PsychoPathology

We define many aspects of what is normal by referring to typical values. Statistics inform us about things such as what age is most typical for women to have their first baby, the average shoe size for a ten year old etc... If we can define what is most common or normal, then we also have an idea of what is not common, i.e. abnormal.

Evaluation:

- The main issue is that there are many abnormal behaviours that are actually quite desirable. For example, very few people have an IQ over 150 but this abnormality is desirable. Equally there are some 'normal' behaviours that are undesirable. Experiencing depression, for example. is relatively common.Therefore, using statistical infrequency to define abnormality means that we are unable to distinguish between desirable and undesirable behaviours.

- The fact that cut-off points are subjectively determined is a limitation. If abnormality is defined in terms of statistical infrequency, we need to decide where to separate normal from abnormal. For example, one of the symptoms of depression is 'difficulty sleeping'. Some people might think abnormal sleep is less than 6 hours a night on average, others might think its 5. Such disagreements mean it is difficult to define in terms of Statistical Infrequency.

- In some situations it is appropriate to use a statistical criterion to define abnormality. For example, intellectual disability is defined in terms of the normal distribution using the concept of standard deviation to establish a cut-off point for abnormality. Any individual whose IQ is more than two standard deviations below the mean is judged as having a mental disorder - however such a diagnosis is only made in conjunction with failure to function adequately. This suggests that statistical Infrequency is only one of a number of tools.

- An issue is that behaviours that are statistically infrequent in one culture may be statistically more frequent in another. For example, one of the symptoms of schizophrenia is claiming to hear voices. However, this is an experience that is common in some cultures. What this means in practice is that there are no universal standards or rules for labelling a behaviour as abnormal.

These norms are created by a group of people and thus are 'social'. In any society there are standards of acceptable behaviour that are set by the social group, and adhered to by those socialised into that group. Anyone who behaves differently from these is classed as abnormal. Some rules about unacceptable behaviour are implicit whereas others are policed by laws. For example, not laughing at a funeral is an implicit social rule whereas causing a disrder in public is both a deviation from social norms and against the law.

Evaluation:

- What is socially acceptable now may not have been socially acceptable 50 years ago. i.e.50 years ago in Russia, anyone who disagreed with the state ran the risk of being regarded as insane and placed in a mental institution. Therefore if we define abnormality in terms of deviation from social norms, there is a real danger of creating definitions based on prevailing social morals and attitudes.

- Judgements on deviance relate to the context. For example, a person on the beach wearing a bikini is normal but if you wore that same outfit to work you would be regarded as abnormal and possibly be regarded as mentally ill. This means that social deviance on its own cannot offer a complete definition of abnormality, because it is inevitably related to both context and degree.

- On the positive side, this definition does distinguish between desirable and undesirable behaviour, a feature that was absent from the statistical infrequency model. The social deviancy model also takes into account the effect that behaviour had on others. Deviance is defined in terms of transgression of social rules and social rules are established in order to help people live together. According to this definition, abnormal behaviour is behaviour that damages others. This definition, therefore, offers a practical and useful way of identifying undesirable and potentially damaging behaviour, which may alert others to the need to secure help for the person connected.

From an individual's point of view, abnormality can be judged in terms of not being able to cope with everyday living, i.e. a failure to function adequately. So the functioning refers to everyday living, such as regular eating, washing clothes etc... Not functioning adequately causes distress for the individual and may distress others. Important to include 'distress to others', because, in the case of some mental disorders, the individual may not be distressed at all. People with Schizophrenia generally lack awareness that anything is wrong but their behaviour may be distressing to others. There may be situations where a person is not coping with everyday life in a 'normal' way - for example, a person may be content living in unwashed clothes. If this doesn't cause distress to self or others and then a judgement of abnormality is inappropriate.

Evaluation:

- Who is the person who decides if someone is failing to function adequately? If a person is experiencing personal distress, for example is unable to get to work or eat regular meals, they may recognise that as undesirable and may seek help. On the other hand, the individual may be quite content with the situation and/or simply unaware that they are not coping.Therefore, the limitation of this approach is that the judgement depends on who is making the decision,i.e. it is subjective.

