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
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