S12) Psychotic Disorders Flashcards
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)
What are some hallucinations experienced in the ‘normal’ population?
- Hypnogogic – going to sleep
- Hypnopompic – waking up
What is a delusion?
A delusion is an abnormal belief, outside of cultural norms (unshakeable)
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
Identify the first rank symptoms of schizophrenia
- Auditory hallucinations
- Passivity experiences
- Thought withdrawal, broadcast or insertion
- Delusional perceptions
- Somatic hallucinations
Distinguish between thought withdrawal, broadcast and insertion
- Thought withdrawal – thoughts are being taken out of the mind
- Thought broadcast – thoughts are being made known to others e.g. via radio
- Thought insertion – thoughts implanted by others
Identify some positive symptoms of schizophrenia
Positive symptoms – added symptoms:
- Delusions
- Hallucinations
- Thought disorder
- Lack of insight
Identify some negative symptoms of schizophrenia
Negative symptoms – symptoms that take away from the patient:
- Underactivity
- Low motivation
- Social withdrawal
- Emotional flattening
- Self neglect
In the ICD10 diagnosis of schizophrenia, a patient with schizophrenia must present with at least one of which symptoms?
A) Thought echo, insertion, withdrawal, broadcast
B) Delusions of control, influence or passivity
C) Hallucinatory voices
D) Persistent delusions that are culturally inappropriate and completely impossible
In the ICD10 diagnosis of schizophrenia, a patient with schizophrenia must present with at least two of which symptoms?
E) Persistent hallucinations in any modality, occurring every day for at least one month
F) Neologisms, breaks or interpolations in the train of thought, resulting in incoherent/irrelevant speech
G) Catatonic behaviour
H) Negative symptoms e.g. marked apathy, paucity of speech, incongruity of emotional responses
Identify the different types of schizophrenia
- Paranoid schizophrenia
- Simple schizophrenia
- Hebephrenic schizophrenia
- Undifferentiated schizophrenia
- Catatonic schizophrenia
What is paranoid schizophrenia?
Paranoid schizophrenia – delusions or hallucinations prominent
What is simple schizophrenia?
Simple schizophrenia:
- Loss of drive and interest, aimlessness, idleness, self absorbed attitude and social withdrawal
- No hallucinations/delusions
In the pathophysiology of schizophrenia, which two brain pathways are thought to change?
- Mesolimbic pathway – thought to be overactive in schizophrenia
- Mesocortical pathway – thought to be underactive in schizophrenia
Describe the course of the mesolimbic pathway
- From: ventral tegmental area
- To: limbic structures (amygdala, septal area, hippocampal formation) and nucleus accumbens
Describe the course of the mesocortical pathway
- From: ventral tegmental area
- To: frontal cortex and cingulate cortex
Describe the brain changes observed in schizophrenia
- Enlarged ventricles
- Reduced hippocampal formation, amygdala, parahippocampal gyrus and prefrontal cortex
Describe the mechanism of action of typical antipsychotics in the treatment of schizophrenia
- Block D2 receptors in all CNS dopaminergic pathways
- Main action as antipsychotics is on mesolimbic and mesocortical pathways
Describe the mechanism of action of atypical antipsychotics in the treatment of schizophrenia
- Low affinity for D2 receptors
- Milder side effects as dissociate rapidly from D2 receptor
