Explaining OCD - AO1

Question 1

What did Lewis (1936) find out and what does this suggest?

Answer 1

Observed that of his OCD patients 37% had parents with OCD and 21% had siblings with OCD

• This suggests that OCD runs in families
• Genetic vulnerability is passed from one generation to another

Question 2

What is the diathesis stress model?

Answer 2

Certain genes leave some people more likely to develop a mental disorder but it is not certain.
Some environmental stress (experience) is necessary to trigger the condition

Question 3

What are candidate genes?

Answer 3

Genes that create vulnerability for OCD. For example, the gene 5HT1 - D beta is implicated in the transport of serotonin across synpases

Question 4

What does polygenic mean?

Answer 4

Not caused by one single gene but by a combination of genetic variations that together increase vulnerability

Question 5

What did Taylor (2013) do?

Answer 5

Analysed findings of previous studies and found evidence that up to 230 different genes may be involved in OCD

Question 6

What does aetiologically heterogenous mean?

Answer 6

Origins vary from person to person

• A group of genes may cause OCD in one person but a different set may cause OCD in another

Question 7

What are neural explanations?

Answer 7

Genes associated with OCD are likely to affect the levels of neurotransmitters as well as structure in the brain

Question 8

What happens if a person has low levels of serotonin?

Answer 8

Normal transmission of mood relevant information cannot take place, as serotonin helps regulate mood, and a person may experience low moods

Question 9

What is abnormal decison making associated with?

Answer 9

The abnormal functioning of the frontal lobes of the brain
The frontal lobe is responsible for logical thinking and making decisions

Question 10

What is the function of the parahippocampal gyrus?

Answer 10

Associated with processing unpleasant emotions

• evidence suggests it functions abnormally in OCD