- Another limitation is that some apparently dysfunctional behaviour can actually be adaptive and functional for the individual. For example, some mental disorders, such as eating disorders or depression, may lead to extra attention for the individual. Such attention is rewarding and thus quite functional rather than dysfunctional.This failure to distinguish between functional and dysfunctional behaviours means that this definition is incomplete.

- On the positive side, this definition of abnormality does recognise the subjective experience of the patient. It allows us to view mental disorder from the point of view of the person experiencing it. In addition, 'failure to function' is also relatively easy to judge objectively because we can list behaviours and thus judge abnormality objectively. This definition of abnormality therefore has a certain sensitivity and practicality.

Marie Jahoda pointed out that we define physical illness in part by looking at the absence of signs of physical health. Physical health is indicated by having correct body temperature, normal blood pressure etc... So the absence of these indicated illness. Jahoda suggested we should do the same for mental illness.Jahoda conducted a review of what others had written about good mental health. These are the characteristics that enable an individual to feel happy. Six categories - Self-attitudes: having high self-esteem and a strong sense of identity. - Personal growth and Self-actualisation: the extent to which an individual develops their full capabilities. - Integration, such as being able to cope with stressful situations. - Autonomy: being independent and self-regulating - Having an accurate perception of reality. - Mastery of the environment: including the ability to love, function at work and in interpersonal relationships, adjust to new situations and solve problems. The deviation from ideal mental health definition proposes that the absence of these criteria indicates abnormality, and potential mental disorder.

Evaluation:

- One of the major criticisms of this definition is that, according to ideal mental health criteria, most of us are abnormal. Jahoda presented them as ideal criteria and they certainly are. We also have to ask how many need to be lacking before a person would be judged as abnormal. Furthermore, the criteria are quite difficult to measure. This means that this approach may be an interesting concept but not really useable when it comes to identifying abnormality.

- Another limitation of this definition is that it tries to apply the principles of physical health to mental health. In general, physical illnesses have physical causes such as a virus or bacterial infection, and as a result this makes them relatively easy to detect and diagnose. It is possible that some mental disorders also have physical causes but many do not.Therefore, it is unlikely that we could diagnose mental abnormality in the same way that we can diagnose physical abnormality.

- This definition focuses on the positives rather than the negatives. It offers an alternative perspective on mental disorder that focuses on the 'ideal' - what is desirable rather than what is undesirable. Even though Jahoda's ideas have had some influence and are in accord with the 'positive psychology' movement. A strength of this approach, therefore lies in its positive outlook and its influence on humanistic approaches.

Phobic disorders are included in diagnostic manuals within the category of 'anxiety disorders', a group of mental disorders that share the same primary symptom of extreme anxiety. Phobic disorders, are instances of irrational fears that produce a conscious avoidance of the feared object or situation. This includes agoraphobia, social phobia and specific phobias.

Emotional Characteristics - The primary emotional characteristic of a phobia is fear that is marked and persistent, and is likely to be excessive and unreasonable. Coupled with fear are feelings of anxiety and panic. These emotions are cued by the presence or anticipation of a specific object or situation and are out of proportion to the actual danger posed.

Behavioural Characteristics - Obvious is avoidance. When a person with a phobia is faced with the object or situation that creates fear the immediate response is to try to avoid it. However, there is also the opposite behavioural response, which is to freeze or faint. Fight, Flight or Freeze. 'Freezing' is an adaptive response because a predator may think the prey is dead. Avoidance in the feared situation inteferes significantly with the person's normal routine.

Cognitive Characteristics - Relate to thought processes. In the case of phobias, a defining characteristic is the irrational nature of the person's thinking and the resistance to rational arguments. A further defining characteristic is that the person recognises that their fear is excessive or unreasonable, although this feature may be absent in children.

Depression is classified as a mood disorder. DSM-V distinguishes between major depressive disorder and persistent depressive disorder which is longer term and/or recurring.

Emotional Characteristics - A formal diagnosis of 'major depressive disorder' requires the presence of at least five symptoms and must include either sadness or loss of interest and pleasure in normal activities. Sadness is the most common description people give of their depressed state, along with feeling empty. Associated with this, people may feel worthless, hopeless and/or experience low self-esteem - all negative emotions. Loss of interest and pleasure in usual hobbies and activities is associated with feelings of despair and lack of control.

