12b.) Psychosis Flashcards
What is psychosis?
- Presence of hallucination or delusions
- Describes symptoms, not a diagnosis itself
What are hallucinations?
Perceptions without a stimulus. They can be in any sensory modality e.g. hearing voices, seeing things…
Visual hallucinations are usually organic; true or false?
True (by organic we mean caused by sort of physcial definable problem such as one with eyes or brain)
Hallucinations are normal when going to sleep and/or waking up; what do we call the hallucinations that occur when you:
- Go to sleep
- Wake up
What are delusions?
Fixed false belief which is unshakeable and is outside of cultural norms.
*NOTE: normal for some cultures to believe in e.g. witchcraft so this wouldn’t be a delusion
Patients with schizophrenia don’t have split mind or personality; true or false?
TRUE; common misconception that they have split mind/personality
*Other common misconceptions include: patients with shcizophrenia are more dangerous than other patients
Kurt Schneider came up with the first rank symptoms for shizophrenia; state the 5 first rank symptoms
- Auditory hallucinations
- Passitivity experiences
- Thought withdrawal, broadcast or insertion
- Delusional perceptions
- Somatic hallucinations
Describe the 3 types of auditory hallucinations
- Thought echo: hearing thoughts aloud
- Running commentary: e.g. he is brushing his teeth
- Third person: voices referring to the patient in 3rd person and conversing with each other about the patient
What are passitivity experiences?
Patient believes an action or feeling is caused by an external force e.g. MI5 have been moving my leg
Describe:
- Though withdrawal
- Thought broadcast
- Thought insertion
- Thought withdrawal: thoughts are being taken out of the mind
- Thought broadcast: everyone knows what the person is thinking
- Thought insertion: thoughts implanted by others
What are delusional perceptions?
When someone attributes a new meaning, usually in the sense of self-reference, to a normally perceived object
What are somatic hallucinations?
Mimics feelings from inside body e.g. feels like heart is twisting
Schizophrenia has both positive & negative symptoms; state the symptoms in each category
Which symptoms of schizophrenia are more difficult to treat; positive or negative?
Negative are more difficult to treat and patients often are treated for/no longer have positive symptoms but are left with the negative symptoms
All patients with schizophrenia are different; true or false?
True
Describe the dopamine theory of shcizophrenia, include:
- Whether dopamine is too low or too high
- Evidence for the above
- Two major dopamin pathways thought to be involved
- What is abnormal about these two pathways
- Dopamine is too high/in excess
- Evidence:
- All medications that antagonise DA receptors help treat psychosis and those with strongest affinity for D2 receptors are most clinically effective
- Drugs e.g. amphetamines which cause release of DA cause psychotic symptoms
- Mesolimbic pathway (overactive) and mesocortical pathway (underactive)
State where the mesolimbic pathway (one of the dopamine pathways) goes from and to
State where the mesocortical pathway (one of dopamine pathways) goes from and to
State the 4 brain changes seen in schizophrenia
- Enlarged ventricles
- Reduced grey matter (with reduced brain weight)
- Decreased temporal lobe volume (thought to be responsible for auditory hallucinations)
- Reduced hippocampal formation, amygdala, parahippocmapla gyrus & cortex
Describe the neuropathology of schizophrenia
Why is it thought that limbic structures & basal ganglia are involved in schizophrenia?
Where are D2 receptors found in CNS?
State where the nigrostriatal pathway is from and to
Explain why antipsychotics, particularly typical antipsychotics, can cause parkinsonism
- Antipsychotics= dopamine antagonists
- Inhibit actions of dopamine
- Act on all dopamine receptors in CNS (but note that atypical antipsychotics have less affinity for D2 receptors and much less likely to cause parkinsonism symptoms)
- Dopamine in nigrostriatal pathway involved in movement (partiucularly in initiation & ceasing of movement)
- Less dopamine acting on putamen due to antipsychotics = less movement
