Psychology · Year 13 · Schizophrenia · 3.º Período

Biological Explanations and Therapies

This topic examines the genetic basis, dopamine hypothesis, and neural correlates of schizophrenia. Students will also evaluate the effectiveness and side effects of typical and atypical antipsychotic drugs.

TL;DR:Biological explanations for schizophrenia focus on genetics, the dopamine hypothesis, and neural correlates. Students evaluate evidence from twin studies and the effectiveness of antipsychotic medications. The topic covers the evolution of the dopamine hypothesis from a simple 'too much dopamine' theory to a more complex understanding of specific pathways in the brain.

• National Curriculum Attainment Targets
• AQA A-level Psychology 7182 - 4.3.3.2
• AQA A-level Psychology 7182 - 4.3.3.3

About This Topic

Biological explanations for schizophrenia focus on genetics, the dopamine hypothesis, and neural correlates. Students evaluate evidence from twin studies and the effectiveness of antipsychotic medications. The topic covers the evolution of the dopamine hypothesis from a simple 'too much dopamine' theory to a more complex understanding of specific pathways in the brain.

This topic is a key part of the Schizophrenia unit, linking biological theory directly to clinical practice. Students must be able to weigh the benefits of typical and atypical antipsychotics against their often severe side effects. This topic particularly benefits from hands-on, student-centered approaches. Students grasp the complex neurochemistry faster when they can model the action of drugs at the synapse and debate the ethics of biological 'management' of mental illness.

Key Questions

1. How does the dopamine hypothesis explain schizophrenic symptoms?
2. What empirical evidence supports a genetic vulnerability to the disorder?
3. How effective are atypical antipsychotics compared to typical ones?

Watch Out for These Misconceptions

Common Misconception

Antipsychotic drugs 'cure' schizophrenia.

What to Teach Instead

Drugs manage symptoms but do not cure the underlying cause. If a patient stops taking them, symptoms usually return. Using a 'management vs cure' discussion helps students understand the limitations of biological therapies.

Common Misconception

Schizophrenia is caused by a single 'schizogene.'

What to Teach Instead

Schizophrenia is polygenic, meaning it involves many different genes working together. Peer-led investigations into modern genome studies help students move away from simplistic genetic explanations to a more accurate, complex view.

Active Learning Ideas

Inquiry Circle

The Dopamine Storyboard

Groups create a visual storyboard showing the evolution of the dopamine hypothesis. They must illustrate the original hypothesis (excess dopamine), the revised version (specific pathways), and how antipsychotic drugs block D2 receptors.

45 min·Small Groups

Formal Debate

Typical vs Atypical Antipsychotics

Students are assigned to represent either 'Typical' (e.g., Chlorpromazine) or 'Atypical' (e.g., Clozapine) drugs. They must debate which is more effective, considering both symptom reduction and the severity of side effects like tardive dyskinesia.

40 min·Whole Class

Think-Pair-Share

The Genetic Link

Students examine Gottesman's twin study data. Individually, they calculate the risk for different family members; in pairs, they discuss why the risk is never 100% even for identical twins, and share their conclusions about environmental factors.

30 min·Pairs

Frequently Asked Questions

What is the dopamine hypothesis of schizophrenia?

The dopamine hypothesis suggests that schizophrenia is linked to abnormal levels of the neurotransmitter dopamine. The original version focused on hyperdopaminergia (high levels) in the subcortex, particularly the mesolimbic pathway, which is linked to positive symptoms. More recent versions also include hypodopaminergia (low levels) in the prefrontal cortex, linked to negative symptoms.

How do typical antipsychotics work?

Typical antipsychotics, like Chlorpromazine, work as dopamine antagonists. They bind to D2 receptors in the brain, blocking the action of dopamine. This reduces the over-activity in the mesolimbic pathway, effectively dampening down positive symptoms like hallucinations and delusions, though they often cause significant motor side effects.

What are neural correlates in schizophrenia?

Neural correlates are patterns of structure or activity in the brain that occur in conjunction with specific symptoms. For example, enlarged ventricles (fluid-filled spaces) in the brain are often correlated with negative symptoms and a poor response to medication. This suggests that some aspects of schizophrenia are linked to physical brain damage or loss of tissue.

How can active learning help students understand biological therapies?

Active learning, such as modelling the synapse or debating drug types, helps students move beyond rote memorisation of drug names. When they have to explain the mechanism of a drug to a peer or defend its use in a debate, they develop a deeper understanding of how neurochemistry relates to behaviour. This makes their evaluative writing much more precise and evidence-based.