Topic 8 - Evolutionary Psychiatry

Question 1

If evolution is true, why do mental disorders exist and persist?

Answer 1

1. Genes (heritability)
2. They are actually not disorders, but functional adaptations.

Question 2

What does it mean for a disorder to be polygenic?

Answer 2

It means that they can involve hundreds or thousands of genes.

Question 3

How do disorders arise despite natural selection?

Answer 3

Example: autism.
1. Mutations arise faster than natural selection can get rid of them.
2. Highly polygenic + heritability

Question 4

How do disorders arise because of natural selection?

Answer 4

Because they are actually adaptive behaviours, and the risk of becoming maladaptive is not too high.

Question 5

What could be an EP justification for depression symptoms?

Answer 5

Depressive symptoms may be brought on by an adaptation designed to promote analytical thinking. Therefore, they might be best treated by encouraging and promoting analysis instead of abolishing rumination.

Question 6

What is the smoke detector principle?

Answer 6

When the cost of expressing a defence is low compared to the potential harm it protects against, the optimal system will express many false alarms.

Question 7

What is the harm prevention model?

Answer 7

Certain behaviours (although maladaptive) can actually lead to certain benefits (ie. OCD).