Explanations for schizophrenia

Question 1

What is the genetic basis of the biological explanation?

Answer 1

-Family studies have confirmed that the risk of schizophrenia increases in line with genetic similarity to a relative with the disorder.
-Although the families share the same environment, so the correlation provides evidence for both, family studies give support for the genetic importance in schizophrenia.

Question 2

Gottesman and Sheild 1982?

Answer 2

A large scale family study, assessing the risk of developing schizophrenia.

Two parents= 46% compared to grandparents= 3.7%. Identical twin=48%.

In their twin study: MZ= 46% and DZ= 14%.

Question 3

What are the candidate genes involved in?

Answer 3

Early research looked into a single gene variant however it now appears multiple genes are involved.

These genes would most likely be coding for dopamine production.

Question 4

Candidate genes: Ripke et al?

Answer 4

Ripke et al (2014) combined all the data for previous genome wide studies and compared 37000 people with schizophrenia and 113000 controls. 108 separate genetic variations were associated with increased risk of schizophrenia.

Question 5

What is the role of mutation in the biological explanation?

Answer 5

Schizophrenia can have genetic origin in the absence of a family history, due to mutation.
This can be caused by radiation, poison and viral infection.
Brown et al found a positive correlation between risk of schizophrenia and parental age (risk of sperm rotation).

Question 6

Strengths of the genetic explanation: research support?

Answer 6

as well as family and twin studies, Tienari et al 2004 showed children with biological parents with schizophrenia were still at increased risk even when growing up with an adoptive family. A recent twin study Hilker et al 2018 found a 33% MZ rate and a 7% DZ rate.

Question 7

Strengths of genetic explanations: twin studies?

Answer 7

The Concordance rate is 3 times as much for genetically identical twins. This suggests a genetic predisposition.

Question 8

Strengths of the genetic explanation: application?

Answer 8

Genetic counselling- the process of investigating individuals and families affected by or at risk of genetic disorders to help them understand and adapt to the medical, psychological and familial implications of genetic contributions to disease.

Question 9

Weaknesses of the genetic explanation?

Answer 9

There are small samples in the studies.

Higher MZ rates could be explained by environmental factors.

Environmental factors- There is clear evidence for environmental factors. These include smoking cannabis at an early age, complications in birth, childhood trauma. Morkved et al found that 67% of schizophrenia patients had experienced one childhood trauma, compared with 33% of non-psychotic patients.

Question 10

What is the neural explanation?

Answer 10

-Scientists have found neural correlates for schizophrenia.
-The best known is the dopamine hypothesis:

Question 11

What was the original dopamine hypothesis based on?

Answer 11

Based on the discovery that drugs used to treat schizophrenia (antipsychotics) produced side effects similar to symptoms of Parkinson’s disease. Parkinson’s is associated with low dopamine levels.

Question 12

What is the dopamine hypothesis?

Answer 12

Therefore it was hypothesised that schizophrenia was caused by high levels of dopamine in subcortical areas of the brain.
Post mortem examinations showed excessive dopamine receptors , also shown in PET scans.

Question 13

What is the updated 1991 dopamine hypothesis?

Answer 13

Davies et al proposed the addition of abnormally low dopamine levels, which can explain some schizophrenia symptoms (low DA in prefrontal cortex leads to cognitive problems).
It has also been suggested that hypodopaminergia leads to hyperdopaminergia.

Question 14

What does the updated dopamine says about explaining dopamine levels?

Answer 14

The current dopamine hypothesis tries to explain the origin of these abnormal levels. It seems both genetic and psychosocial risk factors are linked to hypo/hyperdopaminergia.

Question 15

Strengths of the neurochemical explanation?

Answer 15

Evidence- Curran et al 2014 showed amphetamine drugs increase dopamine levels and also worsen symptoms in people with schizophrenia and induce them in people without. Also antipsychotics that reduce dopamine reduce symptoms. Thirdly, some candidate genes are involved in dopamine production. This suggests dopamine is involved.

Question 16

Weaknesses of the neurochemical explanation: glutamate?

Answer 16

post mortem and live scanning have consistently found increased glutamate neurotransmitter levels in schizophrenic brains and several of the candidate genes are involved in glutamate production. So there may be other neurotransmitters.

Question 17

Weaknesses of the neurochemical explanation: oversimplistic?

Answer 17

it is over simplistic to assume just because antipsychotics block dopamine receptors and then reduce symptoms, that this is the cause. Neurotransmitters interact with each other so others may be involved.

Question 18

Weaknesses of the neural chemical explanation: other drugs?

