The biological approach to explaining OCD

Question 1

The COMT gene

Answer 1

Regulates the production of dopamine. This gene is more common in those with OCD.

Question 2

SERT gene

Answer 2

Affects the transport of serotonin.

Lower levels of serotonin are common in OCD.

Question 3

Diathesis stress

Answer 3

Genetic predisposition plus environmental factors = OCD

Question 4

Abnormal levels of neurotranmitters

Answer 4

Szechtman - high dopamine = compulsive behaviours in animals

Pigott = low level of serotonin = increase in OCD symptoms

Question 5

A03: Twin studies

Answer 5

Billet - Mz twins were more likely than DZ twins to both have OCD rather than just one as they share 100% of DNA.
However, not 100% which means there has to be some form of environmental stimulus

Question 6

A03: Other disorders

Answer 6

Tourette’s, OCD, Autism and Anorexia all share a gene. This means there is not one specific gene to OCD but instead there is a predisposition factor

Question 7

A03: Research support for genes and OFC

Answer 7

Menzies - found reduced grey matter in the OFC of OCD clients and family members of those clients. meaning there is a biological factor