Schizophrenia Flashcards
Schizophrenia
A psychosis - losing touch with/having a distortion of reality
What’s the incidence rate of sz across the world?
1:100 or 1%, and Fischer & Buchanan (2017) found that the ratio of men diagnosed with sz to women diagnosed with sz is 1.4:1
Positive Symptoms
Behavioural excesses that are rare in normal everyday life (e.g. hallucinations, delusions, disorganised behaviours/speech), generally respond well to drug treatment
Negative Symptoms
Behavioural deficits (the loss of behaviours that non-sz exhibit), can cause long-term consequences and are harder to treat as they’re less responsive to drug treatment
Hallucinations
A sense of perception not caused by an external stimulus: auditory, visual, olfactory, tactile, gustatory
Delusions
A false belief that is experienced without any evidence to support it - is usually very absurd & can’t be overcome by reason (e.g. persecution, grandeur)
Delusions of persecution
False belief that others are plotting against/trying to harm them
Delusions of grandeur
False belief that one has a power or is a famous person
Disorganised speech and/or thoughts
Problems with the organisation of speech and ideas, linked to ‘thought disturbances’ where an individual may appear incoherent
Disorganised behaviour
Unpredictable behaviour, either overly excited (catatonic excitement) or immobility (catatonic stuport)
Avolition
General loss of energy resulting in: lack of goal-motivated behaviour, inability to make decisions, reduced motivation, poor hygiene, social withdrawl
Speech poverty
Excessively brief replies with minimal elaboration, often with delayed responses
Flat affect
Absense of emotion and appearing lifeless, including staring vacantly and not making eye contact & speak in a flat tone
Whats are the 2 main classification systems used to diagnose mental illness?
DSM-5 & ICD-11
DSM-5 classification of sz
- Have to have at least 2 of: delusions, hallucinations, disorganised speech, disorganised behaviour & negative symptoms - one of which must be delusions, hallucinations or disorganised speech
- The level of functioning in everyday life has decreased significantly
- Continuous signs of disturbance for at least 6 months, which must include 1 month of symptoms
- Other disorders and substance abuse must be rules out
Test-Retest Reliability
Where the same clinician makes the same diagnosis on separate occasions based on the same info
Inter-Rater Reliability
Where different clinicians make the same diagnosis on the same patient
Reliability - Osario et al. (2019)
Used the DSM-5 to assess the reliability of the diagnosis of sz in 180 pps, pairs of interviewers achieved inter-rater reliability of +0.97, and test-retest reliability of +0.92, suggesting reliability of the diagnosis is very high.
Validity
The accuracy of the diagnosis
Reliability (according to validity)
A valid diagnosis must be first reliable to be valid, but this doesn’t always guarrantee validity.
Descriptive Validity
To be valid, symptoms of sz patients should be different than the symptoms of those with other disorders
Criterion Validity
To be valid, different assessment systems (e.g. DSM-5 & ICD-10) must reach the same diagnosis for the same patient
Validity - Cheniaux et al. (2009)
Had 2 psychologists assess the same 100 patients using the ICD-10 & DSM-IV. Using the ICD-10, 68 pp were diagnosed, while with the DSM-IV, only 39 were diagnosed
Co-morbidity
Refers to the presence of one or more additional disorders occurring simultaneously with schizophrenia
Co-morbidity - Reliability
The more co-morbid disorders an individual is diagnosed with, the less valid/reliable those diagnoses are
Co-morbidity - Validity
Patients may be diagnosed with the wrong disorder and receive incorrect treatment where degeneration can occur.
Co-morbidity - Buckley et al. (2009)
Reported that:
50% of sz had co-morbid depression,
47% had co-morbid substance abuse,
29% had co-morbid PTSD,
23% had co-morbid OCD,
15% had co-morbid panic disorder
Culture Bias
Tendency to over/under diagnose schizophrenia in certain cultural/ethnic groups
Culture Bias - Reliability
The same practitioner may diagnose 2 individuals with the same symptoms differently based on their cultural background
Culture Bias - Validity
Some individuals may be diagnosed incorrectly based on their cultural background rather than their symptoms
Culture Bias - Cochrane (1977)
Found that the incidence of sz in the West Indies and Britain is similar (~1%) but that people of Afro-Caribbean origin were 7x more likely to be diagnosed with sz when living in Britain. INVALID diagnoses of sz were made due to cultural bias due to ethnic stereotypes
Cultural Bias - Copeland et al. (1971)
Gave a description of the patient to 134 US & 194 British psychiatrists.
