12.2 psychosis Flashcards
what are the symptoms of psychosis?
hallucinations or delusions
what are hallucinations?
perception without a stimulus
can be in any sensory modality
in normal population
Hypnogogic = going to sleep hallucinations
hypnopompic = waking up hallucinations
what are delusions?
abnormal belief outside of cultural norms, unshakeable
what can cause organic psychosis?
organic = abnormal brain function due to known psychical disability
causes
- infection
- drugs/alcohol
- hyperthyroidism
- encephalitis
- hypercalcaemia
- cerebral lupus
what are the first rank symptoms for schizophrenia?
- auditory hallucinations e.g hearing thoughts out loud, running commentaries etc.
- passivity experiences e.g their actions are being caused by an external force
- thought withdrawal, broadcast or insertion = thoughts being taken out of mind/ being broadcasts/ thoughts being put by others in their mind
- delusion perceptions e.g giving a meaning to a normal object
- somatic hallucinations e.g mimics feelings from inside the body
ALSO LACK OF INSIGHT, WON’T BELIEVE THEY ARE UNWELL
what symptoms add (be positive) and take away (be negative) from the patient?
add ( positive symptoms)
- delusions
- hallucinations
- thought disorder
- lack of insight
take away ( negative symptoms )
- underactivity
- low motivation
- social withdrawal
- emotional flattening
- self neglect
what is the ICD10 diagnosis for schizophrenia?
one of the following
- thought echo/insertion/withdrawal/broadcast
- delusions
- hallucinations of voices
or at least 2 of
- hallucinations
- neologisms
- catatonic behaviour
- negative symptoms
what are the types of schizophrenia?
Paranoid
- delusions or hallucinations prominent
Hebephrenic schizophrenia
- inappropriate behaviour, aimless and disjointed
- speech affected
- hallucinations/ delusions dont dominate
simple
- loss of drive and interest, social withdrawal
- marked decline in social/academic/work performance
undifferentiated
- many symptoms = fit more than one criteria
catatonic
what is the mesolimbic pathway and how is it affected in schizophrenia?
Mesolimbic pathway
From - ventral tegmental area
To - limbic structures (amygdala, septal area, hippocampus) and Nucleus accumbens
a dopamine pathway
thought to be overactive in schizophrenia
what is the mesocortical pathway and how is it affected in schizophrenia?
mesocortical pathway
from - ventral tegmental area
to - frontal cortex and cingulate cortex
thought to be under active in schizophrenia (so get -itive symptoms)
how does brain formation change in schizophrenia?
enlarged ventricles
reduced hippocampal formation, amygdala, parahippocampal gyrus and prefrontal cortex
what the principle used to treat schizophrenia?
typical antipsychotic
- Block D2 receptors in all CNS dopaminergic pathways
- maintain action as antipsychotics is on mesolimbic and mesocortical pathway
usually the drugs
- have low affinity D2 receptors
- mild side effects as dissociate rapidly from D2 receptor
what can be the ADR of antipsychotic drugs?
can cause Parkinson’s symptoms
e. g
- bradykinesia
- tremor
- muscle rigidity
as it lowers dopamine in the brain
what is the nigrostriatal pathway?
from substantia nigra pars compacta
to striatum (caudate nucleus and putamen)
(summary = less dopamine = less movement)
why would a schizophrenic patient develop catatonia?
if untreated can get catatonia, includes one or more of - mutism - excitement - posturing - negativism - rigidity - waxy flexibility - command automatism
