Synaptic Plasticity and Schizophrenia

Question 1

How common is schziophrenia?

Answer 1

Scz affects 0.8% of the population wordwide with an equal sex ratio, although men typically develop it earlier and more severely.

Question 2

What is the normal age of onset for schizophrenia?

Answer 2

Normally starts when patients are in their 20s but this can range from 7-70.
It is commonly co-morbid, especially with substance abuse.
There is a substantial genetic component 65-80% heritability

Question 3

What is the course of recovery like in schizophrenia?

Answer 3

The course is variable with 20% recovering, 40% relapsing and 40% chronic.
This is important as schizophrenia increases mortality 3x, reducing life expectancy by 15-20 years.
Around 10% can be explained by suicide but natural causes are influenced as well.
Promisingly, 70% of patients respond to antipsychotic (neuroleptic) drugs - although these are specific to positive symptoms.

Question 4

What are the characteristics of schizophrenia?

Answer 4

Schizophrenia is characterised by positive (psychotic), negative and cognitive symptoms.
The key features of the positive symptoms are delusions which describe false beliefs (likely reflecting false associations)
These are held with complete conviction despite contrary evidence
Are not culutrally appropriate
Usually have personal significance
Often are persecutory or bizarre

Question 5

What are the dominant neurochemical theories of schizophrenia?

Answer 5

The Dopamine Hypothesis
The Glutamate Hypothesis
these are not mutually exclusive