P - OCD and the biological approach

Question 1

Genetic explanation of OCD

Answer 1

• Lewis found that of his OCD patients 37% had parents with OCD and 21% had siblings with OCD. This suggests that genetic vulnerabilities can run in the family
• Candidate genes: (genes that are involved in the vulnerability for OCD) Some of these genes are involved in regulating the development of the serotonin system. For example, the gene 5HT1-D beta
• However, OCD is polygenic, this means that OCD is caused by several genes. It has been found that over 230 genes may be involved in OCD
• The origin of OCD has different causes; a group of genes that cause OCD in one person may not cause OCD in another person

Question 2

Neural explanation of OCD

Answer 2

• People with OCD may have low levels of serotonin which is believed to help regulate mood. Therefore, they may have abnormal transmission of mood relevant information
• Some research using PET scans has found that abnormalities in the basal ganglia in the brain may be linked to OCD. Max et al found increased rates of OCD in people after brain injuries that caused brain damage to the basal ganglia

Question 3

Evaluation of the genetic explanation of OCD

Answer 3

• Too many candidate genes; polygenic; psychologists have been much less successful at pinning down all the genes involved; this means the genetic explanation is unlikely to ever be very useful because it provides little predictive value
• Cromer et al found that over half the OCD patients in their sample had a traumatic event in their past, this suggests that OCD cannot be entirely genetic in origin. It may be more productive to work on the environmental causes

Question 4

Evaluation of the neutral explanation of OCD

Answer 4

• The serotonin link with OCD may simply just be co-morbidity; many people who have OCD become depressed so the low levels of serotonin may be because they are depressed rather than OCD

Question 5

Drug therapy for OCD

Answer 5

• SSRIs; increase levels of serotonin at the synapse by preventing reuptake (type of antidepressant)
• SSRIs are often used with CBT. The drugs reduce a patient’s emotional symptoms, such as feeling anxious or depressed. This means that patients can engage more effectively with CBT
• When SSRI’s don’t work; SNRI’s are used; increase levels of serotonin and noradrenaline

Question 6

Evaluation of drug therapy for OCD

Answer 6

• Cost-effective and non-disruptive compared to psychological therapies
• Drugs can have side-effects; some examples include: indigestion, blurred vision, loss of sex drive
• Doesn’t work for everyone
• Clear evidence for the effectiveness of SSRI’s in reducing the severity of OCD symptoms