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The Medical Model

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The medical model of abnormal psychology treats mental disorders in the same way as a broken arm, i.e. there is thought to be a physical cause.

Supporters of the medical model consequently consider symptoms to be outward signs of the inner physical disorder and believe that if symptoms are grouped together and classified into a ‘syndrome’ the true cause can eventually be discovered and appropriate physical treatment administered.

Assumptions

  • The biological approach to psychopathology believes that disorders have an organic or physical cause. The focus of this approach is on genetics, neurotransmitters, neurophysiology, neuroanatomy etc. The approach argues that mental disorders are related to the physical structure and functioning of the brain.

  • Behaviors such as hallucinations are 'symptoms' of mental illness as are suicidal ideas or extreme fears such as phobias about snakes and so on.  Different illnesses can be identified as 'syndromes', clusters of symptoms that go together and are caused by the illness.

  • These symptoms lead the psychiatrist to make a 'diagnosis' for example 'this patient is suffering from a severe psychosis, he is suffering from the medical condition we call schizophrenia'.

What is happening here? The doctor makes a judgement of the patient's behavior, usually in a clinical interview after a relative or general practitioner has asked for an assessment.  The doctor will judge that the 'patient' is exhibiting abnormal behavior by asking questions and observing the patient.

Judgement will also be influenced heavily by what the relatives and others near to the patient say and the context – is mental illness more likely to be diagnosed in a mental hospital.

Treatment – On the basis of the diagnosis, the doctor will prescribe treatment such as drugs, psychosurgery or electroconvulsive therapy.

Schizophrenia

The main biological explanations of schizophrenia are as follows:

  • Genetics – there is considerable evidence of a genetic predisposition to develop schizophrenia.

  • Biochemistry – the dopamine hypothesis argues that elevated levels of dopamine are related to symptoms of schizophrenia.

  • Neuroanatomy – differences in brain structure (abnormalities in the frontal and pre-frontal cortex, enlarged ventricles) have been identified in people with schizophrenia.

Depression

The main biological explanations of depression are as follows:

  • Genetic – there is considerable evidence that the predisposition to develop depression is inherited.

  • Biochemistry, e.g Amine hypothesis – low levels of mono amines predominantly noradrenaline and serotonin.

  • Neuroanatomy – damage to amine pathways in post-stroke patients.

  • Neuroendocrine (hormonal) factors – the importance of stress hormones (eg cortisol) and over activity of the HPA axis which is responsible for the stress response.

OCD

The main biological explanations of OCD are as follows:

  • Genetic – there is some evidence of a tendency to inherit OCD, with a gene (Sapap3) recently identified.

  • Biochemistry – serotonin deficiency has been implicated.

  • Neuroanatomy – dysfunctions of the orbital frontal cortex ( OFC ) over-activity in basal ganglia and caudate-nucleus thalamus have been proposed .

  • Evolutionary – adaptive advantages of hoarding, grooming, etc.

Drug Treatment

drugs

The film One flew over the cuckoos nest demonstrates the way in which drugs are handed out like smarties merely to keep the patients subdued.

Note also in the film that the same type of drug is given to every patient with no regard for the individual’s case history or symptoms; the aim is merely to drug them up to the eye balls to shut them up!

The main drugs used in the treatment of depression, anxiety and OCD are mono-amine oxidase inhibitors (MAOIs), tricyclic antidepressants and selective serotonin reuptake inhibitors (SSRIs).

Antipsychotic drugs can be used to treat schizophrenia by blocking d2 (dopamine) receptors. There are different generations of antipsychotics:

  1. Typical antipsychotics – eg chlorpromazine, block d2 receptors in several brain areas.

  2. Less typical antipsychotics – eg pimozide, often used as a last resort when other drugs have failed.

  3. Atypical antipsychotics – eg risperidone. Some atypicals also block serotonin receptors.

Effectiveness

  • Anti psychotics have long been established as a relatively cheap, effective treatment, which rapidly reduce symptoms and enable many people to live relatively normal lives (Van Putten, 1981).

  • Relapse is likely when drugs are discontinued.

  • Drug treatment is usually superior to no treatment.

  • Between 50 – 65% of patients benefit from drug treatments.

Appropriateness

  • Drugs do not deal with the cause of the problem, they only reduce the symptoms.

  • Anti psychotics produce a range of side effects including motor tremors and weight gain. These lead a proportion of patients to discontinue treatment.

  • Patients often welcome drug therapy, as it is quicker, easier and less threatening than talk therapy.

  • Some drugs cause dependency.

  • Ethical issues including informed consent, and the dehumanizing effects of some treatments.

drug treatments table

Electro Convulsive Therapy (ECT)

Electro Convulsive Therapy (ECT) began in the 1930’s after it was noticed that when cows are executed by electric shocks they appear to convulse as if they are having an epileptic shock.

The idea was extrapolated to humans as a treatment for schizophrenia on the theoretical basis that nobody can have schizophrenia and epilepsy together, so if epilepsy is induced by electric shock the schizophrenic symptoms will be forced into submission!

