OCD

Question 1

Define OCD.

Answer 1

Obsessive-compulsive disorder (OCD) is a condition characterised by obsessive and/or compulsive behaviour. Obsessions are cognitive whereas compulsions are behavioural.

Question 2

Give some behavioural characteristics of OCD.

Answer 2

The main behavioural component of OCD is compulsions.
Compulsions are repetitive behavioural responses intended to neutralise obsessions, often involving rigidly applied rules. Most OCD sufferers recognise their compulsions are unreasonable but believe something bad will happen if they do not complete the behaviour.

Question 3

Give an example of a compulsion.

Answer 3

ritualised hand washing.

Question 4

Give some emotional characteristics of OCD.

Answer 4

Obsessive thoughts often lead to anxiety, worry and distress. Obsessive thoughts are unpleasant and frightening. The urge to repeat a behaviour causes anxiety. OCD is often accompanied by depression. As well as anxiety and depression, OCD sometimes involves other negative emotions such as guilt or disgust.

Question 5

Give some cognitive characteristics of OCD.

Answer 5

Obsessive thoughts are a major cognitive feature of OCD. These thoughts dominate one’s thinking and are persistent and recurrent thoughts, images or beliefs entering their mind uninvited and cannot be removed. Obsessions can be temporarily relieved by completing compulsions. People with OCD are aware that their obsessions and compulsions are irrational. If this did not happen, this would be symptoms of a different mental disorder.

Question 6

Define polygenic.

Answer 6

When a condition is not caused by a single gene but by a combination of genetic variations.

Question 7

Outline the genetic explanation to explaining OCD

Answer 7

Some mental disorders appear to have a stronger biological component than others, and OCD is a good example of a condition that may be largely understood as biological in nature.
Genes are involved in individual vulnerability to OCD. For example, Lewis found that of his OCD patients, 37% had parents with OCD and 21% had siblings with OCD. This suggests that OCD runs in families although it is probably down to genetic vulnerability not the certainty of OCD.

Question 8

Explain candidate genes in the context of OCD and give an example.

Answer 8

Candidate genes
are genes which create vulnerability for OCD. Some of these genes are involved in regulating the development of the serotonin system. For example, the SERT gene appears to be mutated in individuals with OCD.

Question 9

Explain how the SERT gene leads to OCD.

Answer 9

The mutation causes an increase in transport proteins at a neuron’s membrane which leads to an increase in the reuptake of serotonin into the neuron which decreases the level of serotonin in the synapse.

Question 10

Explain how OCD is polygenic.

Answer 10

OCD seems to be polygenic (it is not caused by one single gene but by a combination of genetic variations that together significantly increase vulnerability). Taylor analysed findings of previous studies and found evidence of up to 230 different genes involved either OCD.

Question 11

How many (known) genes are involved in OCD?

Answer 11

230

Question 12

Give a strength of the genetic explanation of the biological approach to explaining OCD.

Answer 12

There is a strong evidence base from a variety of sources which suggests that some people are vulnerable to OCD as a result of their genetic make-up. One source of evidence is twin studies. For example, Gottesman found that identical twins showed a concordance rate of 87% for obsessive symptoms as opposed to 47% in MZ twins. This suggests that genetic factors must be involved.

Question 13

Give a limitation of the genetic explanation of the biological approach to explaining OCD.

Answer 13

There are also environmental risk factors. There is strong evidence for the idea that genetic variation can make a person more or less vulnerable to OCD. However, OCD does not appear to be entirely genetic in origin as otherwise, concordance rates among identical twins would be 100%. It seems that environmental risk factors can also trigger or increase the risk of developing OCD.

Question 14

Outline the neural explanation as part of the biological approach to explaining OCD.

Answer 14

Neural mechanisms refer to regions of the brain, structures such as neurons and the neurotransmitters involved in sending messages through the nervous system.
For example, the prefrontal cortex (PFC) is involved in decision making and the regulation of primitive aspects of our behaviour. An over active PFC, causes an exaggerated control of primal impulses. For example, after a visit to the bathroom, your primal instinct is to avoid germs and wash your hands. Once you have finished, you will go about your day and the PFC reduces in activation. If you have OCD, your PFC is over-activated which means the obsessions and compulsions continue leading you to wash your hands over and over again.

Question 15

Explain the role of neurotransmitters in the neural explanation of the biological approach to explaining OCD.

Answer 15

The neurotransmitter serotonin is believed to help regulate mood. Some cases of OCD can be explained by a reduction in the functioning of the serotonin system in the brain. Additionally, dopamine levels are abnormally high in individuals with OCD. Dopamine has been associated with concentration which may explain why individuals with OCD experience an inability to stop focusing on obsessive thoughts and behaviours.

Question 16

Give a strength of the neural explanation of the biological approach to explaining OCD.

