OCD

Question 1

what are obsessions?

Answer 1

recurring, intrusive thoughts e.g. deadly germs everywhere

Question 2

what are compulsions?

Answer 2

• uncontrollable urges to repetitively perform tasks and behaviours as a result of obsessions e.g. repetitively washing hands to get rid of germs
• only a temporary solution
• done to reduce anxiety

Question 3

what’s OCD?

Answer 3

• most people with OCD will have obsessions and compulsions
• most sufferers realise these are excessive but can’t control them, leading to higher levels of anxiety
• interferes with everyday activities
• 2% of the population suffer

Question 4

what are the behavioural characteristics of OCD?

Answer 4

• compulsions
• avoidance e.g. avoiding germs to reduce anxiety

Question 5

what are the emotional characteristics of OCD?

Answer 5

• anxiety and distress
• accompanying depression
• guilt and disgust

Question 6

what are the cognitive characteristics of OCD?

Answer 6

• obsessions
• catastrophic thoughts
• hypervigilance
• irrational beliefs

Question 7

what’s the biological approach to explaining OCD?

Answer 7

• genetic explanations
• neural explanations

Question 8

genetic explanations of OCD

Answer 8

• OCD is inherited through genetic transmission
• research centres on twin and family studies
• gene-mapping studies - comparing genetic material from sufferers and non-sufferers

Question 9

what are candidate genes?

Answer 9

• genes which create vulnerability for OCD
• some are involved in regulating the development of the serotonin system

Question 10

OCD is polygenic - why?

Answer 10

• means that it’s not caused by one single gene, several genes are involved
• Taylor (2013) has found evidence that up to 230 different genes are involved
• genes in relation to OCD include those associated with dopamine and serotonin

Question 11

what’s meant by aetiologically heterogenous?

Answer 11

one group of genes may cause OCD in one person but a different group may cause it in another person

Question 12

different types of OCD

Answer 12

there’s some evidence to suggest that different types of OCD may be the result of particular gene variations e.g. hoarding disorder and religious obsessions

Question 13

strength of the genetic explanation of OCD - supporting evidence

Answer 13

Lewis (1936)
- observed that 37% of his OCD patients had parents with OCD and 21% had siblings with OCD

Question 14

weakness of the genetic explanation of OCD - methodological problems

Answer 14

• studied through twin and family studies
• twins/siblings share the same environment as well as the same genes, so it’s difficult to determine whether nature or nurture causes OCD
• can’t account for cases where there’s no family history of OCD, so it’s a limited explanation

Question 15

strength of the genetic explanation of OCD - practical application of gene therapy

Answer 15

• moved away from using a candidate gene approach and has successfully associated distinct patterns of genetic mutations with OCD
• allows the targeting of specific genes to develop new gene-based treatments for OCD
• could improve the quality of life for OCD sufferers

Question 16

weakness of the genetic explanation of OCD - too many candidate genes

Answer 16

• twin studies strongly suggest that OCD is largely under genetic control
• however, pinning down all the genes has been less successful
• each genetic variation only increases the risk by a fraction
• the genetic explanation is unlikely to ever be useful

Question 17

what’s the neural explanation to OCD?

Answer 17

the genes associated with OCD are likely to affect the levels of key neurotransmitters as well as structures of the brain

Question 18

what’s the role of serotonin?

Answer 18

• serotonin is believed to help regulate mood
• neurotransmitters are responsible for relaying information from one neuron to another
• if an individual has low levels of serotonin, normal transmission of mood-relevant information doesn’t take place
• this might be linked to obsessive thoughts and anxiety
• PET scans have shown relatively low levels of serotonin activity in OCD patients

Question 19

decision-making systems

Answer 19

• the frontal lobe is thought to help initiate activity upon receiving impulses to act and then to stop the activity when the impulse lessens
• in non-sufferers, once the action has been done, the impulse to perform the activity stops and so does the behaviour
• however, sufferers may have difficulty switching off impulses so they turn into obsessions, resulting in compulsive behaviour

Question 20

role of the parahippocampal gyrus

Answer 20

there’s evidence to suggest that an area in the parahippocampal gyrus associated with processing unpleasant emotions functions abnormally in OCD sufferers

