schitofrenie Flashcards
What is schizophrenia?
Mental health condition
Psychotic illness
Long-term illness
What are the positive symptoms?
Disorganised speech/behaviour
- catatonia (non-responsiveness to external stimuli)
- looseness of association
Hallucinations
Delusions
- paranoia
What are the negative symptoms of Sz?
Lack of initiative and persistence/motivation (avolition)
Poverty of speech (alogia)
Anhedonia - reduced ability to experience pleasure
Social withdrawal
Flattened emotional response
What is the diagnostic criteria in DSM-5?
At least 2 symptoms for a significant portion of time during 1 month
-delusions
-hallucinations
-disorganised speech
-grossly disorganised or catatonic behaviour
-negative symptoms
At least 1 of these symptoms:
-delusions
-hallucinations
-disorganised speech
Must be ongoing for 6 months
Can’t be attributed to another condition
Sz has to produce dysfunction in their life
What are the genetic factors for Sz?
Sz is a hereditary disorder
Rates are higher in families than in general population
What are the genes linked to Sz?
Neurodevelopment (abnormalities in developing brain)
Dopamine regulation
Prefrontal cortex (executive functioning and emotion processing)
What genes are responsible?
No single gene confers susceptibility to Sz
Multiple genes are responsible
There is interplay between genes and environment: epigenetic factors (the environment affects gene expression)
What are the neural correlates?
Larger ventricles (spaces in brain filled with cerebrospinal fluid)
Due to atrophy (loss of brain tissue)
What is atrophy?
Atrophy is loss or deterioration of neurones in
- cerebral cortex (attention, language, thought)
- limbic brain regions (emotion)
What is the dopamine hypothesis?
Drugs act to reduce the amount of dopamine in the brain.
Acts by blocking dopamine receptors.
Theory that Sz is due to too much dopamine.
What is the update dopamine hypothesis?
Sz is related to an overactive dopamine system.
Not too much dopamine, but differences in the way receptors signal to increase or reduce dopamine.
Other neurotransmitters are involved i.e. glutamate
Other receptors are also involved i.e. GABA
What are environmental factors that affect Sz?
Prenatal factors
Urban environment
Stress
Cannabis use
How can prenatal factors cause Sz?
Prenatal infections:
Influenza
Poliomyelitis
Respiratory infection
Rubella
How can stress cause Sz?
Stress has an impact on brain
Particularly in sensitive hippocampal region
Stress leads to reductions in hippocampal volume
What are the treatments for Sz?
Anti-psychotic medication
CBT
