Psychology: the scientific study of mind and brain to explain behavior
- Goal: Why do people do what they do? Ultimately predict what people will do
- Why do we need science for that? → because common sense fails
- How do the mind and the brain relate? → the mind (mental activity) is
produced by biochemical processes in the brain
Topic 1: Genes and Evolution (p. 3-4; 67; 101-112)
1. What are chromosomes, DNA, and genes, and what is the relationship between the three?
2. What is meant by genetic expression, genotype, and phenotype?
3. Can you explain how genes are passed from parents to children?
4. What is meant exactly by evolution through natural selection?
5. Which role do evolution, genes and environment play in behavior?
6. What is behavioral genetics and which methods are used here?
7. What is meant by heritability?
The Genetic basis
Does “a violent person have violent genes”? → Answer changed throughout history:
→ 70s: No, it is just bad behavior
→ 90s: yes, it is due to their genes
→ Today: behavior is the result of the interaction between genes x
environment
- Limit set by genes, but under diff environments a lot of
variety is possible
Genes, chromosomes and DNA
1. DNA: contains the chemical code in cells for building/operating living organisms.
2. Genes: the meaningful sections of the DNA molecule that provides
instructions for making protein (amino acids) (>30,000 genes → only 2x
amount of a fruitfly)
3. Chromosomes: long coiled structures made of DNA and proteins
a. 23 pairs. 23th determines sex: XX or XY
b. Human Chromosome 2 = combination of two ape chromosomes
- Gene expression: whether a gene is turned “on” or “off”; extent
to which a gene is transcribed into amino acids (protein) (butterfly
wing color depends on season it is born in) → In each cell, some
genes are expressed at any point in time and others are not (the result of
Methylation)
- Controlled by the biochemical environment inside the cell (timing,
behavior (whether you exercise or not) etc)→ environment plays crucial
role in shaping us by affecting gene expression
- Genes determine the proteins that CAN be produced and the environment
determine the proteins that WILL be produced
,Genome, genotype and phenotype
1. Genome: complete set of DNA of an organism/species, all possible physical options
2. Genotype: organism’s specific set of genes, determined at conception (Individuals vary)
a. shaped by evolution over the years → Darwin’s evolution theory
3. Phenotype: characteristics expressed: genotype x environment (past and present) and
a. one gene pair.
b. Interaction tween multiple gene pairs → polygenetic inheritance (skin
color, traits)
- Twins have the same genotype (share 100% genes), but different
environment, resulting in different ways in which their genes are expressed →
look different + diff phenotype
Each gene is paired with another gene
- The pairs are located at corresponding positions on pairs of
chromosomes.
- Allele is one specific variant of a gene
- Dominant: expressed when you have one copy of the allele
- recessive: only expressed when paired with another
recessive gene from the other parent
- mother and father both carry a dominant gene for brown eyes and a
recessive gene for blue eyes. probability of brown eyes = 0,75
Evolution by natural selection
- Genome is shaped by the key mechanism of evolution: natural selection
(Darwin’s evolution theory);. 3 conditions for NS:
1. There is variation in genotype among individuals of a populations
2. Individuals with a certain trait survive and reproduce at higher rates than others
3. The trait associated with this advantage is passed from parents to offspring
a. Variations in genotype are passed from generation to generation
b. Specific traits will be better represented in the next generation: What
matters is the survival of genes, not the survival of individuals
- Evolution does not somehow improve organisms and only leads to rigid
behavioral patterns → Just adapt better to environment (evidence: fossil
records + pseudogenes)
Nature (genes) versus Nurture (environment)
- nature nurture debate = irrelevant → interaction between genes and
environment!
- Our biological systems constantly interacts with and adapt to our environmental and
cultural contexts, different genes are expressed in different environments!
Behavioral Genetics and Its Methods
= the study of the interaction between genes and environment, different methods used:
, - Twin studies: Compare behavioral similarities between:
1. Monozygotic Twins: Identical twins,share 100% of their genes
2. Dizygotic (DZ) Twins: Fraternal twins, share 50% of their genes
- Twins reared apart
- Adoption studies
Heritability vs hereditary
1. Heredity: the biological transmission of traits from parents to offspring via genes
2. Heritability: population-level measure of differences (never applies to the individual)
Topic 2: The brain and the nervous system (P.67- 99)
‘’We've got the same nervous system basically that chimps do. There is only one difference
which is, we’ve got like three times as many neurons’’
1. What are the structure and function of the neuron?
2. How do neurons communicate with each other?
3. How does the brain communicate with the body?
4. Which different methods are used to study the nervous system, and what exactly does
each of these methods measure?