Behavioural Characteristics - In most patients there is a shift in activity level - either reduced or increased. Many depressed individuals experience reduced energy, a sense of tiredness and a wish to sleep all of the time. However, some become increasingly agitated and restless, and may pace around the room, wiring their hands or tear at their skin. Sleep may be affected; some people sleep much more whereas others find it difficult to sleep and experience insomnia. Appetite may also be affected; again there is a variation in this where some people have a reduced appetite where others eat considerably more than usual.

Cognitive Characteristics - The negative emotions related to depression are associated with negative thoughts, such as a negative self-concept as well as guilt, a sense of worthlessness and so on. Depressed people often have a negative view of the world and expect things to turn out badly rather than well. In general such negative thoughts are irrational;i.e. they do not accurately reflect reality.

Obsessive-Compulsive disorder is also classed as an anxiety disorder. The disorder typically begins in young adult life and has two main components - obsessions and compulsions. Obsessions are persistent thoughts and compulsions are repetitive behaviours.

Emotional Characteristics - Both the obsessions and compulsions are a source of considerable anxiety and distress. Sufferers are aware that their behaviour is excessive and this causes feelings of embarrassment and shame. A common obsession concerns germs which gives rise to feelings of disgust.

Cognitive Characteristics - Obsessions are recurrent, instrusive thoughts or impulses that are perceived as inappropriate or forbidden. They may be frightening and/or embarrasing so that the person doesn't want to share them with others. Common obsessional themes include ideas , doubts, impulses or images.They are seen as uncontrollable, which creates anxiety. The person recognises that the obsessional thoughts or impulses are a product of their own mind. At some point during the course of the disorder, the person does recognise that the obsessions or compulsions are excessive or unreasonable.

Behavioural Characteristics - Compulsive behaviours are performed to reduce the anxiety created by obsessions. They are repetitive and unconcealed, such as hand washing or checking. They may be mental acts such as praying or counting. Patients feel they must perform these actions, i.e. they are compelled to perform these actions otherwise something dreadful might happen. This creates anxiety. The behaviours are not connected in a realistic way with what they are designed to neutralise or prevent and are clearly excessive.

Orval Hobart Mowrer - Proposed the Two-Process Model to explain how phobias are developed.

Classical Conditioning: Initiation - A phobia is acquired through association - the association between a neutral stimulus, such as a white rat and a loud noise results in a new stimulus response being learned. The same steps can explain how a person might develop a fear of social situations after having a panic attack in such a situation.

Operant Conditioning: Maintenance - Through Classical Conditioning a phobia is acquired. However, this does not explain why individuals continue to feel fearful, nor does it explain why individuals avoid the feared object. The next step involves Operant Conditioning - the likelihood of a behaviour being repeated is increased if the outcome is rewarding. In the case of a phobia, the avoidance of the phobic stimulus reduces fear and is thus reinforcing. This is an example of negative reinforcement. The individual avoids the anxiety created by, for example, the dog or social situation by avoiding them entirely.

Social Learning - Social Learning theory is not part of the two-process model but it is a neo-behaviourist explanation, i.e. the fear seems reduced. Phobias may also be acquired through modelling the behaviour of others. For example, seeing a parent respond to a spider with extreme fear may lead a child to acquire a similar behaviour because the behaviour appears rewarding. 

Evaluation:

- The two-process model is supported by research asking people about their phobias. People with phobias often do recall a specific incident when their phobia appeared. However, not everyone who has a phobia can recall such an incident. Sue et al suggest that different phobias may be the result of different processes. For example, agoraphobics were most likely to explain their disorder in terms of a specific incident, whereas arachnophobics were most likely to cite modelling as the cause. This demonstrates the role of classical conditioning in developing phobias, but other processes may be involved in their maintenance.

