Schizophrenia Flashcards
What percentage of the world population experiences schizophrenia?
About 1%
Schizophrenia is more commonly diagnosed in men, city-dwellers, and lower socioeconomic groups.
What are the two major systems for the classification of mental disorders?
- World Health Organisation’s International Classification of Disease (ICD-10)
- American Psychiatric Association’s Diagnostic and Statistical Manual edition 5 (DSM-5)
ICD-11 has been published but won’t be used for diagnosis until 2022.
What is the difference in diagnostic criteria for schizophrenia between DSM-5 and ICD-10?
DSM-5 requires at least one positive symptom, while ICD-10 requires two or more negative symptoms
Previous editions of ICD and DSM recognized subtypes of schizophrenia, which have since been dropped.
Define positive symptoms of schizophrenia.
Additional experiences beyond ordinary existence, including hallucinations and delusions.
What are hallucinations?
Unusual sensory experiences that can occur in any sense
Examples include hearing voices or seeing distorted images.
What are delusions?
Irrational beliefs, often involving persecution or having special powers.
Define negative symptoms of schizophrenia.
The loss of usual abilities and experiences, such as speech poverty and avolition.
What is speech poverty?
Reduction in the amount and quality of speech, characterized by delays in responses.
What is avolition?
Difficulty in beginning or sustaining goal-directed activities
Identified signs include poor hygiene, lack of persistence, and lack of energy.
What does reliability mean in the context of psychiatric diagnosis?
Consistency in diagnosis, both inter-rater and test-retest reliability.
What did Flávia Osório et al. (2019) report about the reliability of schizophrenia diagnosis using DSM-5?
Excellent reliability with inter-rater reliability of +.97 and test-retest reliability of +.92.
What is a limitation of the diagnosis of schizophrenia related to validity?
Criterion validity is low, suggesting schizophrenia might be over- or underdiagnosed.
What is co-morbidity in the context of schizophrenia?
The occurrence of schizophrenia alongside other conditions, such as depression or substance abuse.
What gender bias exists in the diagnosis of schizophrenia?
Men are diagnosed more commonly than women, possibly due to underdiagnosis of women.
What is culture bias in the diagnosis of schizophrenia?
Differences in symptom interpretation across cultures, leading to potential misdiagnosis.
What is symptom overlap in schizophrenia?
The presence of similar symptoms between schizophrenia and other conditions, such as bipolar disorder.
What is the relationship between genetic similarity and the risk of developing schizophrenia?
Risk of schizophrenia increases with genetic similarity:
* 2% for a relative like an aunt
* 9% for a sibling
* 48% for an identical twin
Based on findings from Gottesman’s family study (1991)
What are candidate genes in the context of schizophrenia?
Candidate genes refer to genes that are believed to be involved in the risk of developing schizophrenia, indicating that the disorder is polygenic.
Early research focused on identifying a single genetic variation, but later findings showed multiple genes contribute.
What significant finding did Ripke et al. (2014) discover regarding genetic variations and schizophrenia?
108 separate genetic variations were associated with slightly increased risk of schizophrenia in a study comparing 37,000 diagnosed individuals to 113,000 controls.
This highlights the complexity and heterogeneity of the genetic factors involved.
How can mutations in parental DNA contribute to schizophrenia?
Mutations can occur due to factors like radiation, poison, or viral infection, leading to schizophrenia even in individuals without a family history of the disorder.
Paternal age has been linked to increased risk of sperm mutation and schizophrenia.
What is the original dopamine hypothesis of schizophrenia?
The original hypothesis posits that high levels of dopamine (hyperdopaminergia) in subcortical areas of the brain contribute to schizophrenia symptoms.
This was based on the effects of antipsychotics reducing dopamine levels.
What did Kenneth Davis et al. (1992) propose regarding dopamine levels in schizophrenia?
Davis proposed the addition of cortical hypodopaminergia, which suggests low dopamine in the cortex contributes to negative symptoms of schizophrenia.
This updated hypothesis integrates both high and low dopamine levels in different brain regions.
What evidence supports the genetic explanation for schizophrenia?
Strong evidence from:
* Family studies showing increased risk with genetic similarity
* Adoption studies indicating biological children at risk despite adoptive environments
* Twin studies showing concordance rates of 33% for identical twins
This demonstrates a genetic vulnerability to the disorder.
What environmental factors are associated with an increased risk of schizophrenia?
Environmental factors include:
* Birth complications
* Smoking THC-rich cannabis during teenage years
* Childhood trauma
These factors interact with genetic predispositions, complicating the understanding of schizophrenia.
What is genetic counseling in the context of schizophrenia?
Genetic counseling provides risk estimates for couples with a family history of schizophrenia, informing them of the average likelihood of having a child who may develop the condition.
The estimates do not account for specific environmental influences on the child.
What evidence supports the role of dopamine in schizophrenia symptoms?
Evidence includes:
* Amphetamines increasing dopamine and worsening symptoms
* Antipsychotics reducing dopamine and alleviating symptoms
* Candidate genes affecting dopamine production or receptors
This suggests a strong link between dopamine and schizophrenia.
What limitation exists regarding the dopamine hypothesis?
Evidence for a central role of glutamate has emerged, showing raised levels in individuals with schizophrenia, indicating other neurotransmitters may also be involved.
Post-mortem studies and candidate genes linked to glutamate processing support this view.
What experiment did Catherine Tenn et al. (2003) conduct related to amphetamines?
Tenn induced schizophrenia-like symptoms in rats using amphetamines and relieved symptoms with drugs that reduce dopamine action.
This supports the dopamine hypothesis but also highlights the complexity of drug effects.
True or False: Amphetamine psychosis closely mimics schizophrenia according to Justin Garson (2017).
