Describe and explain Gottesman’s study
- large scale family study conducted
- found that the larger the genetic similarity, the higher the risk of developing Sz was - eg identical twins had 48% chance, and 2% if an aunt had it for example.
- positive correlation between genetic similarity and rate of Sz.
- supports the fact that the development of Sz may have something to do with genes.
Define candidate genes
a gene that is inherited, that makes one vulnerable to the illness
Which kind of genes are likely to be affected to contribute to Sz?
- the genes that code for neurotransmitters like dopamine.
Define aetiologically heterogenous
- means that diff combinations of genes are the cause of Sz in diff people.
What is the role of mutation in development of Schizophrenia?
name a supporting study.
- mutation caused by radiation, viral infection or poison and still be a genetic contribution to Sz.
- Brown et al shows evidence: positive correlation between paternal age and risk of Sz.
What is a neural correlate?
- the variations in neural structures that are corelated with higher risk of SZ
What was the original dopamine hypothesis?
- high levels of dopamine in cortical regions = Sz
What is the new dopamine hypothesis?
- both high and low levels of dopamine in different brain regions can be the contributor to Sz.
- early experience of stress seem to make some people more sensitive to cortical hypodopaminergic
What is a pro and con for genetic factors contributing to the development of Schizophrenia
Pro: Adoption studies show how that biological children were more at risk for development of Sz even if they grew up in an adoptive family
- shows that some people may be more vulnerable to developing Sz because of their genetic makeup.
Con: environmental factors are often not taken into account - and they often do contribute to Sz.
- eg: most people with Sz reported at least one childhood traumatic event, vs around only 1/3 reporting it in a a matched group.
- shows that genetic factors don’t provide a complete explaination to the biological explanations for Sz.
Give a pro and con for the evidence of the role of dopamine in SZ.
- pro: DA involved in SZ.
- amphetamines were shown to increase symptoms in people with SZ, whereas antipsychotics were shown to reduce DA, and the symptoms of SZ.
- shows that dopamine is involved in symptoms of SZ.
Con: possible that drugs that increase DA symptoms only MIMIC SZ not actually cause it. This means that it can be difficult to distinguish the them apart, and do not actually cause REAL SZenic symptoms.
How is Schizophrenia diagnosed?
- DSM-5 Symptoms: 1 positive symptom must be present
- ICD-10: 2 or more negative symptoms should be present.
Define positive symptoms and give and explain 2 examples
- they are symptoms that are additional experience beyond normal existence.
- hallucinations: SENSORY experiences, eg seeing or hearing things that other people don’t
- Delusions: irrational BELIEFS, eg them believing that they are a famous figure or have superpowers etc.
Define negative symptoms and give and explain 2 examples
- symptoms that are something that is absent from ordinary existence.
- speech poverty: involves diorganised patterns of speech - eg changing topic mid sentence, saying words that don’t make sense when put together etc.
- Avolition: when someone finds it difficult to keep up with a goal oriented activity, as their motivation + energy is low.
What is reliability?
- consistency in results - when multiple physicians reach the same diagnosis for the same individual or eg.
What is validity?
- is what we’re trying to assess actually being assesed.
- eg is the method appropriate for your question.
Name 3 (family) psychological explanations for SZ
- The schizophrenic mother
- Double bind theory
- Expressed emotion
Name 3 cognitive explanations for SZ
- Dysfunctional thinking
- Meta representation dysfunction. (ability to reflect on thoughts and behaviour.
- Central control dysfunction - inability to supress automatic thoughts and speech triggered by other thoughts.
Give pros and cons for family based psychological explanations for SZ.
+ can help develop treatments such as family therapy and reduce expressed emotion in families.
-: Very weak explanation - explainations for trauma, but not for mother specifically, making evidence empirical and sexist. (Mothers mostly blamed in this case)
-: socially sensitive to think that family causes Sz- adds on additional stress when families are already dealing with sz symptoms.
Name some pros and cons for cognitive explanations for SZ
Pros:
Stroop test evidence: people with Sz took almost twice as long to distinguish between word + colour.
—> shows that cognitive abilities are impacted with SZ.
Cons:
- not a focus on root cause of the conditions - focuses too much on the NOW and is reductionist in terms of involving genes etc. Shows that it only provides a partial explaination for sz.
Name types of biological therapy for sz, give examples of each
Typical antipsychotics eg chlorpromazine
Atypical antipsychotics eg clozapine/respridone
explain the mechanisms of typical antipsychotics.
- act as dopamine antagonists, so block dopamine receptors, helping reduce positive symptoms like hallucinations.
- also have a sedative effect - so are sometimes used to calm down patients.
Explain the mechanism of Atypical antipsychotics
acts on glutamate and serotonin in addition to dopamine.
State a difference in the mechanism of risperidone and clozapine.
- Risperidone binds more strongly to dopamine receptors, so is more effective at lower doses than clozapine.
Give pros of using antipsychotic drugs for sz.
Pros:
- can allow for engagement in CBT and other talk therapies, which can aid in faster treatment. Shows that antipsychotic drugs can act as a gateway to improve quality of life for people with sz.
- Allowed patients to be treated in their own community instead of in institutions, saving institutions money, and allowing patients to return to work.