- If a neutral stimulus becomes associated with a fearful experience the result should be a phobia, but this doesn't always happen. Research has found, for example, that not everyone who is bitten by a dog develops a phobia of dogs. This could be explained by the diathesis-stress model. This proposes that we inherit a genetic vulnerability for developing mental disorders. However, a disorder will only manifest itself if triggered by a life event, such as being bitten by a dog. This suggests that a dog bite would only lead to a phobia in those people with such a vulnerability. Therefore, the behavioural explanation is incomplete on its own.

- An experiment by Bandura and Rosenthal supported the social learning explanation. In the experiment a model acted as if he was in pain every time a buzzer sounded. Later on, those participants who had observed this showed an emotional reaction to the buzzer, demonstrating an acquired 'fear' response. This demonstrates that modelling the behaviour of others can lead to the acquisition of phobias.

Alternative method for treating phobias. The person with the phobia is immersed in the experience in one long session, experiencing their phobia at its worst. The session continues until the patient's anxiety has disappeared. The person with the phobia remains in position until they have become calm. The procedure can be conducted in vivo or virtual reality can be used.

Rationale - A person's fear response has a time limit. As adrenaline levels naturally decrease, a new stimulus-response link can be learned - the feared stimulus is now associated with a non-anxious response.

Evaluation:

- Flooding can be an effective treatment for those who stick with it and it is relatively quick. For example Choy et al reported that both SD and flooding were effective but flooding was the more effective of the two at treating phobias. On the other hand, another review concluded that SD and flooding were equally effective in the treatment of phobias. This shows that flooding is an effective therapy, albeit just one of several options.

- Flooding is not for every patient. It can be highly traumatic. Patients are made aware of this beforehand but, even then, they may quit during the treatment, which reduces the ultimate effectiveness of the therapy for some people. Individual differences in responding to flooding therefore limit the effectiveness of the therapy.

Joseph Wolpe developed a technique where phobics were introduced to the feared stimulus gradually.

Counterconditioning: - Basis of therapy, because patient is taught a new association that runs counter to the original association. Patient is taught, through CC, to associate phobic stimulus with a new response, i.e. relaxation instead of fear. In this way their anxiety is reduced - they are desensitised. 

Relaxation - First thing is relaxation techniques. Can be acheived by the patient is focusing on their breathing and taking slow, deep breaths. Progressive muscle relaxation is also used where one muscle at a time is relaxed.

Desensitisation hierarchy - SD works by gradually introducing the person to the feared situation one step at a time so it is not as overwhelming. At each stage the patient practises relaxation so the situation becomes more familiar, less overwhelming and their anxiety diminishes.

Evaluation:

- Research has found that SD is successful for a range of phobias. For example, McGrath et al. reported that about 75% of patients with phobias respond to SD. The key to success appears to lie with actual contact with the feared stimulus, so in vivo techniques are more successful than ones just using pictures or imagining the feared stimulus. Often a number of different exposure techniques are involved - in vivo, in vitro and also modelling, where the patient watches someone else who is coping well with the feared stimulus. This demonstrates the effectiveness of SD, but also the value of using a range of different exposure techniques.

- SD may not be effective against all phobias. Ohman et al suggest that SD may not be as effective in treating phobias that have an underlying evolutionary survival component, than in treating phobias which have been acquired as a result of personal experience. This suggests that SD can only be used effectively in tackling some phobias.

Systematic Desensitisation

Step 1: - Patient is taught how to relax their muscles completely.

Step 2: - Therapist and patient together construct a desensitisation hierarchy - a series of imagined scenes, each one causing a little more anxiety than the previous one.

Step 3: - Patient gradually works his/her was through desensitisation hierarchy, visualising each anxiety-evoking event while engaging in the competing relaxation response.

Step 4: - Once the patient has mastered one step in the hierarchy, they are ready to move onto the next.

Step 5: - Patient eventually masters the feared situation that caused them to seek help in the first place. 

Flooding

Step 1: - Patient is taught how to relax their muscles completely.

Step 2: - Patient masters the feared situation that caused them to seek help in the first place. This is accomplished in one long session.

