You need to be able to describe, evaluate and compare TWO biological explanations of schizophrenia. One of them MUST be the functioning of neurotransmitters (the "Dopamine Hypothesis"), so you need to know this in detail and the Exam could ask your specifically about neurotransmitters. The Specification also mentions genes and mental health, so the second explanation here is a genetic one. You could be asked for "a biological explanation of schizophrenia OTHER THAN NEUROTRANSMITTERS" or "how genes affect mental health" (with specifying schizophrenia).

NON-BIOLOGICAL EXPLANATIONS FOR SCHIZOPHRENIA

The Unit 2 Exam expects you to know about one non-biological explanation of schizophrenia. This page with consider cognitive explanations and Freudian (psychodynamic) explanations.

You are also expected to understand a psychological treatment for schizophrenia which is linked to this explanation.
As part of Clinical Psychology, you will look at Bradshaw's case study of Carol, which claims that there is a cognitive aspect to schizophrenia and that the disorder can be treated with counseling.
In this 15 minute video, Eleanor Longden describes her voices and therapy from a cognitive perspective (and the Recovery Model)

WHAT ABOUT FREUD?

In Unit 1, students had to learn about Freud's psychodynamic theory and his views on aggression, development and individual differences. Some students might prefer to make use of this material here, as an alternative explanation of schizophrenia.

SCHIZOPHRENIA & FAULTY COGNITIONS
A BREAKDOWN IN SELF-MONITORING

Cognitive deficits are a key symptom of schizophrenia. However, 'faulty cognitions' might be responsible for a lot of the negative and positive symptoms of schizophrenia too. Faulty cognitions include poor attention and memory, difficulties with language and disorganised thinking. 
One of the most important cognitive theories of schizophrenia is attention deficit theory.

Christopher Frith (1979) argues schizophrenia is the result of a faulty attention system.
Preconscious thought (thought that occurs without awareness) contains a huge amount of information from our senses that would normally be filtered. If this filtering process doesn't happen, there will be sensory overload. Thoughts that would usually be filtered out as irrelevant or unimportant are noticed instead  and treated as more significant than they really are. Frith says this accounts for the positive symptoms of schizophrenia, such as hallucinations, delusions and disorganised speech.
David Hemsley (1993, 2005) suggests schizophrenia involves a breakdown in the relationship between memory and perception. People with schizophrenia have a disconnect between their schemas (expectations of certain situations) and what they actually hear and see. When they encounter new situations, their schemas are not activated. As a result, people with schizophrenia experience sensory overload because they do not know which aspects of a situation to attend to and which to ignore. It also means they struggle to predict what will happen next. Their poor integration of memory and perception leads to disorganised thinking and behaviour.

Schizophrenic symptoms boil down to a lack of self-monitoring; thoughts and ideas are attributed to external sources (such as hallucinations), or result in delusions because the individual does not realise that they are self-generated. They mistakenly regard their own thoughts as alien and coming from someone else. PET scans of people with schizophrenia show under-activity in the frontal lobe of the brain, which is linked to self-monitoring.
The "schizophrenia simulator" gives a vivid insight into the consequences of problems with attention

FREUD'S PSYCHODYNAMIC EXPLANATION

In Unit 1, you studied Freud as an alternative to the biological explanation of aggression. You could use his ideas again as an alternative to biological explanations of schizophrenia.
According to Freud's psychodynamic approach, abnormality is caused when trauma from unresolved conflict between the id, ego, and superego is repressed into the unconscious. This causes fixation or  regression to an earlier stage of psychosexual development. If the ego is not fully developed, the individual may be dominated by the id or the superego, and will lack a sound basis in reality.

This might happen if someone experienced a very harsh childhood, perhaps because their parents were cold and unsupportive. The child becomes fixated or regresses to an earlier stage of development that was safer or more comforting.

Schizophrenia is linked to the oral stage; in particular, a stage called primary narcissism during which the ego has not separated from the id. Because the ego is the rational part of the mind, if you regress to a stage before it forms. you will stop operating on the reality principle and lose touch with reality. This explains some of the symptoms of schizophrenia, especially hallucinations, delusions and disorganized thought and speech.
Freud's view boils down to the idea that, in the face of fear and loneliness, a child retreats into itself, living in "a world of its own" because they find the outside world too threatening.

APPLYING FAULTY COGNITIONS TO REAL LIFE
AO2

Cognitive explanations of schizophrenia suggest cognitive therapies to address the "faulty cognitions". People with schizophrenia can learn to recognise faulty cognitions and either ignore them or cope with them.

The patient (client) talks about their experiences with their therapist. Working together, the client and  therapist develop a model of what’s causing the psychotic episodes. These factors vary from person to person. someone who hears upsetting voices will be helped to understand what’s triggering these voices. They can develop a more confident relationship with them, learning to ignore them at times so they can function in social situations.

The most popular therapy is Cognitive Behavioural Therapy (CBT). This was the therapy studied in Bradshaw's case study of Carol.

APPLYING THE PSYCHODYNAMIC EXPLANATION

Freud was the psychologist who pioneered the idea of the "talking cure" which he called psychoanalysis. However, psychoanalysis is different from normal cognitive therapy.

The psychodynamic explanation suggests that the causes of schizophrenia are buried in the unconscious mind, in memories of a distressing childhood. The client has created the symptoms of schizophrenia to protect themselves from these memories. So there's no point in just asking the client for their opinion about their illness.

Instead, the psychoanalyst tries to guide the client towards insight and self-knowledge. This might involve techniques like free association or the Rorschach inkblot test.

