Session 12 - Lecture 2: Psychosis

Question 1

Define psychosis.

Answer 1

Presence of hallucinations/delusions, this is not a diagnosis.

Question 2

Define delusion.

Answer 2

Abnormal belief outside of cultural norms, unshakeable.

Question 3

What are the diagnostic criteria for schizophrenia?

Answer 3

Need at least one of the following:-

• auditory hallucinations (running commentary/ thought echo).
• passivity experiences (action/feeling caused by external force).
• thought withdrawal, broadcast/insertion.
• delusional perceptions (new meaning to normally perceived object).
• somatic hallucinations (mimics feeling from inside body).

Question 4

List positive and negative symptoms of schizophrenia.

Answer 4

Positive symptoms = delusions, hallucinations, etc.

Negative symptoms = underactivity, social withdrawal and low motivation.

Question 5

What are the different types of schizophrenia an individual can have?

Answer 5

Paranoid (delusions/hallucinations).
Simple (loss of drive).
Hepebhrenic (sustained flattering/shallowness).
Undifferentiated 
Catatonic (unresponsiveness).

Question 6

Describe the pathophysiology of schizophrenia.

Answer 6

Mesocortical pathway - underactive from ventral temporal area to frontal and cingulate cortex.
Mesolimbic pathway - overactive from ventral segmental area to limbic structures.
Enlarged ventricles also present.

Question 7

What are the treatment options for schizophrenia?

Answer 7

Antipsychotics –> block D2 receptors e.g. haloperidol (many side effects).
Atypical antipsychotics –> bing and block with low affinity D2 receptors e.g. olanzapine (less side effects).
Both reduce cAMP, dopamine and therefore movement is reduces (basal ganglia circuits involved).

Question 8

If an increased level of dopamine (typical in individuals with schizophrenia) results in increased movement, why do some untreated patients develop catatonia?

Answer 8

Most likely due to reduced GABA binding so therefore this would result in a reduced inhibitory effect.

Question 9

What drugs can result in drug-induced psychosis?

Answer 9

Methamphetamine, cannabis, cocaine, amphetamines, LSD, ecstasy and ketamine.

Question 10

What is affective psychosis?

Answer 10

Psychotic experiences congruent with mood.

Question 11

What is post part psychosis?

Answer 11

Psychosis after having a baby, common if previous bipolar/psychotic illness, onset = days to weeks of delivery.