Evaluation:

- Behavioural therapies for dealing with phobias are generally relatively faster, cheaper and require less effort on the patient's part than other psychotherapies. For example, CBT requires a willingness for people to think deeply about their mental problems, which is not true for behavioural therapies. This lack of 'thinking' means that the technique is also useful for people who lack insight into their motivations or emotions, such as children or patients with learning difficulties. A further strength of behavioural therapy is that it can be self-administered - a method that has proved successful with, for example, social phobia. These benefits were confirmed in the study described in ' Research Methods', which also found that self-administered therapy was as effective as therapist-guided therapy.

- It may be that the success of both SD and flooding is more to do with exposure to the feared situation than relaxation. It might also be that the expectation of being able to cope with the feared stimulus is most important. For example, Klein et al compared SD with supportive psychotherapy for patients with either social or specific phobias. They found no difference in effectiveness, suggesting that the 'active ingredient' in SD or flooding may simply be the generation of hopeful expectancies that the phobia can be overcome. This suggests that cognitive factors are more important than the behavioural approach generally acknowledges.

- Behavioural therapies may not work with certain phobias because the symptoms are only the tip of the iceberg. If the symptoms are removed the cause still remains, and the symptoms will simply resurface, possibly in another form. For example, according to the psychodynamic approach phobias develop because of projection. Freud recorded the case of Little Hans who developed a phobia of horses. The boy's actual problem was an intense envy of his father, but he could not express this directly and his anxiety was projected onto the horse. The phobia was cured when he accepted his feelings about his father. This demonstrates the importance of treating the underlying causes of a phobia rather than just the symptoms.

Albert Ellis proposed that the key to mental disorders such as depression lay in irrational beliefs. In his ABC model:

- A refers to an activating event

- B is the belief, which may be rational or irrational

- C is the consequence - rational beliefs lead to healthy emotions whereas irrational beliefs lead to unhealthy emotions.

Musturbatory Thinking - source of irrational beliefs - thinking that certain ideas or assumptions must be true in order for an individual to be happy. Ellis identified the three most important irrational beliefs. - I must be approved of or accepted by people i find important. - I must do well or very well, or i am worthless - The world must give me happiness, or i will die.

Aaron Beck also developed a cognitive explanation for mental disorder but one that focused specifically on depression. Beck believed that depressed individuals feel as they do because their thinking is biased towards negative interpretations of the world and they lack a perceived sense of control.

Negative Schema - acquired a negative schema during childhood - a tendency to adopt a negative view of the world. May be caused by a variety of factors, including parental and/or peer rejection and criticisms by teachers. These negative schemas are activated whenever the person encounters a new situation that resembles the original conditions in which these schemas were learned. Negative schemas lead to systematic cognitive biases in thinking.

The Negative Triad - A pessimistic and irrational view of three key elements in a person's belief system:

- The self; for example: 'I am just plain undesirable, what is there to like? I'm inattractive and seem to bore everyone.'

- The world; for example:'i can understand why people don't like me. They would all prefer someone else's company. Even my boyfriend left me'

- The future; for example: 'I am always going to be on my own, there is nothing that is going to change this,'

Evaluation:

- The view that depression is linked to irrational thinking is supported by research. Hammen and Krantz found that depressed participants made more errors in logic when asked to interpret written material than did non-depressed participants. Bates et al found that depressed participants who were given negative automatic-thought statements became more and more depressed. This research supports the view that negative thinking leads to depression, although this link does not mean that negative thoughts cause depression, Instead, negative thinking may develop because of their depression.

- The cognitive approach suggests that it is the client who is responsible for their disorder. This placing of emphasis on the client is a good thing because it gives the client the power to change the way things are. However this stance has limitations. It may lead the client or therapist to overlook situational factors, for example not considering how life events or family problems may have contributed to the mental disorder. The strength of the cognitive approach therefore lies in its focus on the client's mind and recovery, but other aspects of the client's environment and life may also need to be considered.

-One evaluation point for any theory is the consideration of whether it can be usefully applied. The cognitive explanations presented here have both been applied to CBT,as you can see on the next spread. CBT is consistently found to be the best treatment for depression, especially when used in conjunction with drug treatments. The usefulness of CBT as a therapy supports the effectiveness of the cognitive approach - if depression is alleviated by challenging irrational thinking, then this suggests such thoughts had a role in the depression in the first place.

