Schizophrenia Flashcards
Schizophrenia
- Disorder of thought, split from reality.
- Heterogenous.
- Many symptoms
- Not a split personality disorder
Describe the prevalence of schizophrenia and who is most affected
- Under 1% of population
- Late teens or early adulthood
- Earlier in men than women
- Women have better long term outcomes and less severe symptoms.
Describe the history of Schizophrenia
- Krapelin was the first to classify as dementia praeco in 1898. Viewed it as an early onset form of dementia which had a progressive intellectual deterioration. Not a decline in all.
- Bleuler renamed the disorder in 1908 to dissociate it from dementia. Characterised by disorganisation of thought processes, split from reality.
What are the three clusters of symptoms in Schizophrenia?
Positive
Negative
Disorganised
Positive Symptoms
Excesses and distortions of perception and thought. Something added to experience e.g. delusions and hallucinations
Delusions
- Beliefs held contrary to reality and firmly held in spite of disconfirming evidence
- Paranoid in nature - Feel like being spied on.
Thought insertion
- Form of delusion
- Believe thoughts belong to someone else
- Placed by external source
Thought broadcasting
- Form of delusion
- Believe others can read thoughts
Grandiose Delusions
- Exaggerated sense of own importance
- Believe have power over others
How do those with schizophrenia have abnormal perceptions
De-realization - World has changed and no longer feels real.
Have heightened perception. Busy spaces are overwhelming.
Describe the hallucinations experienced by those with schizophrenia
- They are sensory experiences. Auditory most common.
- 75% report hearing voices
- Voices telling them things, threatening to do things, violence.
- Allen et al. (2004) - Those with these likely to misattribute recordings of their own speech to a different source.
Negative Symptoms (Schizophrenia)
- Deficit e.g. in motivation, mood
- Usually in chronic cases
- Strong predictor that may not respond well to treatment
- Poor quality of life
Provide examples of negative symptoms (schizophrenia)
Avolition: Lack of motivation and absence in interest
Asociality: Social withdrawal
Anhedonia: Inability to experience pleasure. Deficit in anticipatory pleasure, don’t see hope in future activities.
Blunted Affect: Lack of outward expression of emotion (66%)
Alogia: Reduction in amount of speech
Disorganized Symptoms (Schizophrenia)
- Fragmentation of cognitive function
- Problem maintaining thought and speech, attention.
Loose Associations - Able to communicate, but can’t stick to one topic
Catatonia: Abnormality of movement. Overactivity e.g. gesture repeatedly or may not move for hours. Seen less now.
Identify the symptoms of schizophrenia as described in DSM-5
- Delusions
- Hallucinations
- Disorganised speech
- Disorganized behaviour
- Negative symptoms
- Impair life, work etc.
- Has to be present for longer than 6m.
State some of the differential diagnoses from schizophrenia and how they differ
Schizoaffective Disorder - Mixture of schizophrenia symptoms and mood disorders.
Schizophreniform Disorder - Schizophrenic lasting 1-6m
Brief Psychotic Disorder - 1 day to 1 month. Brief
Delusional Disorder - Delusions in absence of other schizophrenia symptoms. Less bizarre e.g. think have disease
Substance Abuse: Alcohol, meth
Medical: Tumours, fever
Explain the genetic risk factors associated with schizophrenia
- Negative symptoms have stronger genetic component
- DZ Twins: 12%
- MZ Twins: 44.30%
- Gottesman et al. (2010) - 2million ppl, Denmark. Higher rates of it in those with 2 parents who have it (27.3%)
- No single gene predicts it.
- Some suggestion that genes can predict other disorders, but difficult to find one specific.
Explain the dopamine hypothesis in regards to schizophrenia
- Suggest its due to excess activity of dopamine.
- Parkinson’s - Treatment incs dopamine, patients show psychotic symptoms like schizophrenia. Evidence that due to overreation of dopamine.
- Effective drugs reduce dopamine activity
- Excess numb of dopamine receptors or oversensitive dopamine receptors
- Not complete - medications take weeks to show effects. Physiological instant. Why is this?
Explain the role of serotonin in regards to schizophrenia
- Newer anti-psychotic medications more effective than old as they block the serotonin receptor 5HT2.
- Regulates dopamine transmission in the mesolimbic pathway.
Explain the role of GABA in schizophrenia
- Inhibitory function
- Deficits led to inhibition problems
- Said to be disrupted in the prefrontal cortex of those with schizophrenia
Explain the role of glutamate in schizophrenia
- Low levels found in the cerebrospinal fluid of those with disorder
- Low levels of enzyme needed to produce glutamate
- NDMA part of glutamate system
How are the ventricles impacted in schizophrenia?
- Are fluid filled sacs with cerebral spinal fluid
- Size increases over course of illness, making brain matter decrease
- Impaired perf on neuropsychological tests
How is the prefrontal cortex impacted in schizophrenia?
- Role in speech, decision-making, emotion which are all disrputed in schiz.
- MRI show reduction in gray mater.
- Fewer dendritic spines - Communication among neurons disrupted
- Reduced metabolic activity which place demands on area
How is the temporal cortex impacted in schizophrenia?
- Reduced volume of hippocampus - Memory deficits and brain areas associated with language processing
- Abnormal amygdala activity - Heightened activity of emotion processing, hallucinations?
