This mental disorder is compulsory so every candidate learns it and the Examiner will expect you to know it in detail. The Specification identifies HALLUCINATIONS, DELUSIONS, THOUGHT INSERTION and DISORDERED THOUGHTS in particular, so you could be asked about these. Make sure you understand the difference between the FEATURES of schizophrenia (how common it is, what sort of people develop it?) and the SYMPTOMS (what thoughts or behaviours do people with the disorder show?).

SCHIZOPHRENIA

In Unit 2, Clinical Psychology expects all students to know about schizophrenia, its features and symptoms as well as different explanations and treatments.
People with schizophrenia often have an altered perception of reality. They may see or hear things that don’t exist, speak in strange ways, believe that others are trying to harm them or feel like they’re being constantly watched (paranoia). This can make daily life difficult, so people with schizophrenia may withdraw from the outside world or act out in confusion. Schizophrenia is a chronic disorder, meaning that once you have it, it does not go away. However, with support, medication and therapy, many people with schizophrenia can function independently and live fulfilling lives.
Stop right there!

Let's clear something up.

A lot of people think schizophrenia is the same as having multiple personalities. IT ISN'T! Schizophrenia is nothing to do with multiple personalities. So forget about all those schizophrenia/multiple-personality jokes..

Not only are these jokes DUMB, they're also JUST PLAIN WRONG!
This excellent booklet from the National Institute for Mental Health gives a thorough but concise summary of schizophrenia. The video at the bottom of this page features schizophrenia sufferers talking about their condition.
NIMH Schizophrenia Booklet.pdf
File Size: 1082 kb
File Type: pdf
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FEATURES OF SCHIZOPHRENIA
THE SHATTERED MIND

If the Examiner asks for "features" of schizophrenia, you should describe its types, statistics and the people it affects. Do NOT describe symptoms. The Exam will ask about symptoms in a separate question.
Schizophrenia means "split (or shattered) mind". Not 'split' in the sense of having different personalities, but split in the sense of being cut off from reality and self-knowledge.
Schizophrenia is one of the more common mental disorders. 1% of the population will be affected by it in their life. Symptoms usually appear in early adulthood. It affects men and women equally, but the symptoms usually appear earlier in men (teens) and later in women (20s or 30s).

A quarter of people with schizophrenia suffer one episode but then recover; another quarter do not recover and have the symptoms for the rest of their lives. Half of people with schizophrenia can, with treatment, go through periods without symptoms but the symptoms recur.
ICD-10 codes schizophrenia as F20 and lists 7 types of schizophrenia.

Paranoid schizophrenia (F20.0) is the most common type, tending to develop later and having more positive symptoms. Hebephrenic (or disorganised) schizophrenia (F20.1) develops earlier and involves confused emotions. Catatonic schizophrenia (F20.2) is very rare and sufferers are motionless and silent. Undifferentiated (F20.4) is a mixture of symptoms of the other types. Simple schizophrenia (F20.6) is rare and features only negative symptoms.
DSM used to include similar types of schizophrenia but DSM-5 has replaced them with a single category: schizophrenia spectrum disorders. This is because schizophrenia features a range (spectrum) of symptoms which are not fixed but might change over time.

FAMOUS PEOPLE WITH SCHIZOPHRENIA

Brian Wilson - founded the Beach Boys, wrote Good Vibrations
John Nash - Nobel Prize-winning mathematician, subject of A Beautiful Mind (2001)
Vivien Leigh - Oscar-winning actress, played Scarlet O'Hara in Gone With The Wind (1939)
Vincent Van Gogh - Dutch artist, painted Sunflowers, appeared in Doctor Who
Jake Lloyd - actor, played Young Anakin Skywalker in The Phantom Menace (1999)
Joey Ramone - punk rock icon, lead singer in The Ramones
The 2001 film A Beautiful Mind stars Russell Crowe as John Nash. It plays tricks with the audience and takes liberties with history, but it gives some insight into the positive symptoms of schizophrenia and the problems with therapy - as well as being a great film.

