Chapter 4: Biological Theories -- Genetics, Physiology and Evolution

Question 1

Behavioural Genetics

Answer 1

This refers to the use of genetic methods to determine the origins of individual differences in behaviour. Essentially, it is attributing personality to genetics.

Question 2

Nature vs. Nurture

Answer 2

In the politics of behavioural genetics, it had heavy focus on the nature side, discounting the role of parenting. This promoted the perception that “your genes are what you are.”

Question 3

Political Agendas

Answer 3

Biological determinism was used to minimize responsibility, and argue a lack of free will against crimes.

Question 4

Biological Determinism

Answer 4

A belief that one’s biology is what influences behaviour. For instance, “my genes made me do it!”

Question 5

Eugenics

Answer 5

To encourage or discourage certain genes from existing in the population gene pool. This eliminated diversity and was weaponized against marginalized groups.

Question 6

Francis Galton

Answer 6

Coined the term Eugenics. Conducted research to discover that not just physical traits could be passed down but also personality. Intended to use eugenics to make society better.

Question 7

World War II

Answer 7

Nazis used eugenics as a mask to reason the genocide of Jews.

Question 8

Alberta Sterilization Act

Answer 8

The government believed that the adults who had lower IQ would have offsprings of lower IQ as well. To “solve” this issue, they turned to eugenics and forced sterilization on children who were “mentally weak”. Although they did not account for differences relating to socioeconomic factors, or environment (rural areas vs. urban).

Question 9

What trait is super nature-based?

Answer 9

Aggression!

Question 10

Richard Tremblay

Answer 10

Attempted to study the age in which we can predict and intervene in aggression in adolescent boys. Started observations in high school male adolescents and eventually rolled back his hypothesis until he began to examine fetuses.

Question 11

Heritability

Answer 11

The number of individual differences that can be attributed to genetics. This does NOT mean the probability of inheriting the trait. It simply indicates the number of population differences that are a result of genetics.

Question 12

How do you refine the limitation of personality being affected by BOTH Nature AND Nurture?

Answer 12

We need to measure both factors! We need to examine the correlation between the individual’s traits and the different aspects of their environment. Example: The number of books in a child’s home vs. IQ.

Question 13

Monozygotic Twins

Answer 13

One zygote (one sperm and one egg) splits into two. They are identical in DNA and appearance and share the same genetic material and environment.

Question 14

Dizygotic Twins

Answer 14

Two zygotes formed due to two eggs being released. Genetically different just like other/regular siblings, although they share a prenatal experience/environment.

Question 15

Occupational Preferences

Answer 15

When looking at the occupational preferences between the parent’s actual job and child’s preferences, what was found was that the child’s ideal career may be different, but the attributes of the ideal career are similar in values the parents hold. Preferences of occupational attributes have high heritability.

Question 16

Drinking and Smoking

Answer 16

Both are highly heritable and are related to high extraversion, sensation seekings and neuroticism.

Monozygotic twins are likely to have a twin that also smokes, and alcoholism has high heritability (but not social drinking).

Question 17

Molecular Genetics

Answer 17

Specific genes are associated with specific traits.

Question 18

Dopamine Alleles

Answer 18

Long repeated allele versions cause individuals to have a higher threshold for dopamine response, meaning they need more stimulus and novel experiences to be satisfied.

Short repeated allele versions cause individuals to have lower dopamine thresholds for dopamine response, meaning they are easily satisfied and too much stimulus may be overwhelming.

Question 19

Cultural Differences in Dopamine

Answer 19

Longer alleles are more prevalent in Americans as opposed to Asians, accounting for cultural differences.

Question 20

Galen Medicine

Answer 20

In Medival Europe, they contributed personality to 4 humours/bodily fluids:

1) Phlegm (Water) – Passive, calm, thoughtful
2) Blood (Air) – Happy, outgoing, lively
3) Yellow Bile (Fire) – Unstable, Aggressive
4) Black Bile (Earth) – Unhappy, Pessimistic

Question 21

Ayurveda Medicine

Answer 21

In India, they tied personality to body types.

1) Vata: Thin, light and airy, dry skin = Anxious, active and creative mind.
2) Pitta: Medium build, prone to inflammation, hot = Intelligent, focused, energetic and intense.
3) Kapha: Stocky build = Nurturing, compassionate, more grounded.

Question 22

Phrenology

Answer 22

In North America, it was believed that the measurements of your heads tied to personality. The bumps around your head would indicate what parts of the brain were under-developed or over-developed.

Question 23

Hebb’s Theory of Arousal

Answer 23

There is an optimal level of arousal and alertness.
Too low/under aroused: Sleepy, tired, bored.
Too high/over aroused: Anxious, agitated, overworked.

Question 24

Cortisol Levels and Personality

Answer 24

Introversion and Extraversion are biologically based as the blood-brain barrier allows for more cortisol for introverts and less for extraverts.

Question 25

What part of the brain is in charge of personality?

Answer 25

The prefrontal cortex. It also is in charge of self-control, planning, judgement, rationalizing, and time and task management.

Question 26

Left Hemisphere in Prefrontal Cortex

Answer 26

Calm and emotionally stable. This hemisphere deals with pleasant emotions! The calmer your brain, the greater your left-side asymmetry.

Question 27

Right Hemisphere in Prefrontal Cortex

Answer 27

Neurotic. This hemisphere deals with unpleasant emotions. The more asymmetric your right hemisphere, the more preoccupied your brain tends to be.

Question 28

Gray’s Theory of Behavioural Activation System (BAS)

Answer 28

Motivation through reward/gain! Sensation-seeking and impulsive, as well as more positive outlook and likeliness to see the possibilities of wins. Maps highly with Eysenck’s definition of Extraversion.

Question 29

Gray’s Theory of Behavioural Inhibition System (BIS)

Answer 29

Motivated by punishment avoidance. Preoccupied with negative outcomes, and tends to be anxious, as well as possess a negative outlook and focus on the possibilities to lose. Maps highly with Eysenck’s definition of Neuroticism.

Question 30

Neurotransmitters and Personality

Answer 30

Dopamine: People with low dopamine thresholds need less stimulus to be satisfied. Those with high dopamine thresholds thend to be thrill-seekers.
Serotonin: In charge of mood regulation. Too low may lead to depression, while too high may lead to hypomania.
Norepinephrine: Linked to our levels of adrenaline, and is reward-dependent.

Question 31

Cooperation vs. Competition

Answer 31

Must be balanced because too much of one causes the other to become the more beneficial option.