Mental illness can be difficult for people to understand, because they cannot see any physical effects. People make unkind comments such as 'Pull yourself together – it's all in your head.' The effect of a heart attack cannot be seen just by looking at someone who has had one, but it can be seen by carrying out some simple tests that will enable you to see a blockage to the arteries that supply the heart with blood, and see that the heart muscle has died as a result.

It's also difficult for people who are providing mental health care¹. They can't see what's going on, neither can they perform any tests to see what is wrong with the brain on a microscopic level. To find out what is going wrong and how to get it right again, they can only see the effects it is having on someone's life, feelings and actions.

What Is a Model and Why Use One Anyway?

As it is impossible to understand every factor that may have an impact on a mental illness and how they interact in each particular case, we have to treat patients based on the best we know at the moment. To do this a model is formed - a group of linked theories that are used to explain the cause and to predict the most appropriate treatment.

'The Nature of Swans' - an Example of a Model

If that seemed complicated, think of this example. Suppose you wanted to work out what the definition of a swan was, and the only way to do this was to go out and look at swans. You see that every swan is swan-shaped and white, therefore for something to be a swan it must be swan-shaped and white. You could publish this theory in a book, and people could use the book to identify swans. This works well until, sooner or later, someone spots a black swan. Then they create a new model, saying 'All swans are swan-shaped and coloured black or white'. The new model takes the place of the previous model; however, we cannot be sure that it is the truth until we see every swan in the world. Somewhere there may be a purple swan, and the model of 'What is a swan?' will be rewritten again. The fact that it may be disproved in the future doesn't make the model invalid; we can still use it at the moment to spot swans, as long as we keep it in mind that there may be swans of other colours around.

The three main models of mental illness can be applied to most illnesses. To explain them, let's look at an example of a case and see how different models would explain it.

A Example Case - Anna

Anna is a (fictional) 33 year old woman who has been suffering from low mood for the last two months. She's also been feeling tired all of the time. She doesn't find any of her hobbies enjoyable any more and finds it difficult to enjoy anything. She's also been waking up earlier than she used to, and her appetite has decreased.

Each model would have a different interpretation of the causes of Anna's depression. As a result, each would suggest a different treatment.

Biological Models

Biological models of mental illness see mental illness as being no different from any physical illness; it has physical causes and therefore requires physical treatments.

Biological models include theories which state that mental illnesses are caused by chemicals. Often the chemical proposed as a cause of mental illness is a neurotransmitter². Other biological models suggest that illnesses are caused by genetic factors or by hormonal imbalances.

Biological interventions are usually treatments with drugs which seek to reverse the chemical imbalance. For instance, some drugs which are used for depression, such as Prozac, increase the availability of a chemical called 5HT3, or serotonin in the US.

A biological model of Anna's problem might say that her low mood is caused by decreased levels of chemicals known as monoamines. A treatment may therefore be to prescribe a drug to increase monoamine levels.

Psychological Models

Psychological models say that the real cause of mental illnesses can be found if a psychologist studies the psychology of the patient. There is a variety of psychological therapies which tend to all be grouped together as 'counselling'. Some of the more common ones include psychoanalysis and cognitive behavioural therapy.

Psychoanalysis is the form of therapy most highly based on the teachings of Freud, and may involve many years of sessions. The therapist remains passive and helps the patient work through the unconscious basis of their problems instead of providing solutions. They will also talk about the past, as that may have an impact on current problems. The therapist ought to be closely supervised, usually with a support group themselves. A psychoanalyst would spend time listening to Anna while she talked about her problems and would examine where they originated from.

Where psychoanalysis may concentrate on events from the past that may not be changed, other psychological therapies, such as cognitive, behavioural, or cognitive behavioural therapy³, would concentrate on changing factors that could be changed, such as reducing negative thoughts and guilt.

Some people who believe in psychological models would say that, as the real cause of the problem is psychological, the use of medication to make a patient feel better is not treating the problem. According to the psychological model, after a patient has taken medications the cause of the problem is still there, therefore the patient is not treated.

Social Models

There are two main types of social model of mental illness.

The 'Theory of Labelling' states that behaviours disliked by society are labelled as symptoms of a psychiatric illness. This leads to the person thinking that they have a mental illness. It also leads to them losing status in society, for example by losing their job. People who use this theory would think that the use of medication is unnecessary, as the problem is society's definition of 'normal behaviour'.

Another theory is that social situations can lead to a mental illness. For instance poverty leads to situations that a person cannot control, which can lead the person to develop anxiety. It is difficult to test this theory, because most researchers use classification systems that depend on the job a person does, or (if they are not working) the job of the main earner in their family, or the last job that they did. If a person was in a well paid job and became mentally ill they would have to give up the job, and so would no longer be in the same social class. Again this theory would think that medication was not causing the problem, as the cause of the problem was the situation that the patient was placed in.

A social explanation of Anna's problems would say that she may have been labelled neurotic as a result of the stress that was placed on her by society. Social models are rarely used to treat patients though they are used in prevention of mental illness.

In Reality

Doctors helping people with mental illness have models to guide them in both diagnosis and treatment. Most models of mental illnesses will nowadays acknowledge a combination of biological, psychological and social factors. Different models will, however, vary in which factors they rate as the most important. When advising a patient, a doctor tries to look at which intervention(s) are likely to work best for that particular patient, taking into account the patient's symptoms and circumstances.

Models are the basis of every scientific belief. As our understanding of the human mind is less complete than our understanding of the human heart our models of diseases of the human mind are less complete than our models of disease of the human heart. Some people with mental illness find that medications have turned their life around, others find that psychological treatments were the key to solving their problems.