The idea of schizophrenia as a 'beautiful' condition is also suggested in Don McLean's Vincent - a song tribute to Vincent Van Gogh.

SYMPTOMS OF SCHIZOPHRENIA
POSITIVE & NEGATIVE

Symptoms are the behaviours and thoughts by which a mental disorder is diagnosed. They are distinct from the features of schizophrenia (above). Make sure you understand which the Examiner is asking for.
The symptoms of schizophrenia are split into positive symptoms and negative symptoms. Some of the negative symptoms are also identified as cognitive deficits.
POSITIVE symptoms are symptoms that schizophrenia ADDS to your experience of the world.
  • Hallucinations are when you see or hear things that aren't real. A common auditory hallucination is voices.
  • Delusions are false ideas you feel convinced are true. Common delusions include paranoia (the belief that people are watching you are want to hurt you), delusions of grandeur (the belief you are important, heroic or have super powers) and delusions of identity (thinking you are someone else, like Jesus Christ or Napoleon). Another delusion is thought insertion (the belief that your thoughts are not your own and have been put into your mind by someone else).
  • Disorganised thoughts, known as “thought disorder” or “loosening of associations”, is a key aspect of schizophrenia. Speech may become tangential (jumping from one topic to another apparently at random, or on the loosest of associations, or giving answers to unrelated questions). Speech may be highly circumstantial (speaking continuously, providing irrelevant details and never getting to the point). Speech can become so disorganized that it becomes a completely jumbled "word salad".
NEGATIVE symptoms are symptoms that schizophrenia TAKES AWAY from your experience of the world.
  • Speech problems may include the inability to speak at all (alogia)
  • Loss of emotions is a feeling of numbness (affective flattening) and may include a loss of facial expression too
  • Lack of motivation to begin things or carry on with tasks (avolition) - this often includes the inability to feel pleasure (anhedonia)
  • Social withdrawal includes breaking of friendships, quitting jobs, not making eye contact or responding to others (asociality)
Be careful. Positive symptoms aren't "nice" symptoms. In some ways, they're worse than the "negative" symptoms.
COGNITIVE DEFICITS are a type of negative symptom that involves the loss (deficit) or a mental ability:
  • Memory loss (amnesia)
  • Attention deficit includes being distracted
  • Planning difficulties include problems thinking about the future
  • Poor decision-making is linked to avolition

DIAGNOSING SCHIZOPHRENIA

Clinicians will ask about positive and negative symptoms. "Hearing voices" is a classic symptom but clinicians are cautious about diagnosing schizophrenia on that symptom alone. There are cultures where hearing voices is considered normal in some contexts (eg Caribbeans and bereavement).

Using ICD-10, the clinicians will try to place the client in one of the 7 types of schizophrenia. There are usually elements of each type of schizophrenia going on so it may be a case of "best fit" or else undifferentiated type schizophrenia (F20.4) may be diagnosed.  ICD-10 requires the symptoms to have been in evidence for one month.

Using DSM-5, the clinicians will look for delusions, hallucinations, disorganized speech and behavior, and
other symptoms that show dysfunction. The client must have TWO of these symptoms for a valid diagnosis (in previous editions, only one symptom was necessary so DSM-5 has made False Positives less likely but may have caused False Negatives). Symptoms must have been present for six months.
Schizophrenia is characterised by the person suffering psychotic episodes. During a psychotic episode, the symptoms (especially the positive symptoms) become very severe and prevent normal functioning. Often, it is a psychotic episode that leads a person to get diagnosed with schizophrenia that might have been going on for a long time previously. Episodes can last a few days or can go on until treated.

The main symptoms associated with a psychotic episode are:
  • hallucinations
  • delusions
  • confused and disturbed thoughts
  • lack of insight (the person cannot tell that their behaviour is inappropriate)
In ICD-10 there is a diagnosis of residual schizophrenia for individuals who still have schizophrenic symptoms (normally negative symptoms and cognitive deficits) but are non-psychotic.

