The Biological Approach To Explaining And Treating OCD

Question 1

What are the 2 explanations of OCD?

Answer 1

Genetic explanations
Neural explanations

Question 2

What is the diathesis-stress model? (OCD)

Answer 2

It suggests that certain genes may make people more vulnerable to OCD, but it is not certain - some environmental stress is needed to trigger the condition

Question 3

What is the candidate gene: SERT gene?

Answer 3

A mutation of the gene causes lower levels of serotonin

Question 4

What is the candidate gene: COMT gene?

Answer 4

A mutation of the gene causes higher levels of dopamine

Question 5

Why does OCD seem to be polygenic?

Answer 5

Evidence has shown that up to 230 different genes may be involved in OCD

Question 6

Which study provides evidence for the genetic explanation of OCD?

Answer 6

Nestadt et al (2010) - Review of twin studies

Question 7

What were the concordance rates of Nestadt et al’s study?

Answer 7

MZ twins - 68%
DZ twins - 31%

Question 8

What is a limitation of Nestadt et al.’s findings? (Concordance)

Answer 8

Results for MZ twins are not 100% concordant - if it was truly genetic, they would be 100% concordant

Question 9

What’s a strength of Nestadt et al.’s study?

Answer 9

Reliable - reviewed a large amount of data

Question 10

What does serotonin do?

Answer 10

Regulates mood and is a neurotransmitter

Question 11

What are neurotransmitters responsible for?

Answer 11

Relaying information from one neuron to another

Question 12

What do low levels of serotonin lead to?

Answer 12

Impaired transmission of mood-relevant information, leading to a lowered mood

Question 13

What are low levels of serotonin also linked to?

Answer 13

Obsessive thoughts

Question 14

What does abnormal frontal lobe functioning lead to?

Answer 14

Impaired decision-making, leading to symptoms of OCD

Question 15

What is a strength of neural explanations for OCD?

Answer 15

Supporting evidence from antidepressant studies shows that increasing serotonin levels reduces OCD symptoms, suggesting serotonin has a role in the development of OCD

Question 16

What is a limitation of the neural explanation for OCD?

Answer 16

Lack of understanding of what neural mechanisms are involved - incomplete explanation

Question 17

How is OCD treated?

Answer 17

Through drug treatment which aims to alter levels or activity of certain neurotransmitters

Question 18

What are drug treatments often used in conjunction with?

Answer 18

CBT

Question 19

What are SSRIs?

Answer 19

Selective Serotonin Re-uptake Inhibitors - the most commonly used drug for OCD (and depression)

Question 20

How do SSRIs work?

Answer 20

They prevent the reuptake of serotonin in the synaptic cleft. This means there’s more serotonin for the next neuron

Question 21

How long does it take for the benefits of SSRIs to show?

Answer 21

Around 3-4 months

Question 22

What are SNRIs?

Answer 22

Serotonin-noradrenaline reuptake inhibitors - an alternative for people who don’t respond to SSRIs

Question 23

What are tricyclics?

Answer 23

An older type of antidepressants that are similar to SSRIs but have worse side effects. Often a last resort nowadays.

Question 24

Which study supports drug therapy for OCD?

Answer 24

Soomro et al.

Question 25

What did Soomro et al. find?

Answer 25

That symptoms of OCD reduce for approx 70% of patients when taking SSRIs. (Which were more effective than placebos)

Question 26

What’s a strength of drug therapy for OCD?

Answer 26

It is easy and non-disruptive - patients just take a pill & don’t have to go to lengthy therapy sessions - more accessible to more people

Question 27

What is a limitation of drug therapy for OCD?

Answer 27

Drugs can have side effects (e.g. nausea, headaches, loss of sex drive) - patients less willing to take the drugs - symptoms will return