69% of US were diagnosed
BUT only 2% of British were diagnosed
Cultural Bias - Occurence
Escobar (2012) suggests that (overwhelmingly white) psychiatrists may tend to over-interpret symptoms and distrust the honesty of black people during diagnosis
Cultural Bias - other reasons
- Cochrane & Sashidharan (1995) argued racism and social deprivation immigrants tend to suffer more stress & therefore may influence the development of sz.
- Cochrane (1983) suggests the reason Afro-Caribbean people are the only immigrants to be more likely to be diagnosed with sz due to their little immunity to the flu
Gender Bias
The tendency to over/under diagnose sz in one gender/sex (men are more likely to be diagnosed
Gender Bias - Reliability
The same practitioner may diagnose 2 individuals with the same symptoms differently based on gender
Gender Bias - Validity
Some people may be diagnosed incorrectly based on their gender rather than symptoms
Gender Bias - Cotton et al. (2009)
Suggests that female patients tend to function/cope better than men, causing psychiatrists to make more diagnoses in men as their symptoms are more visual.
Gender Bias - other reason?
Men may be more genetically vulnerable to developing sz
Symptom Overlap
Where symptoms of sz are the same as the symptoms of other disorders/mental illnesses
Symptom Overlap - Reliability
Where different practitioners may diagnose the same individual with different disorders OR where the same practitioner diagnoses differently on different occasions
Symptom Overlap - Validity
Some individuals may be diagnosed incorrectly with the wrong disorder
Symptom Overlap - Ophoff et al. (2011)
Assessed genetic material from 50,000 pps and found 7 gene locations on the genome associated with sz. 3 were also associated with bipolar disorder, suggesting a genetic overlap.
Genetics
Sz may be (at least) partially inherited - contemporary views suggesting genetics explain at least 50% of the cause of sz.
-Unlikely there’s only one gene, polygenic!
Genetics - Twin Studies
As MZ twins share 100% of their genes & DZ twins share 50%, if sz was genetic, the concordance rate for MZ twins would be greater than for DZ twins
Genetics - Family Studies
Found that sz is more common among biological relatives of an individual with sz
Genetics - Family Studies: GOTTESMAN (1991)
Found CC rates of:
- Child w/ 2 sz parents was 46%
- Child w/ 1 sz parent was 13%
- Child w/ 1 sz sibling was 9%
- MZ twins 48%
- DZ twins 17%
Genetics - Adoption Studies
Similar to family studies but separates the effects of genes and environmental factors
Genetics - Candidate Genes
Gene-mapping has identified several candidate genes which may be associated with sz
Neural Correlates
The development of sz is related to structural/function brain abnormalities
Neural Correlates (-ve)
Avolition involves loss of motivation & the ventral stratum is linked with the anticipation of reward in motivation
Neural Correlates (+ve)
Lower activation levels in the superior temporal gyrus & anterior cingulate gyrus were found in individuals that have auditory hallucinations
Dopamine Hypothesis (original)
High levels/activity of dopamine in the subcortex was associated with the development of sz symptoms
Dopamine Hypothesis (evidence)
Post Mortems - sz showed hihg levels of dopamine
Amphetamine - increased dopamine activity results in symptoms similar to sz
Parkinson’s Disease - low dopamine levels are treated with amphetamines
Antipsychotic Drugs - drugs (like Chlorpromazine) block dopamine activity in the brain
Dopamine Hypothesis (new)
- Goldman-Rakic et al. (2004) -found a role of low dopamine levels in prefrotal cortex in -ve symptoms
- Davis et al. (1991) suggested that high levels of dopamine in mesolimbic dopamine system are linked with +ve symptoms & high levels in mesocortical dopamine system linked with -ve symptoms
Family Dysfunction
Where an individual develops sz because they were raised in a dysfunctional family environment
Family Dysfunction Characteristics
- High levels of interpersonal conflict
- Difficulties communicating with eachother
- Highly critical & controlling of children
Double Bind
Bateson (1956) - believed that faulty communication in families was a key risk factor in developing sz.
Parents place children in a no-win situation by giving them contradictory messages.