5. What are the main components of the nervous system and the brain?
6. What is meant by the term lateralization?
7. What are the main projection areas in the cortex
The nervous system is made up of two basic kinds of cells
1. Glia: Cells that support neurons
2. Neurons: signal to receive, process, and transmit information through the brain and
body, different types of neurons
a. sensory (afferent) neurons: Carries these signals inward from the sensory
receptors and body to the central nervous system (brain and spinal cord =
nervous system)
i. detect environmental stimuli (like warmth, pressure, or light) and turn
them into electrical signals.
b. Motor (efferent) neurons: Carry these signals outward from the central nervous
system to muscles or glands to trigger an action (lifting your arm)
i. Direct muscles to contract or relax to produce movement
c. Interneurons: in between the other categories
- parts:
d. Dendrites: Branch-like structures that receive chemical signals from other cells
e. Axon: outgrowth that transmits electrical impulses away from the
cell body (soma) to the terminal buttons. nerves = bundles of
axons
f. Membrane: outer cover of the cell
i. presynaptic neuron: end of neuron that sends information
to..
, ii. postsynaptic neuron: receiving cell (dendrite).
g. Synaps: the end of neurons that bind them to each other = how neurons interact
= Gap where messages/signals pass from one neuron to neuron using
neurotransmitters (chemicals) → so they get stimulated
- lock and key model: keeping different flows of information apart: a neurotransmitter will
only affect a postsynaptic membrane if its shape fits precisely into the receptor.
- effect is terminated by
a. Autoreceptors: detect when enough neurotransmitter is in the gap, signaling the
cell to stop releasing more
b. synaptic reuptake: sending neuron vacuums the excess neurotransmitters back
up into itself to be recycled and reused.
c. enzymes: proteins break down and destroy the remaining neurotransmitters so
they can no longer bind to the receiving neuron
i. binding of a neurotransmitter with receptor procedures an excitatory
(depolarizes: neuron more likely to fire) or inhibitory signal
(hyperpolarizes: less likely to fire)
- different neurotransmitters are associated with different functions
1. GABA: primary inhibitory neurotransmitter, meaning it calms neural activity to
reduce anxiety, stress, and over-excitation
2. Glutamate: excitatory transmitter (learning and memory)
3. Serotonin: Emotional states, impulse control, and dreaming.
4. Dopamine: Reward, motivation, and motor control for voluntary movement
5. Endorphins: Pain reduction and natural reward/pleasure
6. Norepinephrine: attention, arousal
- Goal: Why do people do what they do? Ultimately predict what people will do
- Why do we need science for that? → because common sense fails
- How do the mind and the brain relate? → the mind (mental activity) is
produced by biochemical processes in the brain
Topic 1: Genes and Evolution (p. 3-4; 67; 101-112)
1. What are chromosomes, DNA, and genes, and what is the relationship between the three?
2. What is meant by genetic expression, genotype, and phenotype?
3. Can you explain how genes are passed from parents to children?
4. What is meant exactly by evolution through natural selection?
5. Which role do evolution, genes and environment play in behavior?
6. What is behavioral genetics and which methods are used here?
7. What is meant by heritability?
The Genetic basis
Does “a violent person have violent genes”? → Answer changed throughout history:
→ 70s: No, it is just bad behavior
→ 90s: yes, it is due to their genes
→ Today: behavior is the result of the interaction between genes x
environment
- Limit set by genes, but under diff environments a lot of
variety is possible
Genes, chromosomes and DNA
1. DNA: contains the chemical code in cells for building/operating living organisms.
2. Genes: the meaningful sections of the DNA molecule that provides
instructions for making protein (amino acids) (>30,000 genes → only 2x
amount of a fruitfly)
3. Chromosomes: long coiled structures made of DNA and proteins
a. 23 pairs. 23th determines sex: XX or XY
b. Human Chromosome 2 = combination of two ape chromosomes
- Gene expression: whether a gene is turned “on” or “off”; extent
to which a gene is transcribed into amino acids (protein) (butterfly
wing color depends on season it is born in) → In each cell, some
genes are expressed at any point in time and others are not (the result of
Methylation)
- Controlled by the biochemical environment inside the cell (timing,
behavior (whether you exercise or not) etc)→ environment plays crucial
role in shaping us by affecting gene expression
- Genes determine the proteins that CAN be produced and the environment
determine the proteins that WILL be produced
,Genome, genotype and phenotype
1. Genome: complete set of DNA of an organism/species, all possible physical options
2. Genotype: organism’s specific set of genes, determined at conception (Individuals vary)
a. shaped by evolution over the years → Darwin’s evolution theory
3. Phenotype: characteristics expressed: genotype x environment (past and present) and
a. one gene pair.
b. Interaction tween multiple gene pairs → polygenetic inheritance (skin
color, traits)
- Twins have the same genotype (share 100% genes), but different
environment, resulting in different ways in which their genes are expressed →
look different + diff phenotype
Each gene is paired with another gene
- The pairs are located at corresponding positions on pairs of
chromosomes.