ECT was used historically but was largely abandoned as a treatment for schizophrenia after the discovery of the antipsychotic drugs in the 1950s but has recently been re-introduced in the USA. In the UK, the use of ECT is not recommended by NICE except in very particular cases (mainly for catatonic schizophrenia). However, it is sometimes used as a last resort for treating severe depression.

ECT can be either unilateral (electrode on one temple) or bilateral (electrodes on both temples).

The procedure for administering ECT involves the patient receiving a short acting anaesthetic and muscle relaxant before the shock is administered. Oxygen is also administered. Small amount of current (about 0.6 amps) passed through the brain lasting for about half a second. The resulting seizure lasts for about a minute. ECT is usually given three times a week for up to 5 weeks.

There are many critics of this extreme form of treatment, especially of its uncontrolled and unwarranted use in many large, under staffed mental institutions where it may be used simply to make patients docile and manageable or as a punishment (Breggin 1979).

ECT side effects include impaired language and memory as well as loss of self esteem due to not being able to remember important personal facts or perform routine tasks.

There is a debate on the ethics of using ECT, primarily because it often takes place without the consent of the individual and we don’t know how it works!

There are three theories as to how ECT may work:

  1. The shock literally shocks the person out of their illness as it is regarded as a punishment for the inappropriate behavior.

  2. Biochemical changes take place in the brain following the shocks which stimulate particular neurotransmitters.

  3. The associated memory loss following shock allows the person to start afresh. They literally forget they were depressed or suffering from schizophrenia.

Psychosurgery

psychosurgery

As a last result when drugs and ECT have apparently failed psychosurgery is an option. This basically involves either cutting out brain nerve fibres or burning parts of the nerves that are thought to be involved in the disorder (when the patient is conscious).

The most common form of psychosurgery is a prefrontal lobotomy.

Unfortunately these operations have a nasty tendency to leave the patient vegetablized or ‘numb’ with a flat personality, shuffling movements etc. due to their inaccuracy. Moniz ‘discovered’ the lobotomy in 1935 after successfully snatching out bits of chimps’ brains.

It didn’t take long for him to get the message that his revolutionary treatment was not so perfect; in 1944 a rather dissatisfied patient called his name in the street and shot him in the spine, paralysing him for life! As a consolation he received the Nobel prize for his contribution to science in 1949.

Surgery is used only as a last resort, where the patient has failed to respond to other forms of treatment and their disorder is very severe. This is because all surgery is risky and the effects of neurosurgery can be unpredictable. Also, there may be no benefit to the patient and the effects are irreversible.

Psychosurgery has scarcely been used as a treatment for schizophrenia since the early 1970’s when it was replaced by drug treatment.

There are four major types of lobotomy:

lobotomy medical model

BBC Radio 4: The Lobotomists. This programme tells the story of three key figures in the strange history of lobotomy - and for the first time explores the popularity of lobotomy in the UK in detail.

Evaluation of The Medical Model

Strengths:

    • It is objective, being based on mature biological science.

    • It has given insight into the causes of some conditions, such as GPI and Alzheimer's disease, an organic condition causing confusion in the elderly.

    • Treatment is quick and, relative to alternatives, cheap and easy to administer. It has proved to be effective in controlling serious mental illness like schizophrenia allowing patients who would otherwise have to remain in hospital to live at home.

    • The sickness label has reduced the fear of those with mental disorders. Historically, they were thought to be possessed by evil spirits or the devil – especially women who were burned as witches!

Weaknesses:

    • The treatments have serious side-effects, for example ECT can cause memory loss, and they are not always effective. Drugs may not 'cure' the condition, but simply act as a chemical straitjacket.

    • The failure to find convincing physical causes for most mental illnesses must throw the validity of the medical model into question, for example affective disorders and neuroses. For this reason, many mental disorders are called 'functional'. The test case is schizophrenia but even here genetic or neurochemical explanations are inconclusive. The medical model is therefore focused on physical causes and largely ignores environmental or psychological causes.

    • There are also ethical problems in labelling someone mentally ill – Szasz says that, apart from identified diseases of the brain, most so-called mental disorders are really problems of living. Labelling can lead to discrimination and loss of rights.

    • The medical model has been the one that has been most influential in determining the way that mentally disturbed people are treated, but most psychologists would say that at best, it only provides a partial explanation, and may even be totally inappropriate.

References

Breggin, P. R. (1979). Electroshock, Its Brain-disabling Effects. New York: Springer Publishing Company.

Moniz, E. (1935). Angiomes cérébraux. Importance de l’angiographie cérébrale dans leur diagnostic. Bull. Acad. Méd.(Paris), 3, 113.

Van Putten, T., May, P. R., Marder, S. R., & Wittmann, L. A. (1981). Subjective response to antipsychotic drugs. Archives of General Psychiatry, 38(2), 187-190.

How to cite this article:

McLeod, S. A. (2008). The Medical Model. Retrieved from http://www.simplypsychology.org/medical-model.html

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