S11) Psychotic Disorders Flashcards
(56 cards)
What is psychosis?
- Psychosis is the presence of hallucinations or delusions
- It describes symptoms, not a diagnosis in itself
What are hallucinations?
- Hallucinations are a perception without a stimulus
- It can be in any sensory modality (visual hallucinations are organic e.g. tumour, eye disease) (auditory hallucinations were the commensest)
What are some hallucinations experienced in the ‘normal’ population?
- Hypnogogic – experienced when going to sleep (commonest, feeling like your name is called)
- Hypnopompic – experienced when waking up
usually auditory
What is a delusion?
A delusion is an abnormal fixed, false belief, outside of cultural norms (unshakeable- they truly believe it)
Identify five organic causes of psychosis
- Delirium caused by infection
- Hypercalcaemia
- Acute drug/alcohol intoxication
- Post-ictal psychosis
- Hyperthyroidism
Identify some iatrogenic causes of psychosis
- Steroids
- L-Dopas
Describe features of schizophrenia (myths to overcome)
Patients with schizophrenia don’t have a split mind or personality - it is a psychotic disorder!
Patients with schizophrenia are generally no more ‘dangerous’ than any other patient.
5% of violent crimes are committed by patients with severe mental illness, which means that 95% are committed by ‘normal people’!
Identify the first rank symptoms of schizophrenia (extremely diverse, manifesting in many diff ways)
- Auditory hallucinations
- Passivity experiences
- Thought withdrawal, broadcast or insertion
- Delusional perceptions
- Somatic hallucinations
Identify examples of auditory hallucinations?
– Thought echo – hearing thoughts aloud
– Running commentary –
‘He’s brushing his teeth, he’s sitting down’
– Third Person - Voices referring to patient in third person and conversing with each other about the patient
(voices they here are from the outside, not in their mind!)
What are passivity experiences?
Patient believes an action or feeling is caused by an external force
(felt like arm being moved by something else)
Distinguish between thought withdrawal, broadcast and insertion
- Thought withdrawal – thoughts are being taken out of the mind (feeling like someone else’s thoughts are in their head i.e. not your own thoughts)
- Thought broadcast – thoughts are being made known to others e.g. via radio
- Thought insertion – thoughts implanted by others
What is delusional perception?
‘attribution of new meaning, usually in the sense of self-reference, to a normally perceived object’
New meaning cannot be understood as arising from patient’s affective state or previous attitudes
The perception is real but then correlate it with something delusional
What are somatic hallucinations?
Mimics feeling from inside the body
– physical bodily sensations - e.g. a lady felt like a hamster was living insider her or e.g. the sense of being touched when noone is there.
Identify some positive symptoms of schizophrenia
Positive symptoms – added symptoms:
- Delusions
- Hallucinations
- Thought disorder (problem with organization of thoughts)
- Lack of insight
(ADDED SYMPTOMS)
Far better at treating positive symptoms than negative symptoms
Identify some negative symptoms of schizophrenia
Negative symptoms – symptoms that take away from the patient:
- Underactivity
- Low motivation
- Social withdrawal
- Emotional flattening
- Self neglect
(SYMPTOMS THAT TAKE AWAY FROM THE PT)
How can all patients with Schizophrenia be different?
– While patients with Schizophrenia might have the same cluster of symptoms e.g. delusions, hallucinations, absence of insight.
– How each patient experiences these symptoms will be completely different e.g.
- Delusions MI5 are following them
- Delusions witchcraft is being performed on them
- Delusions family are poisoning them
Describe the possible mechanisms for pathophysiology of Schizophrenia.
Dopamine pathways
Brain changes
Limbic system
Describe the dopamine theory of Schizophrenia.
– Drugs e.g. amphetamines which cause the release of DA induces psychotic symptoms.
– All medications that antagonise DA receptors (blocks D2 receptors) help treat psychosis & those with the strongest affinity to D2 receptions are most clinically effective.
– 4 DA pathways in the brain: mesocortical/ mesolimbic/ nigrostriatal (involved in Parkinson’s disease) / tuberoinfundibular pathways.
Describe the involvement of dopamine in schizophrenia?
– Drugs that increase dopamine levels (e.g.
amphetamines) induce psychosis
– Drugs that antagonise dopamine treat psychosis (especially those acting at D2 receptors)
Identify the 4 examples of dopaminergic pathways.
– Mesolimbic pathway
– Mesocortical pathway
– Nigrostriatal
– Tuberoinfundibular pathways.
Describe the role of the Mesolimbic pathway and Mesocortical pathway in Schizophrenia.
Mesolimbic pathway → thought to be overactive in schizophrenia (too much dopamine - mainly responsible for positive symptoms: hallucinations and delusions) - need to block dopamine in that pathway - use dopamine blockers
Mesocortical pathway → thought to be in underactive in schizophrenia (responsible for the most negative symptoms - harder to treat as the dopamine levels are much lower here, so when trying to combat the positive symptoms by using dopamine blockers, it enhances the negative symptoms)
Describe the mesolimbic pathway.
From Ventral tegmental area
To Limbic structures (amygdala, septal area, hippocampal formation) and Nucleus accumben
Describe the mesocortical pathway.
From Ventral tegmental area
To Frontal cortex and Cingulate cortex
Describe the common brain changes seen in Schizophrenia
Note: can’t do this scan to confirm the diagnosis though
– Enlarged ventricles
– Reduced grey matter (with reduced brain weight)
– Decreased temporal lobe volume
– Reduced hippocampal formation, amygdala, parahippocampal gyrus and prefrontal cortex
