The biological approach to explaining and treating OCD

Question 1

What are the two explanations for OCD?

Answer 1

Genetic and neural

Question 2

What did genetic research originally centre on?

Answer 2

Twin and family studies

Question 3

What does genetic research rely on now?

Answer 3

DNA profiling and gene mapping

Question 4

What does the genetic explanation believe is the cause of OCD?

Answer 4

A combination of genes that makes some individuals more vulnerable to developing the disorder than others

Question 5

What was Grootheest et al.’s meta-analysis on?

Answer 5

70 years worth of twin studies

Question 6

What did Grootheest et al. find?

Answer 6

Genetic influences range from 45%-65% and OCD originating in childhood is linked to genetics more than OCD developing in adulthood

Question 7

Explain the neural explanation of OCD

Answer 7

Some forms of OCD are linked to breakdowns in immune system functioning, such as through streptococcal infections, Lyme’s disease and influenza, which damage neural connections

Question 8

What do PET scans show and what does this suggest?

Answer 8

Relatively low levels of serotonin activity is common in OCD sufferers, and as drugs that increase serotonin activity have been found to alleviate symptoms, it suggests that the neurotransmitter may be involved

Question 9

Where do PET scans show high levels of activity in OCD sufferers and what is this area associated with?

Answer 9

The orbital frontal cortex: A brain area associated with higher-level thought processes and the conversion of sensory information into thoughts. This area is also thought to initiate activity upon receiving impulses to act and then stopping the activity when the impulse lessens

Question 10

What did Pichichero report?

Answer 10

Children with streptococcal throat infections often displayed sudden indications of OCD symptoms shortly after becoming infected. These children also exhibited symptoms of Tourette’s syndrome, supporting the idea that such infections may be having an effect on neural mechanisms underpinning OCD

Question 11

What did Fallon and Nields find?

Answer 11

40% of people contracting Lyme’s disease incur neural damage resulting in psychiatric conditions including OCD

Question 12

What did a NIHM study find from DNA samples of OCD sufferers?

Answer 12

OCD is associated with two mutations of the human serotonin transporter gene which leads to diminished levels of serotonin

Question 13

What is the evolutionary explanation of OCD?

Answer 13

Behaviours such as washing and cleaning are useful against infection and therefore have a survival value that are chosen by natural selection

Question 14

What is the most common biological treatment of OCD?

Answer 14

Drugs, although psychosurgery is sometimes used as well

Question 15

What drug treatments are used to treat OCD?

Answer 15

Antidepressants such as SSRIs are used because they elevate levels of serotonin and cause the orbital frontal cortex to function at more normal levels

Question 16

What is the most common SSRI used with adults?

Answer 16

Prozac (Fluoxetine)

Question 17

How long does the drug treatment last?

Answer 17

Between 12 and 16 weeks

Question 18

What did Koran et al. find?

Answer 18

Administering multiple drug therapies at once has more effect than one drug treatment at a time, but SRI treatment did have some positive effect

Question 19

How many of Koran et al.’s participants experienced side-effects?

Answer 19

6/9 (60%)

Question 20

What did Pigot and Seay find in relation to side-effects?

Answer 20

Antidepressant drugs had serious side-effects

Question 21

What thoughts can increase as a side-effect of drug treatments?

Answer 21

Suicidal thoughts

Question 22

What is psychosurgery?

Answer 22

Involves destroying brain tissue to disrupt the cortico-striatal circuit using radio-frequency waves, which has an effect on the orbital frontal cortex, thalamus and the caudate nucleas brain areas

Question 23

How many of Richter’s patients had a 35% or more decrease in symptoms after psychosurgery? What side-effects did they have?

Answer 23

30%; Seizures and urinary incontinence

Question 24

What percentage of OCD patients get worse over time?

Answer 24

10%

Question 25

What type of therapy is habituation therapy and what does it involve?

Answer 25

CBT; Changing obsessional thinking by relieving obsessional thoughts repeatedly to reduce the anxiety they create, and are taught that intrusive thoughts are normal, and thinking about doing something isn’t the same as doing it

Question 26

What is the most successful treatment of OCD?

Answer 26

CBT; Although success rates are even higher when combined with drug treatments

Question 27

What did O’Kearney find?

Answer 27

CBT is effective at treating OCD in children and adolescents, but more so when combined with drug therapy

Question 28

CBT therapy is unsuitable for which patients, and which treatment is more effective with them?

Answer 28

Patients who don’t have the verbal skills to talk about their inner feelings, or perhaps do not want to; drug therapy is more suited to these patients

Question 29

What is the main flaw with drug treatments?

Answer 29

They do not “cure” OCD, they reduce anxiety and mask the symptoms

Question 30

What did Cromer find?

Answer 30

50% of OCD sufferers experienced a traumatic event

Question 31

What brain structures are associated with OCD?

Answer 31

Left hippocampal gyrus is associated with processing unpleasant emotions, functions abnormally in OCD sufferers (orbital frontal cortex)