Schizophrenia Part 1 Flashcards
How long does the prodromal period last?
Fe days to 18 months
What are the obvious effects on functioning?
Memory and concentration problems Unusual behaviour and ideas Disturbed communication and affect Social withdrawal Apathy and reduced interest
What follows an acute episode?
Hallucinations, delusions, behavioural disturbances, with agitation and stress
What are the positive symptoms (acute)?
Thought insertion
3rd person auditory hallucinations
Thought disorder (not making sense), broadcasting (thinking that people can hear what are thinking) and blocking (stopping mid sentence)
Delusional perception
What is the duration criterion for diagnosis?
The positive symptoms persisting for one month
What are the negative symptoms (chronic)?
Flatterned mood Indifference Social isolation Poor self care Poverty of speech
What are other characteristic symptoms?
Cognitive impairment
Working memory
Semantic memory (long term and processing, common knowledge)
What are confirming criteria for a diagnosis?
Positive or negative or both symptoms for 1 month
significant impact on work and daily tasks
Exclusion of recreational drug use or bipolar
What pathways are there in the brain and which of these are affected in psychosis? (see diagram)
1) Nigrostriatal pathway: substantia nigra and dopamine release
2) Mesocortical and mesolimbic pathway: nucleus accumbens. **
3) Tuberoinfundibular pathway: prolactin release
What is the role of dopamine in schizophrenia and evidence?
Excess dopamine and receptors
In CSF, there are abnormal levels of dopamine, receptors and its metabolites
D2 antagonists are effective in symptom management, and agonists cause psychosis
What other pathways are effected?
- Signally via the NMDA receptor is implicated; NMDA receptor antagonists like ketamine produce symptoms
What does brain imaging show?
- Abnormalities in cerebral blood flow and metabolism; impairment of neuronal circuits
- Impairment in frontal cortex, hippocampus, thalamus and cerebellum
What are the structural brain changes?
Enlargment of lateral ventrciles
Decrease in size
Affected white matter and no gliosis, no neurodegeneative process
What is the genectic cause?
Increased risk with family history
Neruregulin and Dysbindin genes influence neurodevelopment and synaptic functioning, leading to schizophrenia
What are the environment causes?
Males Cold weather countries Early cannabis use Germ cell mutations, older father Malnutrition and altered brain development in early life
