Section 4 : Psychopathology - The Biological Apporach to OCD

Question 1

What does the biological approach assume

Answer 1

That psychological disorders are physical illnesses with physical causes. In principle they’re no different from physical illnesses like flu, except they have major psychological symptoms

Question 2

What are the biological explanations of OCD

Answer 2

• Genetic factors
• Biochemical factors
• Neurological factors

Question 3

What evidence is there for that genetics play a part in OCD

Answer 3

• Billet et al 1998
• Paul’s et al 2005

Question 4

What was Billet el al 1998 (for genetics factors play a part in OCD)

Answer 4

• Did a meta-analysis of twin studies that had been carried out over a long period of time
• they found that for identical twins, if one twin had OCD then 68% of the time both twins had it compared to 31% for non-identical twins

Question 5

What was Paul’s et al 2005 (for genetics factors play a part in OCD)

Answer 5

• found that 10% of people with an immediate relative with OCD also suffered from the disorder
• this is compared to around 2% of people in the general population

Question 6

What evidence is against genetic factors playing a part in OCD

Answer 6

• No study found a 100% concordance rate, so genetics can’t be the full story in OCD
• Possible that children imitate the obsessive and compulsive behaviour of their relatives
• Concordance rates don’t prove that OCD is caused by genetics
• It may be that general anxiety is genetic and that going on to develop OCD itself has other contributing factors e.g biochemical or psychological factors

Question 7

What do PET scans show in OCD sufferers

Answer 7

They show that levels of the neurotransmitter serotonin are lower in OCD sufferers

Question 8

What evidence is for biochemical factors play a part in OCD

Answer 8

• Insel 1991
• Zohar et al 1996

Question 9

What was found in Insel 1991

Answer 9

Found that a class of drugs called SSRI’s, which increase the levels of serotonin, can reduce symptoms of OCD in 50% to 60% of cases.

Question 10

What did find Zohar et al 1996

Answer 10

Found that SSRI’s alleviated symptoms in 60% of patients with OCD

Question 11

What evidence is there against biochemical factors playing a part in OCD

Answer 11

• SSRI’s appear to offer some relief to suffered of OCD. However as this is not true in 100% of cases, there must be more to understanding OCD
• The link with serotonin is correlational, so it doesn’t show cause and effect. It may be that decreased serotonin levels are a symptom of OCD rather than a cause of it

Question 12

Some, research using PET scans found….

Answer 12

That abnormality in the basal ganglia within the brain may be linked to OCD

Question 13

What evidence is in favour of neurological factors playing a part in OCD

Answer 13

• Max et al 1995
• Other researchers found increased activity in this area during OCD-related thoughts and behaviours
• OCD is often found in people with other diseases which involve the basal ganglia e.g. Parkinson’s and Huntington’s disease

Question 14

What did Max et al find

Answer 14

Found increased rates of OCD in people after head injuries that caused brain damage to the basal ganglia

Question 15

What evidence is there against neurological factors playing against a part in OCD

Answer 15

• Aylward et al didn’t find a significant difference in basal ganglia impairment between OCD patients and controls
• Basal ganglia damage hasn’t been found in 100% of people with OCD so it can’t be the full story

Question 16

What are the strength of the biological explanation of OCD

Answer 16

• Has a scientific basis in biology, there’s evidence that low serotonin and damage to the basal ganglia correlate with cases of OCD, though this doesn’t necessarily show a casual relationship
• twin studies shown that genetics have at least some effect on the likelihood of developing OCD
• can be seen as ethical - people aren’t blamed for their disorders; they just have an illness

Question 17

What are the weaknesses of biological explanations of OCD

Answer 17

• the explanation doesn’t take into account the effect of the environment, family, childhood experiences or social influence - psychologists taking other approaches consider these factors
• biological therapies raise ethical concerns. Drugs can produce addiction and may only suppress symptoms rather than cure the disorder

Question 18

What is the biological approach to treating OCD

Answer 18

The biological approach to treating OCD involves drug therapy

Question 19

What does SSRI’s stand for

Answer 19

Selective serotonin reuptake inhibitors

Question 20

What type of drug are SSRI’s

Answer 20

Antidepressant drug which increases the availability of serotonin

Question 21

How does drug therapy usually work

Answer 21

Increasing levels of serotonin in the brain using SSRI’s

Question 22

What do SSRI’s prevent

Answer 22

Prevents the reuptake of serotonin in the synaptic cleft (gap between two neurons). This means there’s more serotonin available to the next neuron

Question 23

What are the advantages of drug therapy

Answer 23

• Several researchers have found SSRI’s to be effective in treating OCD
• Thoren et al 1980 found that use of SSRI’s was significantly better at reducing obsessional thoughts than a placebo
• Research has found that using other antidepressants that don’t affect serotonin levels is ineffective at reducing OCD symptoms

Question 24

What are the disadvantages of OCD

Answer 24

• Up to 50% of patients with OCD don’t experience any improvement in their symptoms when taking SSRI’s
• out of those that do improve, 90% of them have a relapse when they stop taking them
• SSRI’s have to be taken for several weeks before the patient experiences an improvement in their symptoms
• Side effects of using these types of drugs include nausea and headaches and sometimes increased levels of anxiety. This can cause people to stop taking their medication