An Introduction to Schizophrenia Flashcards
What does “Folie Circulaire” mean (Falvet, 1851)?
Cycling insanity
What term did Hecker coin in 1871, and what does it mean?
“hebephrenia”; a form of unusual and inappropriate youth.
Who combined the symptoms into a single disease?
Kraeplin (1878) was the first to describe Sz as a form of disease; “dementia Praecox”
In 1908, who defined schizophrenia as a split between affect and thought?
Bleuler
What did Schneider define in 1959?
First rank symptoms.
According to Kraeplin (1898), what is dementia praecox?
“Dementia” described the global disruption of perceptual and cognitive processes; “praecox” described the early adulthood onset. Kraeplin was the first to describe Sz as progressive, with no return to premorbid functioning.
What did Bleuler (1911) do?
He reformulated dementia praecox; coined the term Sz - “schizo” = split , “phrene” = mind. He characterised fragmented thinking as a breakdown of integrated functions that co-ordinate thought affect and behaviour.
Describe the positive vs negative dichotomy (Crow, 1980).
(Type I) Positive symptoms (symptoms which are present but shouldn’t be)
(Type II) Negative symptoms (symptoms which aren’t present, but should be)
What are positive symptoms of Sz?
Delusions, Hallucinations, Thought disorders
What are negative symptoms of Sz?
Anhedonia, flattened affect - limited range of emotions
Name some cognitive symptoms of Sz.
Avolition (lack of motivation), alogia (unable to speak), problems with working memory/planning/learning
What did Liddle (1987) do?
Re-examined the pos/neg dichotomy. Factor analytic study with 40 patients with chronic Sz. He confirmed the pos/neg dichotomy, but he also included a third factor called “disorganisation syndrome”, attributable to the positive dimension.
What syndrome categories did Liddle (1987, 2002) identify?
1) psychomotor poverty (poverty of speech/movement; blunted affect); 2) Reality distortion; 3) Disorganisation syndrome (inappropriate affect, thought disturbances). In 2002 Liddle added two more factors: 4) Psychomotor excitation; 5) Anxiety/depression
What did Fletcher & Frith (2009) do?
Gave examples of symptoms such as delusional perception, thought insertion. Just one symptom would be enough to diagnose a patient with Sz.
What did Weinberger find?
After MRI scans of discordant twins’ brains, a difference in ventricular size was found such that those with Sz have larger ventricles in the brain.
What is the percentage of concordance of developing Sz for identical twins?
48%
What did Ward find?
Lower activity in frontal cortex even when behaviour is comparable between patients and controls. Decreased brain activity in Sz subjects compared with normal controls in an fMRI study examining cognitive functioning.
What approaches are there to investigating the neurochemistry of Sz?
Post mortem studies; peripheral markers; mechanism of action of antipsychotic drugs - animal and human studies; in vivo receptor binding (PET)
Briefly, what is the dopamine hypothesis?
Sz results from overactivity in brain dopamine transmission. Hyperactivity in mesolimbic dopamine gives rise to positive symptoms, while hypoactivity in the frontal cortex results in negative symptoms.
What is the effects of neuroleptics?
Clinical potency of effective neuroleptics parallels their pharmacological potency in blocking dopamine binding. Parkinsonian side-effects of neuroleptics; amphetamine which releases dopamine induces psychosis that responds to neuroleptics.
What have receptor affinity studies found?
They have found increased D2 but not D1 receptors in the striatum.
What did Seeman (1993) find?
6 fold elevation of D4 receptors. Yet other studies have found no D4 receptors - even in controls.
What did Howes (2009) find?
Elevated striatal dopamine function linked to prodomal signs of Sz. There was a significant difference in Ki (influx rate constants) values at the group level for the whole striatum and for the associative striatum
What have metabolite measurements (peripheral markers) found?
Brain DA turnover can be reflected by plasma Homovanillic acid concentrations. Chronic antipsychotic treatment lowers plasma HVA which relates to good treatment outcomes.
