Bio approach explaining OCD

Question 1

2 genetic explanations of OCD

Answer 1

COMT gene
SERT gene

Question 2

COMT gene

Answer 2

Produces dopamine (high levels in people with OCD)
Variation of COMT produces higher levels of dopamine
This gene more common in people with OCD

Question 3

SERT gene

Answer 3

Affects transmission of serotonin
Mutation in SERT gene = lower serotonin
Low levels of serotonin associated with OCD

Question 4

2 neural explanations of OCD

Answer 4

Serotonin and dopamine
Decision-making

Question 5

Serotonin + dopamine

Answer 5

High levels of dopamine associated with OCD
Animal study, gave animals high dose of drugs increasing level of dopamine, movements resembles compulsive behaviours

Serotonin - low levels associated with OCD
Gave antidepressants (increase serotonin production) decreased OCD symptoms

Question 6

Decision - making

Answer 6

Some OCD linked to impairing decision making
Associated with abnormal functioning of the lateral of frontal love (logical thinking + decision making) of brain

Question 7

AO3

Answer 7

Family studies
First degree relative with OCD - more likely to get OCD
5X greater risk
However: families share environment and genes
Environment may also affect

Psychological factors
Two-process model: OCD caused my association between neutral stimulus + anxiety
Maintained through operant: avoided thru compulsive behavior (washing hands)

Possessing COMT gene
Baby can be screened to see if they posses COMT gene
Gene therapy can “turn off” gene so OCD isn’t expressed
However causes ethical issues

Twin studies
Higher concordance rate for MZ than DZ twins
MZ twins 2x likely to develop OCD if co-twin had disorder
However never 100%