False
Garson challenged the idea that the symptoms induced by amphetamines accurately represent schizophrenia.
What is family dysfunction in the context of schizophrenia?
Family dysfunction refers to dysfunctional family dynamics that may contribute to the development of schizophrenia.
This includes issues like cold, rejecting, and controlling parenting.
Who proposed the concept of the schizophrenogenic mother?
Frieda Fromm-Reichmann proposed the concept of the schizophrenogenic mother in 1948.
She based this on accounts from her patients about their childhood experiences.
What characteristics define a schizophrenogenic mother?
A schizophrenogenic mother is characterized by:
* Coldness
* Rejection
* Controlling behavior
This parenting style creates a family climate of tension and secrecy.
What is the double-bind theory in relation to schizophrenia?
The double-bind theory posits that children in dysfunctional families receive mixed messages and feel trapped, leading to confusion and potential schizophrenia.
This theory emphasizes the role of communication style within the family.
What does expressed emotion (EE) refer to?
Expressed emotion (EE) is the level of negative emotion expressed towards a person with schizophrenia by their family members.
High levels of EE are linked to increased stress and relapse in schizophrenia.
List the components of expressed emotion.
The components of expressed emotion include:
* Verbal criticism
* Hostility
* Emotional overinvolvement
These elements contribute to stress for individuals with schizophrenia.
What is dysfunctional thinking in the context of schizophrenia?
Dysfunctional thinking refers to impaired cognitive processes associated with schizophrenia, affecting thought processing and contributing to symptoms.
This includes disruptions in normal thought processing.
What is metarepresentation dysfunction?
Meta-representation dysfunction is the inability to reflect on one’s own thoughts and behavior, leading to issues like hallucinations and delusions.
This cognitive ability allows insight into intentions and interpreting others’ actions.
What is central control dysfunction?
Central control dysfunction refers to difficulties in suppressing automatic responses while performing deliberate actions, which can lead to disorganized speech and thought patterns.
This can result in derailment of thoughts in individuals with schizophrenia.
What evidence supports the link between family dysfunction and schizophrenia?
Evidence includes:
* Insecure attachment in adults with schizophrenia
* High rates of childhood trauma among those diagnosed
Studies show a disproportionate likelihood of insecure attachment and abuse histories.
What is a limitation of family-based explanations for schizophrenia?
A limitation is the poor evidence base for traditional family theories like the schizophrenogenic mother and double-bind.
These theories lack systematic evidence despite clinical observations.
What is a potential negative consequence of research linking family dysfunction to schizophrenia?
Research can lead to parent-blaming, particularly of mothers, which adds stress to families already dealing with schizophrenia symptoms.
This raises ethical concerns about the impact of such research.
What did John Stiling et al. (2006) find in their research on cognitive tasks?
They found that individuals with schizophrenia took significantly longer to perform cognitive tasks, supporting the idea of impaired cognitive processes.
The tasks included the Stroop test, which measures cognitive control.
What is a proximal explanation in the context of cognitive theories of schizophrenia?
A proximal explanation focuses on immediate causes of symptoms, rather than underlying origins like genetics or childhood trauma.
Cognitive theories primarily address current cognitive dysfunction.
Is schizophrenia primarily a psychological or biological condition?
There is an ongoing debate whether schizophrenia is best viewed as a psychological or biological condition.
Some argue it has psychological roots while others point to genetic and developmental factors.
What are typical antipsychotics? What to dopamine antagonists do?
1st generation of drugs such as dopamine antagonists (Chlorpromazine)
They block dopamine receptors reducing dopamine action. Initially dopamine builds up, then production is reduced. Normalises neurotransmission which reduces hallucinations.
Also a sedative
What are Atypical antipsychotics?
Target a range of neurotransmitters e.g
Serotonin (Clozapine)
More effective than typical antipsychotics BUT potentially fatal as it can cause blood condition. Binds to dopamine, serotonin and glutamate receptors which improves mood, reduces depression and anxiety, and improves cognitive functioning
Thornley at al
Reviewed studies comparing effects of chlorpromazine to control conditions.
13 trials, 1121 pps showed it was associated w/ better functioning + reduced symptom severity.
MELTZER concluded clozapine was most effective in 30-50% of cases
Healy (2012)
Flaws of evidence for effectiveness. Most studies are short-term effects + successful trials published several times which exaggerates results. Antipsychotics have powerful calming effects, not the same as reducing psychosis
Side effects
Long-term use of typical antipsychotics can result in trade dyskinesia (involuntary facial movements)
Most serious effect-neuroleptic malignant syndrome (NMS): high temp, delirium, coma and can be fatal
How does cognitive behaviour therapy (CBT) help?
CBT helps client understand how irrational thoughts impact feelings and behaviour. Understanding where symptoms come from helps with symptoms like auditory hallucinations as it makes them less frightening and less debilitating. Teaches them to cope
How does family therapy help?
(What strategies + who developed them?)
Improves communication + interaction between family members
Pharoah- identified strategies to improve function of families
Reduces -ve emotions - reduce levels of expressed emotion to prevent stress that could result in relapse
Improves family ability to help -form therapeutic alliance (agree of therapy aims). Improve beliefs and behaviour about SZ, balance care and maintaining own lives
Evidence for effectiveness (Jauhar, Pontillo
-34 studies using CBT -> clear evidence for small but significant effects (research evidence)
-Reduced frequency + severity of auditory hallucinations (clinical)
Thomas (quality of evidence)
Diff studies use diff CBT techniques + ppl w/ diff symptom combinations
McFarlane
FT one of the most consistently effective.
Relapse rates reduced by 50-60%
FT promising when used in early stages
Lobban + Barrowclough
Benefits family (provide bulk of care) so strengthens function of whole family