Expressed Emotion
Where the factors are high in a family, there’s a high level of stress for the patient and there are significantly more likely to replase
Expressed Emotion Factors
- Verbal Criticism fo the patient (which may occasionally include violence)
- Hostility towards the patient (including anger & rejection)
- Emotional Over-Involvement (including needless self-sacrifice)
Brown et al. (1966)
- Investigated the impact of family relationships on the recovery of sz patients, interviewing family members
- Found that the families with high levels of EE resulted in 58% of relapse compared to low EE families with only 10%
Cognitive Explanations
Sz is a result of cognitive deficits and/or dysfuncitonal processing
Beck & Rector (2005)
Proposed a model which combines many models:
- Neurobiological anomalies occur due to brain damage or genetic defect
- These abnormalities lead to an increased vulnerabilities to stress
- Leads to dysfunctional beliefs and behaviour
- Cognitive deficits occur in attention, communication & information processing
Frith et al. (1992)
Identified two kinds of dysfunctional thought processing that could underlie some symptoms:
- METAREPRESENTATION
- CENTRAL CONTROL
Metarepresentation
Ability to reflect on thoughts & behaviour, so dysfunction would disrupt ability to recognise own actions/thoughts, explaining auditory hallucinations
Central Control
Ability to suppress automatic responses, so disorganised speech/thoughts may be a result of an inability of this
Antipsychotic Drugs
Developed in 1950s to reduce the positive symptoms of psychosis
- either typical or atypical
Typical Antipsychotic Drugs
CHLORPROMAZINE (T/S/I)
- drugs that bind to dopamine receptors but don’t stimulate them, blocking receptors so dopamine cannot bind to them.
- initially causes a build up of dopamine levels in the synapse but overall production is decreased
- reduces frequency and strength of hallucinations etc.
Atypical Antipsychotic Drugs
CLOZOPINE (T/S)
- binds to dopamine receptors but don’t stimulate them, blocking receptors so dopamine cannot bind to them. (LIKE TYPICAL)
- but also blocks serotonin & glutamate receptors and is believed to improve mood & reduce depression and anxiety
RISPERIDONE (T/S/1)
- binds strongly to dopamine & serotonin receptors, but stronger than clozapine
Cognitive Behaviour Therapy (SZ)
Designed to help the sz patient change disorted & irrational thoughts into more accurate/rational ones.
- takes place over 5-20 sessions, usually individually for sz patients
Personal Therapy
A specific type of CBT that involves a detailed evaluation of problems and experiences.
TECHNIQUES:
- distractions
- challenging meanings from intruisive thoughts
- inc/dec social activity
-relaxation
CBT for Delusions
- Patients think about where delusions first started to gain a better understanding of its origin
- ARGUMENT with patient to encourage an evaluation of the content of their delusion
- Patient’s allowed to devleop alternatives like coping strategies
Family Therapy
Aims to increase tolerance, reduce critisism & guilt, and impreove communication in families of sz patients
- takes place over 9-12 months
LOWERING EE
Pharoah et al. (2010)
Identified a range of stratgies which family therapists aim to improve the functioniung of a family with a sz member:
- forming an alliance with all family members
- reducing stres of caring for a sz relative
- improve ability to solve problems with family
- reduction of anger & guilt
Token Economies
Uses principles of operant conditioning to help the MANAGEMENT of sz in institutions - POSITIVE REINFORCEMENT
Tokens
(coloured disks) - given out immediately to patients who have carried out desirable behaviours, individualised
- tokens can be exchanged for rewards, and are secondary reinforcers
Secondary Reinforcers
Indirectly reinforce behaviour by providing an access to a primary reinforcer (only have value once the patient has learm that they can be used to obtain rewards)
Primary Reinforcers
Directly reinforce behaviour & are biological (have direct value to the patient)
Rewards
Can be in the form of: materials, services, or privileges
Interactionism Explanation
Suggests sz develops through several interacting factors/explanations - DIATHESIS STRESS MODEL
Diathesis (DSM)
Vulnerability - a variety of different factors could cause vulnerability to sz
- genetics (Candidate Genes)
- psychological trauma (Read at al. (2001) early childhood trauma could significantly affect many aspects of brain development)
Stress (DSM)
Psychological triggers for sz can be high EE, substance abuse, critical life events etc. Those most at risk of developing the disorder will be most vulnerable to such triggers
Interactionist Treatments
The best form of treatment is to provide sz with a combination of different therapies, as research indicates that pairing multiple treatment leads to more effective results