Answer 18

Apomorphine increases dopamine levels but does not induce schizophrenic symptoms.

Question 19

Neural anatomical explanation: limbic system?

Answer 19

Located in the subcortex and includes the hippocampus and amygdala.

Post mortems have shown significant cell loss in the limbic system and unusual connections in the hippocampus.

Question 20

Neural anatomical explanation: corpus callosum?

Answer 20

There are gender differences in normal brains and these are reversed in schizophrenic brains.

Question 21

Neural anatomical explanation: abnormal early development?

Answer 21

Early brain development in the 3rd trimester leading to disordered organisation of synapses.

Question 22

Neural anatomical explanation: brain imaging studies?

Answer 22

Showed reduced brain tissue, enlarged ventricles and under activity in the temporal frontal lobes compared to normal brains.

Question 23

Strengths of the neural anatomical explanation?

Answer 23

Research is highly reliable due to high control with specialist high tech equipment.
Suddain et al 1990 used MRI scans to obtain the brian structures of MZ twins where one had schizophrenia and the other didn’t. The twin with schizophrenia generally had enlarged ventricles and a reduced anterior hypothalamus. Supports brian differences.

Question 24

Weaknesses of the neural anatomical explanation?

Answer 24

Biological determinism- the issue of causation, is a person doomed because of their brain structure and it is hard to identify cause and effect with brain scans.

Question 25

Who proposed the schizophrenogenic mother theory?

Answer 25

Fromm-Reichman 1948 proposed a psychodynamic explanation because many of her patients had similar parents and childhood experiences.

Question 26

What is the schizophrenogenic mother?

Answer 26

The schizophrenogenic mother is cold, rejecting, controlling and creates a family situation of tension and secrecy.
This leads to distrust that develops into paranoid delusions.

Question 27

Who proposed the double bind theory?

Answer 27

Bateson et al 1972 agreed that family climate is important and emphasised the importance of communication style in a family.

Question 28

What is the double bind theory?

Answer 28

It happens when a child is trapped in a situation where they want to avoid wrongdoing, but there are mixed messages about what this is, and they are unable to comment on the situation and receive clarity. When they behave wrongly, they are punished by the withdrawal of love.

Question 29

What is an example of double bind theory?

Answer 29

a mother tells a daughter/son they aren’t affectionate enough but when the child shows affection the mother pushes them away.

Question 30

Who is particularly affected by double bind theory?

Answer 30

Small children have particular difficulty as they cannot leave the relationship because they are so dependent on their parents.

Question 31

How does double bind theory lead to schizophrenia symptoms?

Answer 31

It creates a confused and dangerous outlook on the world and an internal state of conflict, prevents the development of a coherent construction of reality.

Question 32

What is expressed emotion?

Answer 32

=The level of negative emotion expressed towards the person with schizophrenia, often by carers and family members.

Question 33

What do high levels of EE cause?

Answer 33

can worsen the prognosis in patients and increase the likelihood of relapse.
-Has been suggested this is part of the diathesis stress model to trigger the onset of schizophrenia, not just relapse.

Question 34

What are the three elements of expressed emotion?

Answer 34

1) Hostility- includes anger, blaming problems in the family on the patient and rejection. 2) Critical comments- occasionally accompanied by violence. 3) Emotional overinvolvement- showing lots of concern and pity which makes the patient feel guilty.

Question 35

How is expressed emotion measured?

Answer 35

Measured using the Camberwell Family Interview which records the relatives’ speech and attitude towards the patient.

Question 36

Strengths of family dysfunctions?

Answer 36

Evidence supports the link between dysfunctional relations and schizophrenia-

Read et al 2005 suggested adults with schizophrenia were more likely to have an insecure attachment type (C or D). Also reported 69% of men and 59% had a history or physical/sexual abuse.
Morkved et al 2017 showed 67% of people with schizophrenia suffered at least one traumatic event. Strongly suggests family dysfunction is involved.

Question 37

Weaknesses of family dysfunctions?

Answer 37

-No evidence to support specific double bind theory and schizophrenogenic mother.

-The research is socially sensitive as we must ensure we don’t parent blame, as this adds insult to injury.

Question 38

What are cognitive explanations?

Answer 38

Schizophrenia is caused by faulty information processing and faulty thinking.

Question 39

What is dysfunctional thinking?

Answer 39

-Disruption to normal thought processes.

Question 40

What are specific associations of dysfunctional thinking?