Cognitive-Behaviour Therapy (CBT) - in the 1950s, Albert Ellis was one of the first psychologists to develop a form of CBT. He first called it 'rational therapy' to emphasise the fact that, as he saw it, psychological problems occur as a result of irrational thinking - individuals frequently develop self-defeating habits because of faulty beliefs about themselves and the world around them. The aim of therapy is to turn these irrational thoughts into rational ones.

Challenging irrational thoughts:

Ellis extended his ABC model to ABCDEF where:

- D refers to Disputing irrational thoughts and beliefs, E stands for the Effects of disputing and Effective attitude to life, F is the new Feelings that are produced.

The key issue to remember is that it is not the activating events that cause unproductive consequences - it is the beliefs that lead to the self-defeating consequences. REBT therefore focuses on challenging or disputing the irrational thoughts/beliefs and replacing them with effective, rational beliefs. For example:

-Logical disputing - self-defeating beliefs do not follow logically from the information availiable.

-Empirical disputing - self-defeating beliefs may not be consistent with reality.

-Pragmatic disputing - emphasises the lack of usefulness of self-defeating beliefs.

Effective disputing changes self-defeating beliefs into more rational beliefs. The client can move from catastrophising to more rational interpretations of events. Helps client feel better and eventually more self-accepting.

Homework - Clients are often asked to complete assignments between therapy sessions. This might include asking a person out on a date when they had been afraid to do so because of a fear of rejection. Such homework is vital in testing irrational beliefs against reality and putting new rational beliefs into practice.

Behavioural Activation - CBT often involves a specific focus on encouraging depressed clients to become more active and engage in pleasurable activities. Based on the common-sense idea that being active leads to rewards that act as an antidote to depression. A characteristic of many depressed people is that they no longer participate in activities that they previously enjoyed. In CBT, therapist and client identify potentially pleasurable activities and anticipate and deal with any cognitive obstacles.

Evaluation:

-Ellis claimed a 90% success rate for REBT, taking an average of 27 sessions to complete the treatment - impressive research support for his therapy. REBT, and CBT in general, have done well in outcome studies of depression. For example, a review by Cuijpers et al of 75 studies found that CBT was superior to no treatment. However, Ellis recognised that the therapy was not always effective, and suggested that this could be because some clients did not put their revised beliefs into action. Therapist competence also appears to explain a significant amount of the variation in CBT outcomes. This suggests that REBT is effective, but other factors relating to both client and therapist may limit its effectiveness.

-CBT appears to be more suitable for some individuals than others. For example, CBT appears to be less suitable for people who have high levels of irrational beliefs that are both rigid and resistant to change. CBT also appears to be less suitable in situations where high levels of stress in the individual reflect realistic stressors in the person's life that therapy cannot resolve. Ellis also explained a possible lack of success in terms of suitability - some people simply do not want the direct sort of advice that CBT practitioners tend to disperse; they prefer to share their worries with a therapist without getting involved in the cognitive effort associated with recovery. A limitation of CBT, therefore, is the fact that individual differences affect its effectiveness.

-The belief that changing behaviour can go some way to alleviating depression is supported by a study on the beneficial effects of exercise. Babyak et al studied 156 adult volunteers diagnosed with major depressive disorder. They were randomly assigned to a four-month course of aerobic exercise, drug treatment or a combination of the two. Clients in all three groups exhibited significant improvement at the end of the four months. Six months after the end of the study, those in the exercise group had significantly lower relapse rates than those in the medication group. This shows that a change in behaviour can indeed be beneficial in treating depression.

The COMT gene - may contribute to OCD. It is called the COMT gene because it is involved in the production of catechol-O-methyltransferase, or COMT for short. In turn, COMT regulates the production of the neurotransmitter dopamine that has been implicated in OCD. All genes come in different forms and one form of the COMT gene has been found to be more common in OCD patients than people without the disorder. This variation produces lower activity of the COMT gene and higher levels of dopamine.

The SERT gene - Another possible candidate is the SERT gene which affects the transport of the serotonin, creating lower levels of this neurotransmitter. These lower levels are also implicated in OCD. One study found a mutation of this gene in two unrelated families where six of the seven family members had OCD.