- Allele is one specific variant of a gene
- Dominant: expressed when you have one copy of the allele
- recessive: only expressed when paired with another
recessive gene from the other parent
- mother and father both carry a dominant gene for brown eyes and a
recessive gene for blue eyes. probability of brown eyes = 0,75
Evolution by natural selection
- Genome is shaped by the key mechanism of evolution: natural selection
(Darwin’s evolution theory);. 3 conditions for NS:
1. There is variation in genotype among individuals of a populations
2. Individuals with a certain trait survive and reproduce at higher rates than others
3. The trait associated with this advantage is passed from parents to offspring
a. Variations in genotype are passed from generation to generation
b. Specific traits will be better represented in the next generation: What
matters is the survival of genes, not the survival of individuals
- Evolution does not somehow improve organisms and only leads to rigid
behavioral patterns → Just adapt better to environment (evidence: fossil
records + pseudogenes)
Nature (genes) versus Nurture (environment)
- nature nurture debate = irrelevant → interaction between genes and
environment!
- Our biological systems constantly interacts with and adapt to our environmental and
cultural contexts, different genes are expressed in different environments!
Behavioral Genetics and Its Methods
= the study of the interaction between genes and environment, different methods used:
, - Twin studies: Compare behavioral similarities between:
1. Monozygotic Twins: Identical twins,share 100% of their genes
2. Dizygotic (DZ) Twins: Fraternal twins, share 50% of their genes
- Twins reared apart
- Adoption studies
Heritability vs hereditary
1. Heredity: the biological transmission of traits from parents to offspring via genes
2. Heritability: population-level measure of differences (never applies to the individual)
Topic 2: The brain and the nervous system (P.67- 99)
‘’We've got the same nervous system basically that chimps do. There is only one difference
which is, we’ve got like three times as many neurons’’
1. What are the structure and function of the neuron?
2. How do neurons communicate with each other?
3. How does the brain communicate with the body?
4. Which different methods are used to study the nervous system, and what exactly does
each of these methods measure?
5. What are the main components of the nervous system and the brain?
6. What is meant by the term lateralization?
7. What are the main projection areas in the cortex
The nervous system is made up of two basic kinds of cells
1. Glia: Cells that support neurons
2. Neurons: signal to receive, process, and transmit information through the brain and
body, different types of neurons
a. sensory (afferent) neurons: Carries these signals inward from the sensory
receptors and body to the central nervous system (brain and spinal cord =
nervous system)
i. detect environmental stimuli (like warmth, pressure, or light) and turn
them into electrical signals.
b. Motor (efferent) neurons: Carry these signals outward from the central nervous
system to muscles or glands to trigger an action (lifting your arm)
i. Direct muscles to contract or relax to produce movement
c. Interneurons: in between the other categories
- parts:
d. Dendrites: Branch-like structures that receive chemical signals from other cells
e. Axon: outgrowth that transmits electrical impulses away from the
cell body (soma) to the terminal buttons. nerves = bundles of
axons
f. Membrane: outer cover of the cell
i. presynaptic neuron: end of neuron that sends information
to..
, ii. postsynaptic neuron: receiving cell (dendrite).
g. Synaps: the end of neurons that bind them to each other = how neurons interact
= Gap where messages/signals pass from one neuron to neuron using
neurotransmitters (chemicals) → so they get stimulated
- lock and key model: keeping different flows of information apart: a neurotransmitter will
only affect a postsynaptic membrane if its shape fits precisely into the receptor.
- effect is terminated by
a. Autoreceptors: detect when enough neurotransmitter is in the gap, signaling the
cell to stop releasing more
b. synaptic reuptake: sending neuron vacuums the excess neurotransmitters back
up into itself to be recycled and reused.
c. enzymes: proteins break down and destroy the remaining neurotransmitters so
they can no longer bind to the receiving neuron
i. binding of a neurotransmitter with receptor procedures an excitatory
(depolarizes: neuron more likely to fire) or inhibitory signal
(hyperpolarizes: less likely to fire)
- different neurotransmitters are associated with different functions
1. GABA: primary inhibitory neurotransmitter, meaning it calms neural activity to
reduce anxiety, stress, and over-excitation
2. Glutamate: excitatory transmitter (learning and memory)
3. Serotonin: Emotional states, impulse control, and dreaming.
4. Dopamine: Reward, motivation, and motor control for voluntary movement
5. Endorphins: Pain reduction and natural reward/pleasure
6. Norepinephrine: attention, arousal