Answer 40

-Thought to occur through reduced processing in the ventral striatum which is associated with negative symptoms.
-Hallucinations are associated with reduced processing in the temporal and cingulate gyri.
-Indicates that cognition is impaired.

Question 41

What is metarepresentation?

Answer 41

the ability to reflect on thoughts and feelings and allows insight into our own behaviours, also allowing us to interpret the behaviours of others.

Question 42

Meta representation dysfunction:

Answer 42

Frith et al 1992.

A dysfunction disrupts the ability to recognise our own action as carried out by ourselves rather than by ourselves.

This explains hallucinations and delusions by insertion (the experience of having thoughts placed there by someone else).

Question 43

What is central control dysfunction?

Answer 43

Frith et al 1992.
Cognitive ability to suppress automatic responses is also dysfunctional.
Speech poverty and thought disorder stems from being unable to suppress automatic thoughts and speech triggered by thoughts.
People with schizophrenia tend to experience the derailment of thoughts because each word triggers associations that they are unable to repress.

Question 44

Strengths of cognitive explanations?

Answer 44

Evidence- Stirling 2006 studied individuals with schizophrenia and their cognitive abilities using the stroop test. Participants had to suppress the tendency to say the word and not the colour or it. As Frith’s central control dysfunction theory predicted, the people with schizophrenia took longer to name the colours. So cognitive ability is impaired in those with schizophrenia.

Question 45

Weaknesses of cognitive explanations?

Answer 45

Proximal explanation- this explanation focuses on what symptoms are currently. They do not focus on the distal explanations, what caused the symptoms in the first place. Therefore is only a partial explanation. Distal explanations, like biological or dysfunctional families, do exist.

Question 46

What is the interactionalist approach?

Answer 46

A way to explain schizophrenia in terms of a combination of psychological and biological factors and these factors interact with each other.

Question 47

What is the diathesis stress model?

Answer 47

An interactionist approach linking biological vulnerability to environmental stressors.
Both are necessary to trigger the disorder.

Question 48

What was the original diathesis stress model so schizophrenia?

Answer 48

The original model (Meehl’s) diathesis was entirely genetic, one schizogeny. If the person experiences stressors such as schizophrenogenic mothers, this results in the development of the disorder. According to Meehl, if the person did not possess the gene, then no amount of stress will trigger the disorder.

Question 49

What is the modern understanding of diathesis?

Answer 49

It is now clear that many genes are associated with schizophrenia.
Modern diathesis factors also included psychological trauma (Ingram and Luxton 2005).
Read 2001 proposed a neurodevelopmental model, adding altered early brain development as a diathesis, caused by severe trauma.

Question 50

What is the modern understanding of stress?

Answer 50

In the original model stress was seen as psychological and mainly due to parenting.
The modern model includes any factors linked to risk of schizophrenia. (Houston et al 2008). Most recently, cannabis use has been identified as a risk factor, because it interferes with the dopamine system. It increases the risk of schizophrenia up to 7 times per dose.

Question 51

How is the diathesis stress model applied to treating schizophrenia?

Answer 51

Combining antipsychotic drugs with CBT.
Turkington et al 2006 pointed out it is possible to believe biological influences and still practise CBT.

Question 52

What are the differences between countries in terms of the interactionalist approach?

Answer 52

Combined treatment is quickly becoming the standard treatment in Britain. However in the US, they have been slower to adopt the interactionist approach and there is still a conflict between biological and psychological explanations.

Question 53

Strengths of interactionalist: research support?

Answer 53

Tienari et al 2004 carried out a study on 1900 Finnis children adopted away from biological mothers with schizophrenia. They also assessed the parenting style of the new families. In adulthood the genetic risk children were compared to a control group. It was found that high levels of criticism and conflict were strongly associated with development of schizophrenia, but only in the genetic risk group.

Question 54

Strengths of interactionalist: real world application?

Answer 54

combination of treatments. Tarrier et al showed combining treatments increases effectiveness. Participants in the combination group showed lower symptoms than the medication only and therapy only groups.

Question 55

Weaknesses of interactionalist approach: causation fallacy?

Answer 55

Jarvis and Okami 2009 criticised Tarrier et al and state there is a treatment causation fallacy. It is not always logical to suggest that just because something is successful in treating a disorder, it justifies a particular explanation. So we cannot automatically assume the interactionist approach is correct just because combination treatments are successful.W

Question 56

Weaknesses of interactionalist: over simplified?

Answer 56

The original diathesis stress model is too simplistic, as we know there are multiple biological associations, as well as multiple genes. We also have identified many more risk factors in the environment. This supports the modern understanding but this was based on the over simplified model.