Biological Approach To Explaining OCD

Question 1

2 key assumptions of the biological approach

Answer 1

1. Suggests OCD is inherited and that individuals receive specific genes from their parents which influence the onset of OCD
2. Suggests that abnormal levels of neurotransmitters and certain regions of the brain are implicated in OCD

Question 2

What are the two explainations for OCD

Answer 2

1. Genetic explanations
2. Neural explanations

Question 3

What type of condition is OCD

Answer 3

-Polygenic, meaning several genes are involved
- suggested to be around 230 genes

Question 4

What type of gene is involved with OCD

Answer 4

Candidate genes - meaning OCD is likely to be inherited

Question 5

What is the COMT gene responsible for

Answer 5

• For the production of an enzyme called COMT, which regulates levels of the neurotransmitter, dopamine
• the abnormal “low activity” variant of this gene produces an insufficient amount of COMT, causing an inability to regulate dopamine levels

Question 6

What is dopamine responsible for

Answer 6

The organisation of thoughts in the pre frontal cortex and the pleasure reward pathway

Question 7

What does the production of high levels of dopamine cause

Answer 7

Symptoms of OCD - behavioural
- pleasure of completing the compulsion to reduce cognitions/emotions

Question 8

What is the SERT gene responsible for

Answer 8

• responsible for influencing transportation of the neurotransmitter serotonin
• mutation of this gene affects the transportation of serotonin between neurons by creating abnormally low levels of this neurotransmitter

Question 9

What is serotonin responsible for ?

Answer 9

Mood and anxiety levels

Question 10

What have low levels of serotonin been linked to ?

Answer 10

-OCD symptoms - emotion: communication errors and anxiety
- cognitive: hyper awareness of environment resulting in rituals

Question 11

Strength: supporting evidence

Answer 11

I: supporting evidence for the genetic biological explaination
E: a perosn with a family member diagnosed with OCD is around 4 times as likely to develop OCD compared to someone without it
Meta analysis of 14 twin studies - the concordance rates were twice as high for monozygotic twins rather than dizygotic twins
C: means genetic factors are a valid explanation of OCD, showing it is inherited

Question 12

Weakness: limitations

Answer 12

I: limitations of the genetic biological explanation
E: concordance rates from twin studies are never 100% and they should be if OCD were genetic in origin
High concordance rates in monozygotic twins could be explained through shared environmental experiences which are likely to be far more similar than dizygotic twins
C: means genetic explanation is incomplete

Question 13

Explain dopamine levels in neurochemistry

Answer 13

• OCD could be caused by abnormally high levels of dopamine
• giving dopamine enhancing drugs to animals results in movements that resemble compulsions
• excitatory neurotransmitter so increased levels influences concentration and creates inahibility to stop focusing on obsessive thoughts and repetitive behaviours

Question 14

Explain neural explainations for serotonin

Answer 14

• OCD caused by abnormally low levels of serotonin
• based on fact anti-depressant drugs that increase serotonin activity reduce OCD symptoms
• inhibitory neurotransmitter, so decreased levels of it mean repetitive behaviours/thoughts are not being switched off as normal;

Question 15

What region of the brain is involved with decision making

Answer 15

Pre-frontal cortex

Question 16

What does an overactive PFC cause

Answer 16

Causes OCD as it creates an exaggerated control of primal impulses

Question 17

Strength: supporting

Answer 17

I: supporting evidence for NEURAL biological explanations
E: OCD sufferers were found to have low levels of serotonin
Symptoms improved through the use of SSSRI’s showing imbalance could cause thee symptoms
Individuals with a damaged basal ganglia had a higher risk of developing OCD
C: biological factors are a valid explanation of OCD, showing its due to neural activity

Question 18

Weakness: limitations

Answer 18

I: limitations of the neural biological explanations of OCD
E: not all OCD sufferers symptoms will be reduced through the use of ant-depresssants showing its not an imbalance;ance of neurotransmitters causing the symptoms
OCD often linked with trauma related disorder. Ppl with PTSD are 3-4 times more likely to be diagnosed with OCD
C: means the neural explanation will be incomplete

Question 19

Weakness: reductionist

Answer 19

I: biological explanations for OCD are reductionist
E: reduce OCD to a basic level of single constituent component part, Eg: stating it is caused by abnormally low levels genes or neurotransmitters
Overlook more holistic explanations such as environmental or societal