Schizophrenia Flashcards
What are the 4 positive symptoms of SZ?
- Hallucinations
- Delusions
- Disorganised speech
- Catatonic behaviour
What are hallucinations?
Seeing/ hearing/ tactile (hearing). False perceptions.
What are delusions?
False cognitions and beliefs
What is disorganized speech?
Like word salad- saying random things that don’t make much sense
What is disorganized/catatonic behaviour?
Completion/motivation issues
What are the 4 negative symptoms?
- Avolition
- Speech poverty/ alogia
- Affective flattening
- Anhedonia
What is avolition?
Reduced motivation/ goal-directed behaviour where options are present. Hygiene, energy, sociability are all affected
What is alogia/speech poverty?
Loss of fluency/productivity- less speech in a given time
What is affective flattening?
A reduced range and intensity of emotions, even body language
What is anhedonia?
Loss of intrest/pleasure or reduced reactions that are pleasurable. The social aspect of this is confused with depression, but only physical anhedonia is reliable for SZ
What does the DSM-V classify as SZ?
2 or more symptoms for at least one month (one has to be positive) or episodes that add up to 1 month over 6 months
What age does SZ seem to develop?
Males- late teens or early 20s, females- around 4 or 5 years later
What is reliability in relation to SZ?
How consistently clinicians come to the same conclusions using the criteria (test-retest reliability) and agree with each-other (inter-rater reliability)
What is validity in relation to SZ?
How far the DSM measures what it says it does, and whether a diagnosis represents a clear, distinct ‘condition’
What was Rosenham’s case study; ‘being sane in insane places’? (1973)
- covert participant observation in 4 states in USA hospitals
- students reported hearing a ‘dull thud’ which is not an actual symptom
- they were all diagnosed with SZ and hospitalised. Given meds/treatment, not allowed to leave until the uni intervened
What were the findings of Rosenham’s case study?
- The inter-rater reliability was good but internal validity was very poor
- Rosenham later phoned the hospital and told them he would send more fake patients; in total, 21 percent of patients were then released as ‘pseudopatients’
- The inter-relater reliability was only 0.11 r which shows there was an inconsistent system that needed improvement
How is there a gender bias in the diagnosis of SZ?
BETA BIAS- in a study of 290 psychiatrists being asked to diagnose the same 2 patients. When they were told the patient was male, 56% diagnosed them with sz, when they were female only 20% were diagnosed (despite having identical symptoms). This shows problems with the reliability in diagnosis.
How is there cultural bias in the diagnosis of SZ?
- Overdiagnosis of SZ in west-indian psychiatric patients in Bristol- implies the symptoms of ethnic minority patients have been misinterpreted. Shows that you are more likely to be diagnosed if you’re from a BAME background- reliability issues
- Western culture dominates the diagnosing as in some ethnic cultures or religions, hearing voices is a sign from god/ spirituality is normal. Western values being placed upon non-western culture
What are the comorbidity issues with diagnosing SZ?
- An issue with depression, anxiety disorders, personality disorders
- Especially with depression/anhedonia (lack of pleasure)
- Symptoms overlap, an issue especially with disassosiative personality disorder
- Application issues- if you treat with drugs, the symptoms may get worse
Summed up, what is SZ thought to be caused by?
A combination of biology and psychological aspects. Genes, hormones, brain structure, cognitive styles, emotional factors. Diathesis stress model.
What do the dopamine receptor genes do? (D2, DRD2)
They affect the number of dopamine receptor sites and transport proteins for dopamine. This is an excitatory neurotransmitter.
What do glutamate receptor genes do? (AMPA)
They affect the number of glutamate receptor sites. Especially important in the basal ganglia. This is an excitatory neurotransmitter.
What was Gottesman’s family study about genetic factors?
He studied concordance rates in children with SZ parent(s) or siblings
2 SZ parents = 46%
1 SZ parent= 13%
1 SZ sibling = 9%
What was Joseph’s twin study about genetic factors?
Meta analysis of data on MZ vs DZ twin concordance for sz
MZ twins had 41% concordance
DZ twins had 7.4% concordance
Because MZ twins arent 100% concordant this highlights the impacts of the environment- link to nature vs nurture and diathesis stress
What was Tienari’s study about adoption and genetic factors?
He compared siblings that were raised together vs apart
- 164 adoptees had SZ mothers- of these, 6.7% also developed SZ
- 197 adoptees in a control group. 2% of them developed SZ
The conclusion from this was that there was a confirmed genetic liability
What is the dopamine hypothesis?
This states that SZ is caused by imbalances of dopamine
They either:
- have too many D2 receptors
- D2 receptors are too sensitive or fire too often
- They produce too much dopamine
What are dopamine’s actions in the brain known as?
Dopaminergia
What is hyperdopaminergia?
An excessive amount of dopamine
What is hypodopaminergia?
Too little/less than normal dopamine
What is hyperdopaminergia associated with?
in the subcortex, POSITIVE symptoms
Broca’s area produces speech; too much dopamine here leads to the speech and hearing related symptoms
What is hypodopaminergia associated with?
In the cortex is associated with NEGATIVE symptoms
PFC is the central executive in cognitive processes/decisions. Too little leads to avolition or catatonia
Evidence that supports the dopamine hypothesis?
Drugs that increase dopaminergic activity:
- amphetamines
- L-dopa (Grilly, 2002)
Drugs that decrease dopaminergic activity (antipsychotics):
- Chlorapromazine (act on dopamine)
- Clozapine (act on dopamine and seratonin)
What is a study with amphetamines that support the dopamine hypothesis?
Normal/un-schizophrenics who are exposed to large doses of dopamine releasing drugs like amphetamines can develop the characteristic hallucinations and delusions of a sz episode, which disappear when the drug is no longer taken
What would too much dopamine in the mesolimbic pathway lead to?
Developing positive symptoms
What would too little dopamine in the prefrontal cortex lead to?
Developing negative symptoms
What is some evidence supporting the impacts of abnormal brain structure on SZ?
The size of the ventricles/hollow areas in the brains of SZ patients compared with the brains of people without it. People with SZ had enlarged ventricles; suggesting SZ is linked to a reduction in the temporal and frontal lobe volume. MRI scans support this idea.
What is some evidence against the impacts of abnormal brain structure on SZ?
- People with SZ can also have enlarged ventricles, showing the relationship isn’t always simple
- The evidence shows a correlation but not a causal relationship; perhaps enlarged ventricles is just a symptom of SZ?
What is an animal study that supports the impacts of hypodopaminergia?
Induced dopamine depletion in the prefrontal cortex in rats which resulted in - symptoms (cognitive impairments including memory). Researchers were able to reverse this using an atypical antipsychotic drug.
What is comorbidity in SZ?
Symptoms may overlap with others- which disorder came first and which one Is the main cause of illness?
SZ and depression often found together