Schizophrenia Flashcards
(20 cards)
what is the neurodevelopmental hypothesis?
people who experienced hypoxic brain injury at birth or were exposed to infetions in utero are at greater risk of developing schizophrenia
other examples
- temporal lobe epilepsy
- those who smoke cannabis
how does neurodevelopmental damage present?
enlarged ventricles, small amounts of grey matter and smaller, lighter brains
what is the NT hypothesis?
an excess of dopamine and overactivity in the mesocorticolimbic system is believed to cause the positive symptoms of schizophrenia
less dopamine activity in mesocortical tracts, which cause the negative symptoms in schizophrenia
why do people with Parkinson’s experience psychotic symptoms in relevance to levodopa medication?
if they are overtreated w levodopa it increases the amount of dopamine in the brain
what substancs can increase dopamine release and lead to psychosis?
amphetamines
cocaine
cannabis
novel psychoactive substances - ivory wave, spices
LSD
other than dopamine what other NT’s are implicated in schizophrenia?
there is an increase in:
- serotonin activity
- glutamate activity
what are the subtypes of schizophrenia
- paranoid schizophrenia
- hebephrenic schizophrenia
- catatonic schizophrenia
- undifferentiated schizophrenia
- residual schizophrenia
- simple schizophrenia
what is paranoid schizophrenia?
most common type and is characterised by:
- paranoid delusions
- auditory hallucinations
what is hebephrenic schizophrenia?
usually diagnosed in adolescents and young adults and is characterised by:
- mood changes
- unpredictable behaviour
- shallow affect
- fragmentary hallucinations
outlook is often poor as negative symptoms may develop rapidly
simple schizophrenia?
similar to hebephrenic schizophrenia - characterised by negative symptoms:
- however in simple, patients have NEVER experienced positive symptoms
catatonic schizophrenia?
characterised by:
- psychomotor features e.g. posturing, rigidity and stupor
undifferentiated schizophrenia?
patients are designated as having undifferentiated schizophrenia when their symptoms do not fit neatly into one of the other categories of schizophrenia
residual schizophrenia?
characterised again by negative symptoms:
- occurs when positive symptoms have burnt out
are patients more likely to develop schizophrenia is there is a family history of it?
yes
- 50% monozygotic twin
- 15% if they are a dizygotic twin
- also if there father is aged over 55 when the child is conceived
what are the risk factors during pregnancy?
- malnutrition
- viral infections
- other complications e.g. pre-eclampsia, emergency caesarean section also increase risk
what is the neurodevelopmental hypothesis?
people who experienced hypoxic brain injury at birth or were exposed to infections in utero are at greater risk of developing schizophrenia
other examples
- temporal lobe epilepsy
- those who smoke cannabis
which ethnicity is most at risk?
- afro-caribbean men
clinical features are divided up into positive and negative symptoms - positive - change in behaviour or thought, whilst negative - decline in normal functioning… name some of these symptoms?
positive symptoms
- thought echo
- thought insertion or withdrawal
- thought broadcasting
- 3rd person auditory hallucinations
- delusional perception
- passivity and somatic passivity
- odd behaviour
- thought disorder
- lack of insight
negative symptoms
- blunted affect
- apathy
- social isolation
- poverty of speech
- poor self-care
what are the investigation into schizophrenia?
- if a patient is suspected to have schiz they will be referred to local community mental health team - psychiatrist or specialist nurse carries out a detailed assessment
- lab IX - baseline blood tests, urine culture - rule out UTI causing delirium, urine drug screen, HIV testing, syphilis serology, serum lipids
- CT head - if organic neurological cause is suspected
according to ICD-10 what does a dx of schizophrenia require:
first rank symptom or persistent delusion present for at least one month:
- delusional perception
- passivity
- delusions of thought interference - thought insertion, thought withdrawal and or/thought broadcasting
- auditory hallucinations - thought echo, third person voies, and or/running commentary
no other cause for psychosis - e.g. drug intoxication or withdrawal, brain disease (demetia/delirium/epilepsy) or extensive depressive or manic symptoms - unless its clear that schizophrenic symptoms antedate the affective disturbance
