Schizophrenia Revisions Notes

What do the examiners look for?

  • Accurate and detailed knowledge
  • Clear, coherent and focused answers
  • Effective use of terminology (use the “technical terms”)

In application questions, examiners look for “effective application to the scenario” which means that you need to describe the theory and explain the scenario using the theory making the links between the two very clear. If there is more than one individual in the scenario you must mention all of the characters to get to the top band.

Difference between AS and A level answers

The descriptions follow the same criteria; however you have to use the issues and debates effectively in your answers. “Effectively” means that it needs to be clearly linked and explained in the context of the answer.

Read the model answers to get a clearer idea of what is needed.

Schizophrenia is a severe mental illness where contact with reality and insight are impaired, an example of psychosis.

Section 1: Diagnosis and Classification of Schizophrenia

Classification is the process of organising symptoms into categories based on which symptoms cluster together in sufferers. Psychologists use the DSM and ICD to diagnose a patient with schizophrenia.

Diagnosis refers to the assigning of a label of a disorder to a patient. The ICD-10 (only negative symptoms need to be present) is used worldwide and the DSM-5 (only positive symptoms need to be present) is used in America.

In order to diagnose Schizophrenia the Mental Health Profession developed the DSM (Diagnostic and Statistical Manual) still used today as a method of classifying mental disorders (particularly in the USA).

It is also used as a basis for the ICD (International Classification of Diseases) used by the World Health Organisation in classifying all disorders (mental and physical).

Note: you may come across the terms DSM-IV and ICD-10. These refer to the latest editions of the two classification systems.

Positive Symptoms

an excess or distortion of normal functions: including hallucinations and

Positive symptoms are an excess or distortion of normal functions, for example hallucinations, delusions and thought disturbances such as thought insertion.


• Hallucinations are usually auditory or visual perceptions of things that are not present. Imagined stimuli could involve any of the senses. Voices are usually heard coming from outside the person’s head giving instructions on how to behave.

• Delusions are false beliefs. Usually the person has convinced him/herself that he/she is someone powerful or important, such as Jesus Christ, the Queen (e.g. Delusions of Grandeur). There are also delusions of being paranoid, worrying that people are out to get them.

• Psychomotor Disturbances: Stereotypyical – Rocking backwards and forwards, twitches, & repetitive behaviors.
Catatonia- staying in position for hours/days on end, cut off from the world.

Negative Symptoms

where normal functions are limited: including speech poverty and avolition.

Negative symptoms are a diminution or loss of normal functions such as psychomotor disturbances, avolition (the reduction of goal-directed behavior), disturbances of mood and thought disorders.


• Thought disorder in which there are breaks in the train of thought and the person appears to make illogical jumps from one topic to another (loose association). Words may become confused and sentences incoherent (so called ‘word salad). Broadcasting is a thought disorder whereby a person believes their thoughts are being broadcast to others, for example over the radio or through TV. Alogia – aka speech poverty – is a thought disorder were correct words are used but with little meaning.

• Avolition: Lack of volition (i.e. desire): in which a person becomes totally apathetic and sits around waiting for things to happen. They engage in no self motivated behavior. Their get up and go has got up and gone!

Reliability and Validity in Diagnosis and Classification of Schizophrenia

with reference to co-morbidity,
culture and gender bias and symptom overlap.



For the classification system to be reliable, differfent clinicians using the same system (e.g. DSM) should arrive at the same diagnosis for the same individual.

Reliability is the level of agreement on the diagnosis by different psychiatrists across time and cultures; stability of diagnosis over time given no change in symptoms.



Validity – the extent to which schizophrenia is a unique syndrome with characteristics, signs and symptoms.

For the classification system to be valid it should be meaningful and classify a real pattern of symptoms, which result from a real underlying cause.

Section 2: Biological Explanations for Schizophrenia


Family studies find individuals who have schizophrenia and determine whether their biological relatives are similarly affected more often than non-biological relatives.

There are two types of twins – identical (monozygotic) and fraternal (dizygotic). To form identical twins, one fertilised egg (ovum) splits and develops two babies with exactly the same genetic information.


• Gottesman (1991) found that MZ twins have a 48% risk of getting schizophrenia whereas DZ twins have a 17% risk rate. This is evidence that the higher the degree of genetic relativeness, the higher the risk of getting schizophrenia.

