Schizophrenia Flashcards
Prevalence of Schizophrenia
→ affecting 0.7%
- Similar prevalence across cultures
- Equal gender distribution
Age of onset between 18-30
- Lifelong
- Earlier in men
Costs of Schizophrenia
- Score lower on every measure of quality of life
- Suicide rate is 10x general population
- Billions per year in financial costs
- 3% of prisoners
- 11% of homeless people have SZ
Schizophrenia Symptoms
- Positive symptoms: abnormal by their presence
- Negative symptoms: abnormal by their absence
Reality Distortion (Schizophrenia Psychotic Symptoms)
Hallucinations (false perceptions)
- Perception-like without an external stimulus
- Auditory are the most common, but visual, tactile, olfactory also
- Third-person hallucinations: patients hears voices discussing them and/or commenting on their actions
- Audible thoughts
- Command hallucinations
Delusions (false beliefs)
- Fixed beliefs not amenable to change in light of conflicting evidence
- Paranoid delusions: person believes that others are trying to harm them
- Grandiose delusions: person believes they have special powers or they are on a special mission
- Delusions of reference: words or actions of strangers have special relevance to them
- Delusions of control: experiences their actions being controlled by an outside force
- Thought insertion: person believes that thoughts are coming into their mind from an outside source
- Thought broadcast: person believes that thoughts are leaving their minds and entering the minds of others
Disorganisation Symptoms (Schizophrenia)
- Refers to disconnected or incomprehensible thought and speech, bizarre behaviour
Formal thought disorder
- Loose association
- Word salad
Inappropriate affect
Bizarre dress
Negative Symptoms (Schizophrenia)
- Represent deficits in normal behaviour and cognition
- Flat affect
- Alogia (poverty of speech)
- Avolition (poverty of will)
- Cognitive deterioration
Auditory Verbal Hallucinations Neurology
they activate identical brain regions to real voices
- There is nothing inherent in real sounds which enables them to be distinguished, ad hoc, from hallucinations
Basic History of Schizophrenia
- Hippocrates
- Kraeplin - dementia praecox
- Bleuler introduced the term, means ‘split mind’
Classical Models of Schizophrenia
Freudian
- SZ is a defence mechanism against latent homosexuality
Fromm-Reichmann
- Runs in families
Overbearing mother with SZ idea
Schizophrenia as a Brain Disorder
Grey matter abnormalities
- At baseline
- Progressive deficits over first few years
White matter abnormalities
Glial Cells
- Non-neuronal supporting cells of the brain
- Implanting human glial cells from individuals with SZ into mice led to the development of behaviours and traits associated with SZ
Occurs in late adolescence
- Grey matter volume reduces over adolescence (synaptic pruning)
- White matter volume increases over adolescence (myelination)
Risk Factors of Schizophrenia
- Identical twins have 48% chance of having SZ
- High genetic risk
- There is no single gene for SZ
Recreational drugs
- Amphetamine 10x risk
- It is a dopamine agonist
Gene-Environment Interactions: COMT Gene (SZ)
- Velocardio-facial syndrome (VCSF) occurs when there is a deletion of a piece of the long arm of chromosome 22
- High rates of SZ 25% in VCSF
- one of the deleted genes is COMT
- COMT is involved in breaking down dopamine
- Met/Met gene alongside cannabis at a young age has a much higher risk
Paranoid Delusions
person believes that others are trying to harm them
grandiose delusions
person believes they have special powers or they are on a special mission
delusions of reference
words or actions of strangers have special relevance to them