EVALUATING THE DIAGNOSIS OF SCHIZOPHRENIA
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Credibility

Schizophrenia is a disorder that has been known about for a long time. Eugen Bleuler coined the word "schizophrenia" 1908 but it was known by other names before that. Schizophrenia has featured in every edition of DSM and in ICD since ICD-6. Its symptoms have been unchanged and, until DSM-5, both manuals categorised it in types (7 in ICD-10, 5 in DSM-IV). Many of schizophrenia's symptoms are highly visible and easily recognised, especially during a psychotic episode.

The introduction of diagnostic manuals has increased reliability of diagnosis over the years even though the manuals are not without flaws.

By moving to a definition of "schizophrenia spectrum disorders", the DSM-5 makes diagnosis more reliable and valid because clinicians are less likely to be "taken in" by the presence or absence of stereotypical symptoms (like hearing voices in the Rosenhan study).
Objections

Cooper et al. (1972)  asked American and British psychiatrists to diagnose patients by watching a number of filmed clinical interviews. The American psychiatrists diagnosed the patients to be suffering from schizophrenia twice as often as the British psychiatrists (who diagnosed them with depression). The same symptoms did not result in similar diagnosis in the two countries. This points towards problems of reliability as well as cultural differences in diagnosis.

However, this study was in the 1970s, before DSM-III improved the reliability of American diagnoses. Since then ICD and DSM have converged and offer similar definitions.

Schizophrenia isn't the only disorder that causes psychosis. For example, psychosis may be caused by brain tumours, strokes, epilepsy, syphilis and dementia. This creates problems with the valid diagnosis of schizophrenia because something else could be the real cause of psychotic behaviour.

Cultural differences interfere with valid diagnoses. Davison & Neale (1994) state that in Asian cultures, a person experiencing emotional disturbance is praised if they do not express their feelings. However, in some Arabic cultures, the outpouring of emotions is encouraged. A person from one of these backgrounds might be considered abnormal for showing or failing to show emotion by a clinician who doesn't understand the culture.

Thomas Szasz (1961) challenged the validity of schizophrenia. Szasz suggests it is merely an extreme version of normal behaviour. The diagnosis is used to label someone who finds modern society unbearable and can't live in it. Richard Bentall (1993) agrees that the diagnosis is too vague to be useful; he argues that we should abandon schizophrenia as a "catch all" classification and replace it with separate disorders for particular symptoms.
Differences
The DSM-5 has abandoned the different types of schizophrenia and this leads to different diagnoses, depending on which manual is being used.

ICD-10 requires symptoms to be evident for a month before diagnosis, but DSM-5 requires 6 months. This means a sick person is more likely to be diagnosed (and treated) quicker if ICD-10 is being used. However, this increases the risk of a False Positive, because lots of things can cause people to behave abnormally for short periods (stress, grief, drugs, etc.). DSM-5 is more valid, because the symptoms have to be in evidence for longer, but this could put a person in great distress or who can't look after themselves at risk.
Applications
In Bradshaw's case study, Carol was diagnosed using DSM-IV with undifferentiated type schizophrenia. Using DSM-5, she would just have been diagnosed with a schizophrenia spectrum disorder.

In Rosenhan's study, 7 of the pseudopatients were admitted with diagnoses of schizophrenia (despite only have auditory hallucinations that weren't "bizarre"); they were released with "schizophrenia in remission" on their case notes. This was not a DSM-II category. Residual schizophrenia was in DSM-II at the time, but that condition still involves non-psychotic schizophrenic symptoms, whereas the pseudopatients were completely healthy.

In Gottesman & Shield's twin study, the researchers used hospital notes (based on ICD-6) to diagnose schizophrenia, but also used their own psychometric tests and interviews.

In Kety et al.'s Danish-American adoption study, the psychiatrists used hospital notes (based on ICD-6) but Kety came up with his own classifications too. His classification of "schizophrenia spectrum disorder" wasn't in either DSM-I or ICD-6 at the time, but it's in DSM-5 today, so Kety was ahead of his time.