aqa  A2 Option: Classification of schizophrenia. Positive symptoms of schizophrenia, including hallucinations and delusions. Negative symptoms of schizophrenia, including speech poverty and avolition. 

edexcel  Description of symptoms and features, including thought insertion, hallucinations, delusions, disordered thinking.



Schizophrenia is a chronic mental health condition that causes a range of different psychological symptoms. Common symptoms include:

  • hallucinations – hearing and seeing things that do not exist
  • delusions – believing things that are not true and so schizophrenia is therefore a psychosis, not a neurosis, as the patient does not realise they have a condition.

The exact cause of schizophrenia is unknown as of yet, although there are a number of possible explanations. Two are covered in this unit. The NHS suggests that as many as 1 of every 100 people will suffer at least one episode of acute schizophrenia in their lifetime, although Jablensky (2000) suggested that the disorder is found in about 1.4 to 4.6 people in every one thousand for any nation, on average.

Men and women appear equally affected by schizophrenia, although in men it is typically active between the ages of 15 and 30, whereas in women it usually becomes active between 20 and 30. It is commonly thought that schizophrenics have a split personality, acting perfectly normal one minute, and then irrationally the next. However, this is not the case, and though ‘schizophrenia’ derives from Greek and German words meaning ‘split mind’, it is not a split personality disorder. Sufferers are said to suffer episodes of dysfunction, however.

Most studies confirm that there is some link between schizophrenia and violence, although the media tends to exaggerate this. In reality, a sufferer is actually more likely to be the victim of violence than the initiator of a violent attack. Experts at the RCP estimate that less than 1% of UK violent crime is committed by schizophrenics.

When discussing mental disorders, symptoms are what characterise the disorder, describing ways in which sufferers think, feel and behave. Symptoms of schizophrenia are broken down into positive symptoms and negative symptoms. Positive symptoms are additions or changes to the behaviour of a patient, whereas negative symptoms are removals from the character or personality of the patient:

  • first-rank symptoms include hearing voices and believing that others are guiding you, for example – these are positive symptoms such as hallucinations and delusions, they are added to the patient’s behaviour as they were not there before the disorder became active
  • second-rank symptoms include flattened emotions and other negative symptoms, such as lack of energy, sex drive, etc (so these are all removals from the personality) – these often start well before the positive symptoms and any diagnosis, in what is known as the prodromal period


The features of a disorder are aspects about how a disorder develops and consider the disorder on a wider scale, often include facts and statistics. The key features of schizophrenia include:

  • schizophrenia appears to be a universal disorder (the condition can affect anyone in any place, males and females)
  • the profile of sufferers seems to be as follows:

– ¼ of patients will have one episode of schizophrenia and then fully recover
– ¼ of patients will suffer chronic schizophrenia, having continuous schizophrenic episodes
– ½ of patients will have occasional schizophrenic episodes but do not have a chronic disorder

  • positive symptoms (those added to the sufferer’s being) can be overcome (e.g. hallucinations, delusions), whereas the
  • negative symptoms (those lacking in sufferers) tend to remain
  • male sufferers tend to experience a more severe course of the disorder than females (Goldstein, 1988)
  • there are five categories which psychiatrists and diagnosticians use to describe different types of schizophrenia

Types of schizophrenia

One feature of the disorder is that there are different types. These subtypes have recently been ditched by the DSM-V, but it used to include (the European ICD-10 still include these, plus two more):

  • paranoid schizophrenia is when the patient is suspicious of others (delusions of being watched or followed are common, and thinking that messages in TV and radio programmes or newspapers are aimed directly at them) and common symptoms are delusions of grandeur and hallucinations
  • disorganised schizophrenia is when the patient’s speech is hard to follow and behaviour may be bizarre, acting with inappropriate moods for certain situations, although there are no delusions or hallucinations
  • catatonic schizophrenia is when the patient becomes very withdrawn and isolated and has little physical movement, they appear to be in a trance-like state, with very little speech or activity
  • residual schizophrenia is when there are low-level positive symptoms but there are psychotic symptoms present
  • undifferentiated schizophrenia is when the patient does not fit any of the four above types


Extension Resources

Here are some great videos and TED Talks introducing schizophrenia.