuroticism-stability, psychoticism-superego functioning.

Introversion vs extroversion (Hans Eysenck)

Tied to central nervous system, extroverts have low brain arousal, while introverts have high brain arousal.

Temperament based on work of Pavlov

Stable individual differences in emotional reactivity that remain stable as children mature. Different nervous system responses to unpleasant stimuli.

4 basic aspects of temperament

Social, emotionality, activity, impulsive-aggressive.

Brain hemispheric hypothesis

Left hemisphere associated with positive emotions and analytic thinking, while right hemisphere associated with negative emotions and intuitive thinking.

Neuroimaging

EEG, PET scans, fMRI.

EEG

Reveals neuronal activity in different brain regions.

PET scans

Functional neuroimaging technique that demonstrates glucose metabolism in the brain under arousal.

fMRI scans

Functional neuroimaging technique that measures brain activity by detecting changes in blood flow.

Types of neurotransmitters

Dopamine, norepinephrine, serotonin.