Schizophrenia Flashcards
Define Sz
Disorder characterised by distored thinking, impaired emotional responses, poor interpersonal skills and distortion of reality.
Define classification
List of symptoms
ICD-10, Where’s it used, Sz classification
Mainly used in UK.
2 or more negative symptoms, for one month or longer
DSM-5, Where’s it used, Sz classification
Mainly used in US.
1 positive symptom present for at least 1 month
Whys ICD-10 better than DSM-5
ICD-10 recognises subtypes of Sz, e.g. Catatonic Sz, which involves severe loss in movement
Whats the difference between negative and positive symptoms?
Negative symptoms are a loss of usual abilities and experiences, while positive symptoms are additional experiences beyond those of everyday existence.
Negative symptoms of Sz
Avolition: Severe loss of motivation to carry out normal tasks, and difficulty to begin or keep up with goal-directed activity. Anderson identified 3 signs of avolition: Poor hygiene, lack of persistence in work/school, lack of energy
Speech poverty: Reduction in amount and quality of spoken language, sometimes accompanied by a delay in verbal responses in a conversation. Involves derailment; where a person continues to say first thing that comes to their mind, resulting in constant change in topic of conversation
Positive symptoms of Sz
Hallucinations: Unusual sensory experiences that have no basis in reality. Includes auditory(Hearing things that aren’t present) and visual(Seeing things that aren’t present)
Delusions: Irrational/false beliefs that have no basis in reality. Can make people behave in ways that make sense to them but bizarre to others. e.g. delusions of control; beliefs that someone else is controlling the individual such as aliens
Define diagnosis
Labelling an individual with a mental illness
Whats a study done to check reliability of diagnoses
Cheniaux:
- Asked 2 psychiatrists to diagnose 100 patients using DSM-5 and ICD-10
- 1st: DSM-5: 26, ICD-10: 44
- 2nd: DSM-5 13, ICD-10: 24
- Low inter-rater reliability and inconsistent
-> Discuss: NHS funding
How does symptom overlap affect reliability and validity of Sz classification and diagnosis
- When 2 or more conditions share the same symptoms e.g. sz and depression both involve negative symptoms such as avolition.
- Can lead to misdiagnoses of illnesses
-> Discuss: Waste of taxpayers’ money in NHS
How does co-morbidity affect reliability and validity of Sz classification and diagnosis
- When an individual suffers from two illnesses/conditions at the same time e.g. People commonly diagnosed with Sz and one other illness
- Buckley et al.: 50% of patients with Sz also have depression and 23% have OCD
- Psychiatrists may not be consistent in diagnosing people with more than one illness and some may not correctly diagnose the illness
How does Gender bias affect reliability and validity of Sz classification and diagnosis
- Since 1980s, men diagnosed more frequently than women.
- Could be because men are more genetically vulnerable to Sz, in comparison to women.
- Alternative explanation could be because females are better at masking symptoms because they function better than men e.g. working and maintaining good family connections
How does culture bias affect reliability and validity of Sz classification and diagnosis
- English people of African origin are more likely to be diagnosed with Sz in the UK(Can’t be due to genetic vulnerability as cases are low in areas of Africa and West Indies).
- Higher rates may be due to some behaviours classed as positive symptoms in the UK e.g. Auditory hallucinations, may be classed as normal in African cultures
Genetic Explanation of Sz
- Passed through generations - Hereditary
- Born with genetic predisposition to Sz
- Several maladaptive genes such as PCM-1, increase individual’s chance of developing Sz. - Polygenic
- Gottesman’s twin study: MZ: 48% concordance , DZ: 17% concordance
- The closer the genetic link, the higher the chance of developing Sz
-> Counter: Not 100%, so must have other factors influencing acquisition of Sz
AO3 on genetics as an explanation of Sz
Tierney’s research to support:
- 155 adopted children with biological schizophrenic mother.
- Adopted kids had a 10% concordance rate, compare to 1% in adopted children without a schizophrenic biological mother.
- Supports role of genetics as Social learning theory couldn’t take place, so must be an inherited internal factor such as genetics
Neural correlates as an explanation of Sz
- Idea that brain structure links with symptoms of Sz
- Use fMRI scans
- Neuroanatomy: Raz and Raz: Meta-analysis that found over half of individuals tested with Sz had enlarged ventricles compared to a control group. This is associated with damage to the central brain area and pre-frontal cortex(involved in reward anticipation) - so involved in negative symptoms of Sz such as avolition
AO3 on neural correlates
Research to support: Suddath et al.: MRI scans used to see brain structure in MZ twins, in which one has Sz. Twin with Sz had more enlarged ventricles, which suggests they play a role in sz.
Dopamine hypothesis as an explanation for Sz
- Neurotransmitters appear to work differently in the brain of those with Sz.
- Individuals with Sz may release too much dopamine or have too many D2 receptors on the post synaptic neuron.
- Hyperdopaminergia in subcortex: High dopamine activity in Broca’s area may be associated with auditory hallucinations
- Hypodopaminergia in cortex: Low dopamine activity in prefrontal cortex(thinking and decision making), associated with negative symptoms of Sz such as avolition.
- Both could be the correct explanation but depend on the symptoms that are experienced
AO3 on dopamine hypothesis
Application to real-life: Drug therapies such as antipsychotics, which decrease levels of dopamine in the brain by blocking receptors - dopamine receptor antagonists. Bio explanation for Sz has a place in society due to it’s practical applications in treatment of Sz.
What are the 3 parts of family dysfunction as an explanation for Sz
Schizophrenogenic mother, Double-bind communication and high expressed emotion
Schizophrenogenic mother as a family dysfunction
1) Mother is cold, controlling, rejecting, emotionally unresponsive in early infancy. Family climate is tense and secretive. Father is passive
2) Child feels high level of distrust
3) Leads to symptoms like paranoid delusions
Double-bind communication as a family dysfunction
1) Bateson et al. identified faulty communication patterns within families. The verbal message does not match non-verbal communication
2) Child feels Anxious(withdrawing/avoiding social contact), Contradictory message(confusion)
3) Withdrawal results in avolition, Confusion results in paranoid delusions
High expressed emotion as a relapse explanation
1) Family shows verbal critisism, occasional violence, show hostility, emotional over-involvement.
2) Patient faces stress
3) Increases risk of relapse of Sz
