Schizophrenia

Define schizophrenia

A severe mental illness where contact with reality and insight are impaired. It is an extreme example of psychosis.

Positive symptoms of schizophrenia

Delusions, hallucinations and disorganised speech

Negative symptoms of schizophrenia

Flattened effect, reduced speech and a lack of initiative

What are delusions and the two types?

Fixed false beliefs can be paranoid or grandiose

What are hallucinations and their two types?

Seeing or hearing things that aren't real, can be visual or auditory

What is flattened effect as a symptom?

Not feeling strong emotions

How is SZ diagnosed?

ICD requires 2 symptoms, can be +/-
DSM requires 2 symptoms, can’t be 2 -

2 potential issues in SZ diagnoses 

comorbidity and symptom overlap 
gender and cultural bias

Limitations of SZ diagnosis

Rosenhan’s 1973 study undermined system as no psudopatients were identified
Cheniaux 2009 study found 68% diagnosed using ICD and 39% using DSM (unreliable)

Strengths of SZ diagnosis

OPCRIT - a operationalised checklist of SZ symptoms has improved diagnosis
Osorio found 0.97 inter-rater observability and 0.93 test-retest reliability using DSM

Concordance rates for SZ

MZ: 48%

DZ: 17%

Candidate gene research

Ripke (2014) meta-analysis found 108 genetic variations that are more prevalent - SZ is polygenic

Finnish adoption study findings

7% of 112 adoptees taken away from mother with SZ by the age of 4 later developed SZ compared to 1.5% control group of adoptees

4 dopamine hypotheses for SZ

SZs brain produces more dopamine than normal
Abnormally high number of D2 receptors
Hyperdopaminergia in Broca’s area associated with positive symptoms
Hypodopaminergia in prefrontal cortex associated with negative symptoms

How do anti psychotic drugs work

Blocking D2 receptors, reducing dopamine reuptake, reducing symtoms

What is tardive dyskenesia

Incurable, degenerative disease which can be caused by taking anti psychotic drugs for a long-term period

Other neural correlates for SZ

Glutamine activates neurons and brain cells
Low serotonin associated with negative symptoms 

Limitation of neural correlates

They don’t establish causation, could be a symptom

3 environmental factors for SZ

Birth complications (Morgan 2017)

Childhood trauma (Morkved 2017)

Smoking high THC cannabis (Deforti 2015)

Family dysfunction as an explanation for SZ

Reichman (1947) noticed many patients spoke of a schizophreniogenic mother who was cold, harsh and critical

Bateson et al (1972) points to a poor family communication style with double binds which confuse the child

Highly expressive emotional families create a critical, aggressive and stressful environment thought to trigger psychotic episodes

What are 3 double binds?

contradicting messages from each parent
saying one thing while expressing the opposite

no-win situations where doing the thing you were told to do gets punished

dysfunctional thought processing as an explanation for SZ

Frith (1992) identified two kinds: poor metarepresentation and poor central central control

What is poor metarepresentation?

Not being able to reflect on thoughts, leading to a lack of insight

What is poor central control?

Not having the ability to suppress automatic thoughts

Strengths of psychological explanations for SZ

Read et al (2005) 69% of women and 59% of men with SZ have a history of physical/sexual abuse. SZ sufferers also have disproportionate level of insecure

attachment.

Berger (1956) SZ patients reported higher recall of double bind statements than non-sz patients

Brown (1958) SZ patients returning to high EE families have higher relapse rates

Stirling et al (2006) found SZ group took over twice as long on the stroop test.

Limitations of psychological explanations for SZ

Parent blaming is socially sensitive
Reports of childhood abuse and double binds may be part of delusions

Ignores evidence for biological causes.

Dysfunctional central control could be symptom of SZ rather that its cause.

Most common drug treatment for SZ?

Anti-psychotic dugs which are all dopamine antagonists

What do agonist drugs do?

increases the action of a neurotransmitter

What do antagonist drugs do?

blocks/reduces the action of a neurotransmitter

What are typical antipsychotics?

dopamine antagonists only by blocking D2 receptors, been around since 1950s, e.g. chlorpromazine

What are atypical antipsychotics?

dopamine antagonists and serotonin agonists to treat both positive and negative symptoms, been around since 1970s, e.g. clozapine

Evaluate typical antipsychotics

+Effective on reducing positive symptoms, Thornley (2003) meta-analysis found significant symptom reduction

- Serious side effects, 30% LT users develop TD, little effect on negative symptoms

Evaluate atypical antipsychotics

+Maltzer found it was effective on 30-50% of typical non-responders, works on both symptom types, less steroid side effects

- Worries of dependancy and only suppressing symptoms not treating

Family therapy as a treatment

Aims to improve communication and interaction between family members to sort out family dysfunction, involves psycho education and therapeutic alliance

CBT as a treatment

Involves psycho education, motivational interviewing, disputing delusions and mindfulness

Token economies as a treatment

Used in wards, used for those with maladaptive behaviour, dosnt cure but improves quality of life

Evaluative points about token economies

Helps psychiatric wards become calmer environments → more of a benefit to staff?

Helps maintain positive behaviours → only temporary effect

Can help encourage other treatments → not a cure, just a measure

Research supporting family therapy

McFarlane (2016) found that family therapy for SZ was ‘consistently effective’ and reduced relapse rates by 50-60%

Research supporting CBT

Juahar (2004) conducted a meta-analysis of 34 studies and found that there was clear evidence for a small but significant effect on both positive and negative symptoms

Research supporting token economies

Glowacki (2016) found a decline in negative symptoms and unwanted behaviours using token economies

What is the diathesis-stress model for SZ?

Idea that both biological and psychological factors are necessary to develop SZ, considering the interaction of nature and nurture

What was proposed in the first distress-stress model in 1962?

Meehl proposed that a theoretical schizogene was the diathesis and a schizophrenogenic mother was the stressor

Tarrier’s research and findings

into internationalist approach to treatment

randomly allocated 315 participants to anti-psychotics + CBT/counselling and a control group

experimental conditions showed significant improvements compared to the control