Diathesis-stress - The idea of a simple link between one gene and a complex disorder like OCD is unlikely. Something as simple as eye colour may have one gene that determines it but the same is not true for complex behaviours. Genes such as the SERT gene are also implicated in a number of other disorders such as depression and post-traumatic stress disorder. What this suggests is that each individual gene only creates a vulnerability for OCD as well as other conditions, such as depression. Other factors affect what condition develops or indeed whether any mental illness develops. Therefore some people could possess the COMT or SERT gene variations but suffer no ill effects.

As we have seen there is a link between genetic factors and abnormal levels of certain neurotransmitters, it is also true that genetic factors affect certain brain circuits that may be abnormal.

Abnormal levels of neurotransmitters - Dopamine levels are thought to be abnormally high in people with OCD. This is based on animal studies - high doses of drugs that enhance levels of dopamine induce stereotyped movements resembling the compulsive behaviours found in OCD patients. In contrast with dopamine, it is lower levels of serotonin that are associated with OCD. This conclusion is based on the fact that antidepressant drugs that increase serotonin activity have been shown to reduce OCD symptoms, whereas antidepressants that have less effect on serotonin do not reduce OCD symptoms.

Abnormal brain circuits - Several areas in the frontal lobes of the brain are thought to be abnormal in people with OCD. The caudate nucleus normally suppresses signals from the orbitofrontal cortex. In turn, the OFC sends signals to the thalamus about things that are worrying, such as a potential germ hazard. When the caudate nucleus is damaged, it fails to suppress minor 'worry' signals and the thalamus is alerted, which in turn sneds signals back to the OFC, acting as a worry circuit. This is supported by PET scans of patients with OCD, taken while their symptoms are active. Such scans show heightened activity in the OFC. Serotonin and dopamine are linked to these regions of the frontal lobes. Comer reports that serotonin plays a key role in the operation of the OFC and the caudate nuclei, and it would therefore appear that abnormal levels of serotonin might cause these areas to malfunction. 

Evaluation:

- Evidence for the genetic basis of OCD comes from studies of first-degree relatives and twin studies. Nestadt et al. identified 80 patients with OCD and 343 of their first-degree relatives and compared them with 73 control patients without mental illness and 300 of their relatives. They found that people with a first-degree relative with OCD had a five-times greater risk of having the illness themselves at some time in their lives, compared to the general population. A meta-analysis of 14 twin studies of OCD found that, on average, identical twins were more than twice as likely to develop OCD if their co-twin had the disorder than was the case for non-identical twins. This evidence points to a clear genetic basis for OCD, but the fact that the concordance rates are never 100% means that environmental factors must play a role too.

- Evidence of the role of genes in OCD comes from studies of people with other disorders. Pauls and Leckman studied patients with Tourette's syndrome and their families, and concluded that OCD is one form of expression of the same gene that determines Tourette's. The obsessional behaviour of OCD and Tourette's patients is also found in children with autism, who display stereotyped behaviours and rituals as well as compulsions. In addition, obsessive behaviour is typical of anorexia nervosa, and is one of the characteristics distinguishing individuals with anorexia from individuals with bulimia. Furthermore, it is reported that two out of every three patients with OCD also experience at least one episode of depression. This all supports the view that there is not one specific gene or genes unique to OCD, but they merely act as a predisposing factor towards obsessive-type behaviour.

-Many studies demonstrate the genetic link to abnormal levels of neurotransmitters. For example, Menzies et al used MRI to produce images of brain activity in OCD patients and their immediate family members without OCD and also a group of unrelated healthy people. OCD patients and their close relatives had reduced grey matter in key regions of the brain, including the OFC. This supports the view that anatomical differences are inherited and these may lead to OCD in certain individuals. Menzies et al. concluded that, in the future, brain scans may be used to detect OCD risk.

