psychology schizophernia

What is schizophrenia?

A severe mental disorder affecting thinking, perception, emotions and behaviour, often involving a loss of contact with reality (e.g. hallucinations and delusions). Around 1% of the population is affected.

Is schizophrenia constant?

No — it is usually episodic, with periods of acute symptoms and periods of recovery.

Common misconception about schizophrenia?

What are positive symptoms?

Additions to normal behaviour.

What are delusions?

False beliefs held despite no evidence, e.g. Persecution → "people are watching me"; Grandeur → "I have special powers"; Nihilistic → "I don’t exist".

What are hallucinations?

perceptions that aren’t real e.g:

• Auditory voices (most common). Hearing voices that nobody else hears

• Tactile hallucinations: Lewandowski (2009) → ~20% experience (e.g. insects crawling).

• Visual: seing objects/people that aren;t there

What is disorganised thinking/speech

Speech; sentence becomes mixed up and difficult to understand→ word salad

Thinking: thoughts in their head that aren’t theirs belong to someone else (insertion)

What is avolition?

Lack of motivation to start/continue tasks.

What is flat affect?

Reduced emotional expression (monotone voice, no facial emotion).

Other negative symptoms?

Alogia → reduced speech; Anhedonia → reduced pleasure; Asociality → lack of social interest.

What is catatonic behaviour?

Displayed bodily movement e.g. repetitive movement, mimicking others

What system is used in the UK for diagnosing schizophrenia?

ICD-10 by World Health Organization.

Key diagnostic rule for schizophrenia?

At least 1 core symptom OR 2 others for 1 month+.

Examples of ICD symptoms?

Thought insertion/withdrawal; Hallucinatory voices; Delusions of control; Catatonia; Negative symptoms.

Strength of diagnosis systems?

Improves consistency + communication between professionals.

Limitation of diagnosis?

Subjective interpretation; Cultural bias; Overlap with disorders → reduces validity.

What does the dopamine hypothesis state?

Schizophrenia is linked to abnormal dopamine activity in the brain leads to symptoms of scz

Original version of the dopamine hypothesis?

Too much dopamine → causes psychosis.

Supporting study for dopamine hypothesis?

J. J. Griffith → found amphetamines which (increases dopamine) could induce symptoms e.g. halluncinations in individuals without szc (induced psychosis)

What is mesolimbic pathway?

Too much dopamine → positive symptoms e.g. halluncinations and delusions

Due to overstiumulation of areas linked to reward and emotion

What is mesocortical pathway?

Too little dopamine → negative symptoms e.g. avolition, reduced EE and cognitive impairement.

Strength of dopamine hypothesis?

Supported by drug evidence (antipsychotics reduce dopamine transmitter which can reduce positive symptoms e.g. hallucinations).

revised dopamine hypothesis- more efffective; allows theory to explain both postiive and negative symptoms allows full range of symptoms

Limitation of dopamine hypothesis?

Cause vs effect unclear; Cause/conseuqnece of it - may be scz itself or stress to change in dopamine

Reductionist (ignores environment); Drugs don’t work for all → incomplete explanation.

What are structural abnormalities?

Physical brain differences (e.g. enlarged ventricles).

Enlarged ventricles

• fluid filled spaces in the brain

• Weinberger et al: used CAT scans and found indiviudals with scz had larger ventricles than control with around 40% falling from normal range

• Supported b ANgerseason 1988 found ventricles were 20-50% larger using MRI scans

Cortical atrophy

• loss of neurons in celebral cortex

• Causes widening of the sulci & reduction in brain tissue- potentially affecting cog functioning

• Viva et al 1988: found 33% of individuals w scz showed moderate to severe atrophy

Reversed celebral asymmtery

• right hemisphere is larger than the left unlike typical brain strucure

• Luchins et al: foound more cases of this reversal in individuals without szc- particulary areas linked to language

• May explain symptoms e.g. disorganised speech

Strength of structural abnormalities?

Based on objective scientific methods: scans (MRI, CAT) → reliable. Provides physical and measurable data about brain structure

Helps explain cognitive & behavioural symptoms of szc e.g. loss of brain tissues in areas responsible for language→ disorganised speech & impaired thinking

Limitations of structural abnormalities?

Cause vs effect issue whether they cause disorder/ develop due to it: Mathalon et al suggests abnormalites may be both neurodevelopmental and neruodegenerative → weaknes exp

Found in other disorders e.g. bipolar (Roy et al) → low validity; Not all patients show abnormalities.

Key idea of psychodynamic explanation (Freud)?

• Schizophrenia = regression to oral stage due to stress as defence mechanism → weakened ego and dominant id → lose control with reality

• Creates alternative interal reality to cope with loss of reality

• Lead to halluncinations and delusions

Supporting case for psychodynamic explanation?

Daniel Paul Schreber.

What is the concept of a Schizophrenogenic mother?

Cold + controlling emotionally distant mothet causes insecurity that contributes to scz.