• Benzel et al. (2007) three genes: COMT, DRD4, AKT1 – have all been associated with excess dopamine in specific D2 receptors, leading to acute episodes, positive symptoms which include delusions, hallucinations, strange attitudes.

• Research by Miyakawa et al. (2003) studied DNA from human families affected by schizophrenia and found that those with the disease were more likely to have a defective version of a gene, called PPP3CC which is associated with the production of calcineurin which regulates the immune system. Also, research by Sherrington et al. (1988) has found a gene located on chromosome 5 which has been linked in a small number of extended families where they have the disorder.

• Evidence suggests that the closer the biological relationship, the greater the risk of developing schizophrenia. Kendler (1985) has shown that first-degree relatives of those with schizophrenia are 18 times more at risk than the general population. Gottesman (1991) has found that schizophrenia is more common in the biological relatives of a schizophrenic, and that the closer the degree of genetic relatedness, the greater the risk.

The Dopamine Hypothesis


• Dopamine is a neurotransmitter. It is one of the chemicals in the brain which causes neurons to fire. The original dopamine hypothesis stated that schizophrenia suffered from an excessive amount of dopamine. This causes the neurons that use dopamine to fire too often and transmit too many messages.

• High dopamine activity leads to acute episodes, and positive symptoms which include: delusions, hallucinations, confused thinking.

• Evidence for this comes from that fact that amphetamines increase the amounts of dopamine . Large doses of amphetamine given to people with no history of psychological disorders produce behavior which is very similar to paranoid schizophrenia. Small doses given to people already suffering from schizophrenia tend to worsen their symptoms.

• A second explanation developed, which suggests that it is not excessive dopamine but that fact that there are more dopamine receptors. More receptors lead to more firing and an over production of messages. Autopsies have found that there are generally a large number of dopamine receptors (Owen et al., 1987) and there was an increase in the amount of dopamine in the left amygdale (falkai et al. 1988) and increased dopamine in the caudate nucleus and putamen (Owen et al, 1978).

Neural Correlates


• Neural correlates are patterns of structure or activity in the brain that occur in conjunction with schizophrenia

• People with schizophrenia have abnormally large ventricles in the brain . Ventricles are fluid filled cavities (i.e. holes) in the brain that supply nutrients and remove waste. This means that the brains of schizophrenics are lighter than normal. The ventricles of a person with schizophrenia are on average about 15% bigger than normal (Torrey, 2002).

Section 3: Psychological Explanations for Schizophrenia

Family Dysfunction

Family Dysfunction refers to any forms of abnormal processes within a family such as conflict, communication problems, cold parenting, criticism, control and high levels of expressed emotions.

These may be risk factors for the development and maintenance of schizophrenia.


• Laing and others rejected the medical / biological explanation of mental disorders. They did not believe that schizophrenia was a disease. They believed that schizophrenia was a result of social pressures from life. Laing believed that schizophrenia was a result of the interactions between people, especially in families.

• Bateson et al. (1956) suggested the double bind theory, which suggests that children who frequently receive contradictory messages from their parents are more likely to develop schizophrenia. For example parents who say they care whilst appearing critical or who express love whilst appearing angry. They did not believe that schizophrenia was a disease. They believed that schizophrenia was a result of social pressures from life.

• Prolonged exposure to such interactions prevents the development of an internally coherent construction of reality; in the long run, this manifests itself as typically schizophrenic symptoms such as flattening affect, delusions and hallucinations, incoherent thinking and speaking, and in some cases paranoia.

• Another family variable associated with schizophrenia is a negative emotional climate, or more generally a high degree of expressed emotion (EE). EE is a family communication style that involves criticism, hostility and emotional over-involvement. The researchers concluded that this is more important in maintaining schizophrenia than in causing it in the first place, (Brown et al 1958). Schizophrenics returning to such a family were more likely to relapse into the disorder than those returning to a family low in EE. The rate of relapse was particularly high if returning to a high EE family was coupled with no medication.

Cognitive explanations

including dysfunctional thought processing.

Cognitive approaches examine how people think, how they process information. Researchers have focused on two factors which appear to be related to some of the experiences and behaviors of people diagnosed with schizophrenia.

First, cognitive deficits which are impairments in thought processes such as perception, memory and attention. Second, cognitive biases are present when people notice, pay attention to, or remember certain types of information better than other.


Cognitive Deficits

• There is evidence that people diagnosed as schizophrenic have difficulties in processing various types of information, for example visual and auditory information. Research indicates their attention skills may be deficient – they often appear easily distracted.

