Psychosis Flashcards
What are the 6 pathologies of psychosis?
- Acute brain failure —> delirium
- Brain damage - encephalopathies
- brain injury
- strokes - Dementia - Alzheimer’s
- Vascular
- Parkinson’s
- Lewy Body
- Huntington’s - Personality disorder
- Mania depression - Schizoaffective disorder
- Puerperal psychosis (labour) - Secondary —> drugs, metabolic diseases, endocrine
diseases, infections
What is psychosis?
Failure to perceive and interpret reality
- Hallucinations and delusions (+thought disorder)
Why is psychosis difficult to diagnose and treat?
- Multiple causes
- represents a large group of different disease
processes —> collectively share end result
- represents a large group of different disease
- Patient doesn’t realise they are in psychosis
Which 2 factors impact an individual’s consciousness?
- Parallel processing of all senses (modular)
- Individual’s attention —> actively and passively
ignore certain stimuli
What are hallucinations?
When one’s own thoughts are experienced as external
Which 6 factors contribute to a patient developing hallucinations?
- Clinical disorders
- Negative emotional states
- Cognitive difficulties
- Coping with stress
- Family history
- Environment (eg. having childhood adversity)
What are delusions?
Fixed, false, unshakeable beliefs
- must be interpreted in social/cultural contexts
- brain trying to make sense of perplexity —> doxastic
shear-pin instead of full shut down
- often persecutory —> patient thinks they’re in
danger
What are the 9 symptoms of schizophrenia?
Positive (additional):
1. Hallucinations
2. Delusions
Negative (missing):
3. Anhedonia
4. Apathy
5. Social withdrawal
6. Blunted mood
Disorganised:
7. Thought disorder
8. Speech and behaviour
9. Inappropriate affect
What are the 2 core features of psychosis?
- Perplexity —> abnormal language
—> suspicious
—> abnormally important experiences - Lose mine-ness —> lose sense of self
How do genetics impact development of schizophrenia?
- Heritable - 80%
- 1 affected parent —> 10% risk
- 2 affected parents —> 50% risk
- affects monozygotic twin —> 40% risk - Epigenetics —> >200 genes (for neurodevelopment,
D2, inflammation)
What is the prevalence of schizophrenia
1%
What is the neurobiology behind schizophrenia? (2)
- Excess striatal dopamine - especially in response to
stress - Abnormal Default Mode Network (independent
thoughts and self-reflection)
Which scan can be used for schizophrenia diagnosis?
PET —> see excess striatal dopamine
Which neuropsychological processes are affected by schizophrenia?
Dopamine:
1. Anticipated reward
2. Reward prediction error signalling
3. Salience
Working Memory:
4. Though and perception context lost
What are the 5 causes of psychosis?
- Genetics
- Developmental adversity/abuse
- Impaired neurodevelopment (in utero issues)
- Life stressors
- Recreational drugs —> 25% psychosis
- cannabis