Antidepressants: SSRIs - most commonly used for OCD. Low levels of neurotransmitter serotonin are associated with depression as well as OCD, so drugs to increase levels of serotonin are used with both mental disorders. Low levels of serotonin are implicated in the 'worry circuit', so increasing levels of serotonin may therefore normalise this circuit. Antidepressants are used to reduce the anxiety associated with OCD. SSRIs, with brand names such as Zoloft, Paxil and Prozac, increase levels of serotonin, which regulates mood and anxiety.

Antidepressants: tricyclics - first antidepressant to be used for OCD and today is primarily used in the treatment of OCD rather than depression. Tricyclics block the transporter mechanism that re-absorbs both serotonin and noradrenaline into the pre-synaptic cell after it has fired. As a result, more of these neurotransmitters are left in the synapse, prolonging their activity, and easing transmission of the next impulse. Advantage of targeting more than one neurotransmitter. However, they have greater side effects so are used as a second-line treatment for patients where SSRIs are not effective.

Anti-anxiety drugs - Benzodiazepines are commonly used to reduce anxiety. They are manufactured under various trade names, such as Librium, Xanax, Valium and Diazepam. BZs slow down the activity of the neurotransmitter that, when released, has a general quitening effect on many of the neurons in the brain. It does this by reacting with special sites on the outside of receiving neurons. When GABA locks on to these receptors it opens a channel that increases the flow of chloride ions into the neuron.

Evaluation:

-There is considerable evidence for the effectiveness of drug treatments. Typically a randomised control trial is used to compare the effectiveness of the drug versus a placebo. Soomro et al. reviewed 17 studies of the use of SSRIs with OCD patients and found them to be more effective than placebos in reducing the symptoms of OCD up to three months after treatment. One of the issues regarding the evaluation of treatment is that most studies are only of three to four months' duration. Therefore, while drug treatments have been shown to be effective in the short term, the lack of long-term data is a limitation.

- One of the great appeals of using drug therapy is that it requires little input from the user in terms of time and effort. In contrast, therapies such as CBT require the patient to attend regular meetings and put considerable thought into tackling their problems. Drug therapies are also cheaper for the health service because they require little monitoring and cost much less than psychological treatments. Furthermore, patients may benefit simply from talking to the doctor during consultations. These benefits means that drug therapies are more economical for the health service than psychological therapies.

- All drugs have side effects, some more severe than others. For example, nausea, headache and insomnia are common side effects of SSRIs. Although not necessarily severe, they are often enough to make a patient stop taking the drug. Tricyclic antidepressants tend to have more side effects than SSRIs and so are only used in cases where SSRIs are not effective. The possible side effects of BZs include increased aggressiveness and long-term impairment of memory. There are also problems with addiction, so the recommendation is that BZ use should be limited to a maximum of four weeks. These side effects, and the possibility of addiction, therefore limit the usefulness of drugs as treatments for OCD.

Evaluation:

-There is considerable evidence for the effectiveness of drug treatments. Typically a randomised control trial is used to compare the effectiveness of the drug versus a placebo. Soomro et al. reviewed 17 studies of the use of SSRIs with OCD patients and found them to be more effective than placebos in reducing the symptoms of OCD up to three months after treatment. One of the issues regarding the evaluation of treatment is that most studies are only of three to four months' duration. Therefore, while drug treatments have been shown to be effective in the short term, the lack of long-term data is a limitation.

- One of the great appeals of using drug therapy is that it requires little input from the user in terms of time and effort. In contrast, therapies such as CBT require the patient to attend regular meetings and put considerable thought into tackling their problems. Drug therapies are also cheaper for the health service because they require little monitoring and cost much less than psychological treatments. Furthermore, patients may benefit simply from talking to the doctor during consultations. These benefits means that drug therapies are more economical for the health service than psychological therapies.

- All drugs have side effects, some more severe than others. For example, nausea, headache and insomnia are common side effects of SSRIs. Although not necessarily severe, they are often enough to make a patient stop taking the drug. Tricyclic antidepressants tend to have more side effects than SSRIs and so are only used in cases where SSRIs are not effective. The possible side effects of BZs include increased aggressiveness and long-term impairment of memory. There are also problems with addiction, so the recommendation is that BZ use should be limited to a maximum of four weeks. These side effects, and the possibility of addiction, therefore limit the usefulness of drugs as treatments for OCD.