Schizophrenia (pack 2) Flashcards
What sort of disorder is schizophrenia?
A psychotic disorder
What is schizophrenia marked by?
remission, where they have no symptoms and relapse, where symptoms reoccur.
What are positive symptoms?
strange and bizarre additions to normal behaviour
What are negative symptoms?
loss or absence of normal symptoms
What are cognitive symptoms?
issues to do with information processing
What are the four positive symptoms for schizophrenia?
- Delusions
- Hallucinations
- disorganised thinking/speech
- Abnormal motor behaviour/grossly disorganised behaviour OR catatonia
What are delusions?
false or bizarre beliefs, even in the face of disconfirming evidence
What are some ways in which delusions are different in other cultures?
delusions tend to reflect predominant themes and values of a persons culture
e.g in Ireland a persons religious piety is greatly valued
what is disorganised thinking/speech?
there is an underlying problem with conscious thought that affects their language.
What are three negative symptoms?
lack of energy and motivation
social withdrawal
flatness of emotion
Why may negative symptoms be more objective?
negative symptoms are more directly observable
What are two cognitive symptoms in schizophrenia?
difficulties in concentration and paying attention
problems with working memory
What are the 3 features of schizophrenia?
Onset, prevalence and prognosis
when is typically the onset for schizophrenia
between the late teens and early thirties
When is peak onset for males and females?
early to mid twenties = M
late twenties = F
What does prevalence mean?
refers to how common a disorder is
What does prognosis mean?
The likely course of the disease
What are some general statistics for prognosis?
25% of people experience schizophrenic symptoms continually.
What is the average life expectancy for someone with schizophrenia?
10 years less than the overall population average
What is the dopamine hypothesis?
suggests that schizophrenia can be explained by changes of dopamine functioning in the brain
what are the three explanations within excess dopamine (hyperdopaminergia)
that explains positive symptoms in schizophrenia
- Low levels of an enzyme that breaks down dopamine (excess within synapses)
- presence of excess numbers of dopamine receptors at the synapses
- hypersensitivity of certain dopamine receptors
How does dopamine deficiency (hypodopaminerga) explain negative schizophrenia symptoms
low levels of dopamine in the mesocortical pathway
What are three strengths of the theory of neurotransmitters as an explanation for schizophrenia?
- Backed up by evidence from drug treatment: many antipsychotic medications used to treat schizophrenia by blocking dopamine
- People given drugs that treat Parkinson’s disease by increasing dopamine production, can experience schizophrenic symptoms, this provides testable evidence that excess dopamine plays a role
- the theory explains both positive and negative symptoms
What are three weaknesses of the theory of neurotransmitters as an explanation for schizophrenia?
- Not all patients with schizophrenia responded to these drugs. For example, Alpert and Friedhoff and found that some patients did not improve at all after taking dopamine antagonists
- the theory cannot prove that excess dopamine causes schizophrenia. Instead it may be a symptom
- Some anti-psychotic medications are effective, but focus more on serotonin than dopamine.
What should the chances of having schizophrenia be if someone is related to a schizophrenic if genetics are the correct explanation?
higher than 1%
what does Hilker suggest is the heritability rate for schizophrenia?
79%
How many genes does Wright say may be involved in causing schizophrenia?
up to 700
What are the two genes focused on for causing schizophrenia?
- the COMT gene
- the DISC1 gene
What is the link between the COMT gene and schizophrenia and what does the COMT gene do?
The COMT gene is deleted
The gene is involved in regulating dopamine levels
(if it is deleted, than high levels of dopamine remain)
What does the DISC-1 gene code for?
GABA
What does GABA regulate?
glutamate and dopamine
What are the three major types or research that have looked into the role of genetics?
- family studies
- twin studies
- adoption studies