• A number of researchers have suggested that difficulties in understanding other people’s behavior might explain some of the experiences of those diagnosed as schizophrenic. Social behavior depends, in part, on using other people’s actions as clues for understanding what they might be thinking. Some people who have been diagnosed as schizophrenic appear to have difficulties with this skill.

• Cognitive deficits have been suggested as possible explanations for a range of behaviors associated with schizophrenia. These include reduced levels of emotional expression, disorganised speech and delusions.

Cognitive Biases

Cognitive biases refer to selective attention. The idea of cognitive biases has been used to explain some of the behaviors which have been traditionally regarded as ‘symptoms’ of ‘schizophrenia’.

• Delusions: The most common delusion that people diagnosed with schizophrenia report is that others are trying to harm or kill them – delusions of persecution. Research suggests that these delusions are associated with specific biases in reasoning about and explaining social situations. Many people who experience feelings of persecution have a general tendency to assume that other people cause the things that go wrong with their lives.

Section 4: Drug Therapy: typical and atypical antipsychotics

Drug therapy is a biological treatment for schizophrenia. Antipsychotic drugs are used to reduce the intensity of symptoms (particularly positive symptoms).

Typical Antipsychotics


• First generation Antipsychotics are called “Typical Antipsychotics”
Eg. Chlorpromazine and Haloperidol.

• Typical antipsychotic drugs are used to reduce the intensity of positive symptoms, blocking dopamine receptors in the synapses of the brain and thus reducing the action of dopamine.

• They arrest dopamine production by blocking the D2 receptors in synapses that absorb dopamine, in the mesolimbic pathway thus reducing positive symptoms, such as auditory hallucinations.

• But they tended to block ALL types of dopamine activity, (in other parts of the brain as well) and this caused side effects and may have been harmful.

Atypical Antipsychotics

• Newer drugs, called “atypical antipsychotics” attempt to target D2 dopamine activity in the limbic system but not D3 receptors in other parts of the brain.

• Atypical antipsychotics such as Clozapine bind to dopamine, serotonin and glutamate receptors.

• Atypical antipsychotic drugs work on negative symptoms, improving mood, cognitive functions and reducing depression and anxiety.

• They also have some effect on other neurotransmitters such as serotonin .
They generally have fewer side effects eg. less effect on movement
Eg. Clozapine, Olazapine and Risperidone.

Exam Tip

In most cases the original “typical antipsychotics” have more side effects, so if the exam paper asks for two biological therapies you can write about typical anti-psychotics and emphasise the side effects, then you can write about the atypical antipsychotics and give them credit for having less side effects.

Section 5: Psychological Therapies for Schizophrenia

Family Therapy

Family therapy is a form of therapy carried out with members of the family with the aim of improving their communication and reducing the stress of living as a family.

Family Therapy aims to reduce levels of expressed emotion, and reduced the likelihood of relapse.

Aims of Family Therapy

• To educate relatives about schizophrenia.

• To stabilize the social authority of the doctor and the family.

• To improve how the family communicated and handled the situation.

• To teach patients and carers more effective stress management techniques.

Methods used in Family Therapy

• Pharoah identified examples of how family therapy works: It helps family members achieve a balance between caring for the individual and maintaining their own lives, it reduces anger and guilt, it improves their ability to anticipate and solve problems and forms a therapeutic alliance.

• Families taught to have weekly family meetings solving problems on family and individual goals, resolve conflict between members, and pinpoint stressors.

• Preliminary analysis: Through interviews and observation the therapist identifies strengths and weaknesses of family members and identifies problem behaviors.

• Information transfer – teaching the patient and the family the actual facts about the illness, it’s causes, the influence of drug abuse, and the effect of stress and guilt.

• Communication skills training – teach family to listen, to express emotions and to discuss things. Additional communication skills are taught, such as “compromise and negotiation,” and “requesting a time out” . This is mainly aimed at lowering expressed emotion.

Token Economy


• Token economies aim to manage schizophrenia rather than treat it.

• They are a form of behavioral therapy where desirable behaviors are encouraged by the use of selective reinforcement and is based on operant conditioning.

• When desired behavior is displayed eg. Getting dressed, tokens (in the form of coloured discs) are given immediately as secondary reinforcers which can be exchanged for rewards eg. Sweets and cigarettes. • This manages schizophrenia because it maintains desirable behavior and no longer reinforces undesirable behavior.

