Topic 2 Medical Model

Question 1

Background?

Answer 1

3 ‘biological’ explanations of mental illness:

• The biochemical explanation
• The genetic explanation
• Brain abnormality as an explanation

Question 2

Bio chemical explanation?

Answer 2

• Nerve cells send messages as electrical impulses
• The impulse travels to the end of the nerve cell
• To reach the next cell, it must cross a gap called a synapse
• Neurotransmitters are released into the synapse in response to the impulse
• They diffuse across the synapse and can:

-Bind to receptors on the next cell (post-synaptic cell)

• Be broken down by enzymes

-Be reabsorbed by the original cell (pre-synaptic cell)

• If enough neurotransmitters bind, a new impulse is triggered in the next cell

Question 3

Biochemical explanation of depression?

Answer 3

Brain chemicals (neurotransmitters) may become unbalanced in mental health issues

It’s unclear if the imbalance causes the disorder or vice versa

One theory of depression links it to low serotonin
Low serotonin is linked to:
- Low mood
- Poor sleep
- Lack of motivation (apathy)
Fear

Question 4

How are messages passed between nerve cells?

Answer 4

-Messages are passed across a gap called a synapse

• Neurotransmitters like serotonin carry the message across
• Released from the pre-synaptic cell and bind to receptors on the post-synaptic cell

-This causes a new electrical signal to be passed along

Question 5

What happens to serotonin after it stimulates the next cell?

Answer 5

After stimulation, serotonin is reabsorbed by the pre-synaptic cell
This process is called reuptake

Question 6

What happens if serotonin levels are too low?

Answer 6

• Serotonin may be reabsorbed too quickly
• The message may not be passed effectively
• Can result in signals not reaching the brain areas that control mood
• May cause the person to not feel happy even when they should

Question 7

How does this relate to depression and treatment?

Answer 7

• Low serotonin levels may lead to depression
• SSRIs (Selective Serotonin Reuptake Inhibitors) help by blocking reuptake
• This allows more serotonin to stay in the synapse and improve mood

Question 8

Biochemical explanation - schizophrenia

Answer 8

Dopamine may play a role in schizophrenia

Too much dopamine or too many dopamine receptors could be a cause

Drugs like amphetamines or LSD (which increase dopamine) can cause similar symptoms (e.g. hallucinations, delusions)

Antipsychotic drugs help by blocking dopamine receptors, reducing dopamine overload

Question 9

Genetic explanation of mental illness

Answer 9

Mental illness may be inherited through genes

This creates a predisposition (increased risk), but an environmental trigger is often needed

Siblings may differ—one may develop the disorder while another doesn’t, due to differences in genes and environment

Question 10

Genetic explanation of mental illness

Answer 10

Gottesman’s research shows children with two parents who have schizophrenia or bipolar disorder have a higher risk of developing it
But the risk is not 100%, so other factors (like environment or individual differences) must also play a role