Question 21

role of the basal ganglia

Answer 21

hyperactivity in the basal ganglia may also be linked with compulsions

Question 22

strength of the neural explanation to OCD - supporting evidence

Answer 22

• some antidepressants work purely on the serotonin system, increasing levels of serotonin
• they’re effective in reducing OCD symptoms, suggesting that serotonin is involved in OCD

Question 23

strength of the neural explanation to OCD - supporting studies

Answer 23

Hu (2006)
- compared serotonin activity in 169 OCD sufferers and 253 non-sufferers
- found serotonin levels were lower in the OCD patients
- supports the idea that low levels of serotonin are associated with OCD

Question 24

weakness of the neural explanation to OCD - not all sufferers respond positively to serotonin enhancing drugs

Answer 24

• improvement rate from SSRIs (type of antidepressant) is only 50% so low serotonin can’t be the sole cause of OCD
• there’s likely to be another factor involved

Question 25

weakness of the neural explanation to OCD - biological reductionism

Answer 25

- OCD is a complex disorder being explained simply in terms of neurotransmitters and brain structures - it's likely that there's other environmental factors such as trauma that need to be considered - this explanation is therefore over simplistic and incomplete

Question 26

what's the biological approach to treating OCD?

Answer 26

drug therapy

Question 27

what does drug therapy involve?

Answer 27

- aims to increase / decrease levels of neurotransmitters in the brain or to increase / decrease their activity - low levels of serotonin are associated with OCD

Question 28

what are SSRIs?

Answer 28

- selective serotonin reuptake inhibitor - antidepressant drug that's used to tackle the symptoms of OCD - work on the serotonin system in the brain

Question 29

how do SSRIs work?

Answer 29

- serotonin is released by pre-synaptic neurons and travels across the synapse - the neurotransmitter chemically conveys the signal from the pre-synaptic neuron to the post-synaptic neuron - unused neurotransmitters are then reabsorbed by the pre-synaptic neuron to be re-used - SSRIs increase levels of serotonin in the synapse by preventing the re-absorption and breakdown - therefore, serotonin continues to stimulate the post-synaptic neuron

Question 30

SSRI dosage

Answer 30

- dosage varies according to which SSRI is prescribed - may be increased if it's not benefitting the patient - takes 3-4 months of daily use for it to have an impact

Question 31

combining SSRIs with other treatments

Answer 31

- drugs are often used alongside CBT to treat OCD - the drugs reduce emotional symptoms, enhancing engagement with CBT - occasionally, other drugs are prescribed alongside SSRIs

Question 32

alternatives to SSRIs

Answer 32

- if an SSRI isn't effective after 3-4 months, the dose can be increased - it can also be combined with another drug - sometimes different antidepressants are fried

Question 33

another type of antidepressant - tricyclics

Answer 33

- e.g. clomipramine - have the same effect as SSRIs - clomipramine has more severe side effects than SSRIs - generally reserved for those who don't respond to SSRIs

Question 34

another type of antidepressant - SNRIs

Answer 34

- serotonin-noradrenaline reuptake inhibitors - used to treat OCD in the last 5 years - for those who don't respond to SSRIs - SNRIs increase levels of serotonin and noradrenaline

Question 35

strength of drug therapy - evidence for effectiveness

Answer 35

Soomro et al (2008) - reviewed 17 studies of SSRIs vs placebo treatments involving 3097 patients - found SSRIs to be effective in the short term in treating OCD compared to those in the placebo conditions - effectiveness seems to be greatest when SSRIs are combined with CBT - typically, symptoms decline significantly for around 70% of patients taking SSRIs, and alternative treatments can be effective for the remaining 30%

Question 36

strength of drug therapy - cost effective and non disruptive

Answer 36

- cheap compared to psychological treatments - don't require a therapist - good value for the NHS - don't have to engage in the hard work of CBT

Question 37

weakness of drug therapy - side effects

Answer 37

- some suffer side effects including indigestion, blurred vision, and loss of sex drive - these side effects are usually temporary - for those taking clomipramine, side effects are more common and can be serious e.g. weight gain, disruption to blood pressure - this reduces effectiveness because people stop taking the medication

Question 38

weakness of drug therapy - some cases of OCD follow trauma

Answer 38

- OCD can have a range of other, non-biological causes - in some cases, it's a response to a traumatic event - may be inappropriate to treat these cases with drugs