Strength of psychodynamic explanation?

Explains loss of reality (delusions/hallucinations). E.g. regression to infant stage sugegst ego weakened, id dominated and withdrawls from external reality. Can explain symptoms

Considers role of early experinces and unconscious processes

Limitations of psychodynamic explanation?

Not scientific (unfalsifiable); Based on single case → low generalisability; Blames mothers (socially sensitive); Not effective as treatment.

What does the cognitive approach focus on?

Dysfunctional though processing: problems processing infromatio in the brain →hallucinations

Key theory by Frith?

Metarepresentation dysfunction; Cannot recognise own thoughts → hallucinations.

What is central control dysfunction?

Cannot filter thoughts → disorganised speech.

What is attention deficit theory?

Too much information enters consciousness → overload.

Strength of cognitive explanation?

Supported by research evidenc: stirling et al (2006) found individuals with scz perfomed worse on cognitive tasks → having onger to supress automatic reponses (central control)

Provides detailed explonatory account of scz: Fith linked cognitive deficinet to underlying brain dysfunction→ supported by evidence

Limitation of cognitive explanation?

Doesn’t fully explain cause → best combined with biology explains symptoms occur due to fault thinking processes but not underlying cause of deficints

Cant explain all symptoms equally well: more effective in explaining positive symptoms but less on negagtive & beck cogntiive triad orginally for depression so application uncertain

What is double-bind theory (Bateson)?

Conflicting messages → confusion → schizophrenia.

Child unable to resolve this contradiction/question it leading them to view world as unpreditable and threatening

May result to paranoid delusions and disorganised thinking

What is expressed emotion (EE)?

• level of negative EE in families

• High criticism/hostility → increases relapse.

Supporting study for EE?

• Brown found individuals with scz more likely to relapse when living in high EE environemnts

• Vaughn & Leff (1976) → higher relapse in high EE homes.

Strength of dysfunctional families explanation?

Strong evidence for relapse (EE): Vaughn & Leff (1976) → higher relapse in high EE homes.

Practical evidence→ Pharoah et al found reducing EE through family intervention can lower relapse rates

Limitations of dysfunctional families explanation?

Cause vs effect (Liem, 1974);

Socially sensitive: Parent blaming; Not full explanation as individuals with scz may not have dyfunctional families.

What is urbanicity?

Higher schizophrenia rates in cities.

Supporting studies on urbanicity?

Zammit et al. (2002) → cannabis doubles risk; more common in city areas

What is social isolation?

Lack of support → symptoms worsen as no oen to challenge delusional thoughts

Study supporting social isolation idea?

Jones et al. (1994) → poor childhood relationships ↑ risk.

Key study on ethnicity & discrimination?

Cochrane → Afro-Caribbean groups more likely to be diagnosed due stress from discimination

Strength of sociocultural factors explanation?

Holistic — considers real-life factors important as scz doesnt develop in isolation→ increase validtity

Research support → zammit et al → increase validity as a supporting explaination

Limitations of sociocultural factors explanation?

Hard to isolate causes; Social drift hypothesis suggest individuals may move to urban areas due to developing scz rather than urban living causing scz

Lack precision→ many overlapping factors→ diffiuclut to identify→ more descriptive than explantatory

How do antipsychotic drugs work?

Block dopamine receptors → reduce positive symptoms.

Typical antipsychotics

• E.g. chlorpromazine: act as dopamine antagonists meaning they block dopamine receptors and reduce dopamine in the brain

• Help reduce both positive and negative symptoms

How are atypical antipsychotics different?

e.g. clozpamine and risperidone Affect dopamine + act on serotonin systems → reduce both positive and some negative symptoms

• clozpamine often used for treatment-resistant schizophernia but can cause serious side effects e.g. agranulocytosis meaning pateints must have regular blood tests

• Risperidone works at lower doses and may produce fewer side effects

Strength of antipsychotic drugs?

Thornley et al. (2003) → effective vs placebo; reduced symptoms effective in reducing positive symptoms

Meltzer (2012) → clozapine effective in 30-50% of patient who havent responded to other drugs for treatment-resistant cases- practical value

Limitations of antipsychotic drugs?

Side effects (e.g. neuroleptic malignant syndrome ); physical harm

Non-compliance → Rettenbacher found large proportional of patients don’t take their medication consisently- less effective in real life

What is CBT for schizophrenia?

Therapy helping patients understand and manage symptoms.

Key techniques in CBT?

Normalisation; Reality testing; Coping strategy enhancement (Tarrier).

Strength of CBT?

Jauhar et al. (2014) → small but significant improvements; NICE recommends CBT.

Limitations of CBT?

Mixed evidence (Neil Thomas, 2015); Not a cure → better with drugs (Kuipers).

Overall evaluation of explanations?

Biological → scientific but reductionist; Cognitive → useful but incomplete; Social → holistic but unclear cause. Best explained by diathesis-stress model.