Answer 16

One strength of the neural model of the OCD is the existence of supporting evidence, Antidepressants that work purely on serotonin are effective in reducing OCD symptoms and this therefore suggests that serotonin may be involved in OCD.

Question 17

Give a limitation of the neural explanation of the biological approach to explaining OCD. (co-morbidity)

Answer 17

One limitation is that the serotonin-OCD link may not be unique to OCD. Co-morbidity, when a patient suffers from two disorders at the same time, is a common issue in patients with OCD and they are usually diagnosed with depression. Depression disrupts serotonin as does OCD therefore the chemical imbalance found in oCD sufferers may be because of depression and not OCD. This limits the neural explanation for OCD as it fails to explain why the same chemical imbalance is found in both OCD and depression as they are two different disorders.

Question 18

Give a limitation of the neural explanation of the biological approach to explaining OCD. (correlation and causality)

Answer 18

There is evidence to show that neurall systems do not work normally in people with OCD. However, this is simply a correlation between neural abnormality snd OCD and this does not explain the cause of OCD. It is quite possible that the OCD is influenced by a third factor.

Question 19

How does drug therapy decrease OCD symptoms?

Answer 19

Aims to increase or decrease levels of neurotransmitters in the brain or to increase/decrease their activity.

Question 20

Outline the role of SSRI’s.

Answer 20

SSRI’s are a type of antidepressant which work on the serotonin system in the brain. When serotonin is released from the pre-synaptic membrane into the synapse, it travels to the receptor sites on the post-synaptic neuron. Serotonin which is not absorbed is reabsorbed into the pre-synaprtic neuron. SSRI’s increase the level of serotonin in the synapse by preventing it from being reabsorbed. This increased level of serotonin results in more serotonin being received by the post-synaptic membrane. Dosage varies by which SSRI is being provided. SSRI;s are available as capsules or a liquid.

Question 21

What are SSRI’s full name?

Answer 21

Selective serotonin re-uptake inhibitors.

Question 22

What are tricyclics?

Answer 22

This acts on various systems including the serotonin system where it has the same effect as SSRI’s. They have more serious side effects than SSRI’s.

Question 23

Why would tricyclics be used?

Answer 23

When an individual does not respond to SSRI’s.

Question 24

What are SNRI’s?

Answer 24

These have been more recently used to treat OCD. They are said to be more effective as two neurotransmitters are affected- noradrenaline and serotonin.

Question 25

What are SNRI’s full name?

Answer 25

Serotonin-noradrenaline reuptake inhibitors.

Question 26

Why can it be important to combine the use of drug treatments and therapy to treat OCD?

Answer 26

The drugs reduce a person’s emotional symptoms which means that people can engage more effectively with the CBT.

Question 27

Give a strength of the biological approach to treating OCD. (evidence of effectiveness)

Answer 27

One strength of drug treatments for OCD is that there is evidence for its effectiveness. There is clear evidence to show that SSRI’s reduce symptom severity and improve the quality of life for people with OCD. For example, Soomro reviewed 17 studies that compared SSRI’s to placebos in the treatment of OCD. All 17 studies showed significantly better outcomes for SSRI’s than placebos. Typically symptoms reduced by around 70% and the remaining 30% can be helped by another alternative drug or psychological therapy. This means that drugs are helpful for most people with OCD.

Question 28

Give a strength of the biological approach to treating OCD. (cost-effective)

Answer 28

Another strength of drugs is that they are cost-effective. They are relatively cheap compared to psychological treatments because many thousands of tablets or liquids can be manufactured in the time it takes for a psychological therapy session to be completed. Using drugs to treat OCD is therefore goof value for public health systems like the NHS.

Question 29

Give a strength of the biological approach to treating OCD. (non-disruptive).

Answer 29

As compared to psychological therapies, SSRI’s are non disruptive. If you wish you can simply take drugs until your symptoms decline. This is different from therapy which involved time spent attending sessions. Also, therapies require a patient to be motivated whereas drugs do not. This means that drugs are popular with many people with OCD and their doctors as they are more likely to benefit those experiencing intense symptoms.

Question 30

Give a limitation of the biological approach to treating OCD. (serious side effects).

Answer 30

One limitation of drug treatments for OCD is that drugs can have potentially serious side-effects. A small minority of those who use SSRI’s will experience no benefit. Some people will experience indigestion, blurred vision and loss of sex drive. These side effects can be quite distressing. For those taking the tricyclic clomipramine, side effects are more common and can be more serious such as erection problems, weight gain and heart problems. This means that some people have a reduced quality of life as a result of taking drugs which may stop them taking the drugs all together.

Question 31

Give a limitation of the biological approach to treating OCD. (Drug therapy may not be the most effective treatment).

Answer 31

There is some evidence to suggest that even if drug treatments are helpful for people with OCD, they may not be the most effective treatments available. For example, Skapinakis carried out a systematic review of outcome studies and concluded that exposure therapies were more effective than SSRI’s in the treatment of OCD.