Psychosis & Schizophrenia

Question 1

What is psychosis?

Answer 1

A mental condition characterised by hallucinations, delusions, disturbed thoughts, and lack of insight.

Question 2

What are the three main symptom categories of schizophrenia?

Answer 2

• Positive symptoms: Hallucinations, delusions, disorganised speech.
• Negative Symptoms: Apathy, reduced emotional expression, social withdrawal.
• Cognitive Symptoms: Impaired attention, working memory and executive function/

Question 3

What genetic factors are associated with schizophrenia? (2)

Answer 3

• Strong hereditary component: ~50% risk in monozygotic twins.
• Over 100 susceptibility genes identified, but no single causative gene.

Question 4

What are some environmental risk factors for schizophrenia? (4)

Answer 4

• Prenatal infections.
• Birth complications
• Urban upbringing
• Dysfunctional family environments

Question 5

What are the structural brain abnormalities seen in schizophrenia? (2)

Answer 5

• Loss of neuronal tissue.
• Enlarged ventricles.

Question 6

What functional brain abnormalities are linked to schizophrenia? (2)

Answer 6

• Abnormal prefrontal cortex activity.
• Reduced synaptic connectivity.

Question 7

How does the dopamine theory explain schizophrenia? (2)

Answer 7

• Hyperactivity of D2 receptors in the mesolimbic pathway: Positive Symptoms.
• Hypoactivity of D1 receptors in the prefrontal cortex: Negative and cognitive symptoms.

Question 8

What evidence supports the serotonin theory of schizophrenia? (2)

Answer 8

• 5HT2A receptor agonists (e.g., LSD) induce psychotic symptoms.
• 5HT2A antagonists alleviate symptoms.

Question 9

How does the glutamate theory explain schizophrenia? (2)

Answer 9

• Loss of cortical glutamate receptors
• NMDA receptor antagonists (e.g., ketamine) mimic psychotic symptoms.

Question 10

What are the kye differences between typical and atypical antipsychotics? (2)

Answer 10

• Typical antipsychotics: High affinity D2 antagonists, treat positive symptoms, but cause motor side effects.
• Atypical antipsychotics: Lower D2 affinity, higher 5HT2A antagonism, treat positive and negative symptoms with fewer motor side effects.

Question 11

Name two typical (first-generation) antipsychotics.

Answer 11

Chlorpromazine, Haloperidol.

Question 12

What are common side effects of typical antipsychotics? (2)

Answer 12

• Extrapyramidal effects (e.g., tardive dyskinesia, Parkinsonism).
• Hyperprolactinemia

Question 13

Name two atypical (second-generation) antipsychotics.

Answer 13

Clozapine, Olanzapine

Question 14

What are common side effects of atypical antipsychotics? (3)

Answer 14

• Weight gain (H1, 5HT2C antagonism).
• Diabetes
• Agranulocytosis (especially with Clozapine).

Question 15

What is Cobenfy, and why is it significant?

Answer 15

• A combination of Xanomeline (M1/M4 muscarinic antagonist) and Trospium.
• Approved in 2024 for positive and cognitive symptoms of schizophrenia

Question 16

How do nicotinic receptors relate to schizophrenia treatment? (2)

Answer 16

• High smoking prevalence in schizophrenia suggests nicotinic receptor involvement.
• Nicotinic agonists may enhance attention and sensory gating.

Question 17

What are emerging treatment targets in schizophrenia? (2)

Answer 17

• Nicotinic and muscarinic receptors.
• Glutamate modulation via NMDA receptors

Question 18

How do NMDA receptor antagonists like ketamine relate to schizophrenia?

Answer 18

They induce psychotic symptoms, supporting the glutamate theory of schizophrenia.

Question 19

Why are second-generation antipsychotics preferred over first-generation ones?

Answer 19

They treat both positive and negative symptoms and have fewer motor side effects.

Question 20

What role does dopamine play in schizophrenia’s positive and negative symptoms? (2)

Answer 20

• Positive Symptoms: Hyperactivity of D2 receptors in the mesolimbic pathway.
• Negative Symptoms: Hypoactivity of D1 receptors in the prefrontal cortex.