• The focus of a token economy is on shaping and positively reinforcing desired behaviors and NOT on punishing undesirable behaviors. The technique alleviates negative symptoms such as poor motivation, and nurses subsequently view patients more positively, which raises staff morale and has beneficial outcomes for patients.

• It can also reduce positive symptoms by not rewarding them, but rewarding desirable behavior instead.
Desirable behavior includes self-care, taking medication, work skills, and treatment participation.

Cognitive Behavioral Therapy


In CBT, patients may be taught to recognise examples of dysfunctional or delusional thinking, then may receive help on how to avoid acting on these thoughts. This will not get rid of the symptoms of schizophrenia but it can make patients better able to cope with them.

Central idea: Patients problems are based on incorrect beliefs and expectations. CBT aims to identify and alter irrational thinking including regarding:

  • General beliefs.
  • Self image.
  • Beliefs about what others think.
  • Expectations of how others will act.
  • Methods of coping with problems.

In theory, when the misunderstandings have been swept away, emotional attitudes will also improve.

Assessment: The therapist encourages the patient to explain their concerns.

• describing delusions

• reflecting on relationships

• laying out what they hope to achieve through the therapy.


The therapist wins the trust of the patient, so they can work together.
This requires honesty, patience and unconditional acceptance. The therapist needs to accept that the illusions may seem real to the patient at the time and should be dealt with accordingly.

ABC: Get the patients to understand what is really happening in their life:

A: Antecedent – what is triggering your problem ?

B: behavior – how do you react in these situations ?

C: Consequences – what impact does that have on your relationships with others?


Help the patient realise it is normal to have negative thoughts in certain situations. Therefore there is no need to feel stressed or ashamed about them.

Critical Collaborative Analysis:

Carrying on a logical discussion till the patient begins to see where their ideas are going wrong and why they developed. Work out ways to recognise negative thoughts and test faulty beliefs when they arise, and then challenge and re-think them.

Developing Alternative Explanations:

Helping the patient to find logical reasons for the things which trouble them
Let the patient develop their own alternatives to their previous maladaptive behavior by looking at coping strategies and alternative explanations.

Another form of CBT: Coping Strategy Enhancement (CSE)

• Tarrier (1987) used detailed interview techniques, and found that people with schizophrenia can often identify triggers to the onset of their psychotic symptoms, and then develop their own methods of coping with the distress caused. These might include things as simple as turning up the TV to drown out the voices they were hearing!

• At least 73% of his sample reported that these strategies were successful in managing their symptoms.

• CSE aims to teach individuals to develop and apply effective coping strategies which will reduce the frequency, intensity and duration of psychotic symptoms and alleviate the accompanying distress. There are two components:

1. Education and rapport training: therapist and client work together to improve the effectiveness of the client’s own coping strategies and develop new ones.

2. Symptom targeting: a specific symptom is selected for which a particular coping strategy can be devised
Strategies are practised within a session and the client is helped through any problems in applying it. They are then given homework tasks to practice, and keep a record of how it worked.

Section 6: Interactionist Approach

The Interactionist approach acknowledges that there are a range of factors (including biological and psychological) which are involved in the development of schizophrenia.

The Diathesis-stress Model


• The diathesis-stress model states that both a vulnerability to SZ and a stress trigger are necessary to develop the condition.

• Zubin and Spring suggest that a person may be born with a predisposition towards schizophrenia which is then triggered by stress in everyday life. But if they have a supportive environment and/or good coping skills the illness may not develop.

• Concordance rates are never 100% which suggests that environmental factors must also play a role in the development of SZ. MZ twins may have the same genetic vulnerability but can be triggered by different stressors.

• Tienari Et. A. (2004): Adopted children from families with schizophrenia had more chance of developing the illness than children from normal families. This supports a genetic link.

However, those children from families schizophrenia were less likely to develop the illness if placed in a “good” family with kind relationships, empathy, security, etc. So environment does play a part in triggering the illness.

Saul Mcleod, PhD

BSc (Hons) Psychology, MRes, PhD, University of Manchester

Educator, Researcher

Saul Mcleod, Ph.D., is a qualified psychology teacher with over 18 years experience of working in further and higher education.

Bruce Johnson

A-level Psychology Teacher

B.A., History and Educational Psychology, University of Exeter

Bruce Johnson is an A-level psychology teacher, and head of the sixth form at Caterham High School.