Art therapy is often used with people who have schizophrenia. If the client paints, they may be able to express what is wrong with them much better than they can in words. This helps with psychoanalysis, because the paintings may contain clues to the unconscious mind, but it also helps the client get rid of stress and anxiety, which tends to reduce the severity of symptoms too.
Schizophrenic art. Cognitive therapy may use the art-approach too, but it will focus more on stress-reduction and communication, less on finding secret messages in the artwork that reveal the workings of the unconscious mind.

EVALUATING COGNITIVE EXPLANATIONS
AO3

Credibility

Cognitive explanations account for many of the positive symptoms of schizophrenia as well as the cognitive deficits. By offering simpler underlying problems in place of a range of seemingly-unconnected symptoms, the cognitive explanation offers a more valid understanding of schizophrenia.

Much of the research into cognitive explanations is scientific and replicable. For example, McGuigan (1966) found that the vocal cords of patients with schizophrenia were tense during the time they experienced auditory hallucinations. This suggests that they were mistaking their own inner speech for someone else's voice.

Cognitive theories of attention and perception are well-established and backed by scientific research. Freudian theories are less scientific and more controversial.
Objections

The faulty attention system and self-monitoring explanation accounts for the positive symptoms of schizophrenia but not the negative symptoms.

It is not clear whether the cognitive dysfunction is a cause or effect of the disorder. This is another case of building a theory on an observed correlation between thought processes and symptoms, but correlations do not prove cause.

Many brain-damaged patients have problems with attention or with the relationship between memory and perception - for example, H.M. and the patients studied by Schmolck et al.. However, although these patients have cognitive deficits, they don't show the symptoms of schizophrenia. This challenges the cognitive explanation.

Other factors influence the development of schizophrenia that don't have anything to do with cognitive deficits. Genetic factors, stressful life events, and poverty play a part in the disorder, but it's not clear how these link to cognitions.

Freudian psychodynamic explanations have been criticized for not having any experiments to support them, being subjective, unreliable and unscientific.
Differences
The cognitive explanation by itself isn't a complete explanation. It could be said to DESCRIBE schizophrenia in more depth without really EXPLAINING where it comes from, why some people have these problems but others don't. A similar criticism applies to the Dopamine Hypothesis.

On the other hand, the cognitive explanation fills some gaps in the biological approach. For example, biological psychologists notice that even if dopamine levels are corrected by using drugs, it still takes days or weeks for positive symptoms to fade. This could be because faulty self-monitoring and poor attention carries on as a sort of "bad habit" even when dopamine activity is normal.

Cognitive explanations aren't offered as an alternative to biological explanations of schizophrenia. The two types of explanations are COMPLEMENTARY - they work together. For example, Frith (1992) found that cognitive deficits are linked to abnormalities in areas of the brain that use dopamine, especially the prefrontal cortex. He showed that people with schizophrenia have reduced blood flow to these areas (indicating reduced brain activity) during certain cognitive tasks. Since the prefrontal cortex handles attention and self-monitoring, this evidence supports both biological AND cognitive explanations.
Applications

The appeal of cognitive therapy is that it can be used by patients who want to reduce or refuse antipsychotic medication. Morrison et al. (2014) found that drop-out rates for the cognitive therapy were lower than drug therapy. Cognitive therapy was just as effective at  reducing the symptoms of psychosis.

The cognitive explanation is often used by people who advocate the Recovery Model. This perspective encourages people who hear voices not to think of themselves as "sick" and silence their troubling thoughts with drugs, but instead to understand the voices better and learn coping strategies to live with them. An example of this is the "Hearing Voices Movement" supported by Eleanor Longden (see the TED video):
Psychoanalysis is more controversial. It takes longer than cognitive therapy and, unlike cognitive therapy, you can't be sure it is working because the unconscious can't be observed or measured. However, Rosenbaum et al. (2012) compared people with schizophrenia being treated with psychoanalysis with those being given conventional treatment over two years; the psychoanalysis group improved far more than the control group, improving their social functioning and showing decreases in symptoms.

EXEMPLAR ESSAY
How to write a 8-mark answer

Assess the value of a non-biological explanation of schizophrenia for treating people with schizophrenia. (8 marks)
  • A 8-mark “evaluate” question awards 4 marks for describing explanations and treatments for schizophrenia from a non-biological perspective (AO1) and 4 marks for evaluation (AO2). You need a conclusion to get a mark in the top band (7-8 marks).

Description
Cognitive explanations suggest that many symptoms of schizophrenia are caused by simple underlying problems with memory, perception and attention.
Frith's attention deficit theory suggests people with schizophrenia get overloaded by information because they can't filter everything that's happening around them.
Hemsley's schema theory agrees with Frith but adds that people with schizophrenia struggle to integrate memory and perception. Without schemas, they don't know what to focus on and what to ignore.
These theories suggest that schizophrenics get confused between self-generated experiences (their own thoughts and imagination) and external experience (information coming to them through the 5 senses).

Evaluation
Cognitive therapy helps people with schizophrenia improve their memory and attention. It is better than drug therapy because it doesn't have side-effects.
Morrison et al. (2014) found that drop-out rates for the cognitive therapy were lower than drug therapy.
However, cognitive explanations don't account for negative symptoms and cognitive therapies might not help with these.
A practical problem is that most cognitive therapies involve talk, but speech is something people with schizophrenia have particular problems with, which makes it difficult for them to make use of therapy.

Conclusion
Cognitive therapies can be mixed with drug therapy for maximum effect, as shown by Bradshaw's case study of Carol, who benefited from CBT.

  • Notice that for a 8-mark answer you don’t have to include everything about cognitive explanations and treatments. You will notice I haven't mentioned the Freudian approach at all. But it is a balanced answer - one half description and one half evaluation.