Psychosis

Question 1

What is the definition of psychosis?

Answer 1

The presence of hallucinations or delusions

Describes symptoms - not a diagnosis in itself

Question 2

What are hallucinations?

Answer 2

Perception without stimulus

can be any sensory modality

Visual hallucinations are usually organic (problem with brain or eyes), auditory hallucinations very common in psychosis

Question 3

What are the 2 types of hallucination experienced by ‘normal’ population?

Answer 3

Hypnogogic - when going to sleep

Hypnopompic - on waking up

Question 4

What are delusions?

Answer 4

A false belief which is unshakable and outside of cultural norms

e.g. religion is not a delusion

Question 5

What are the first rank symptoms seen in patients with schiziphrenia?

Answer 5

• Auditory hallucinations
• Passivity experiences
• Though withdrawl, broadcase or insertion
• Delusional perceptions
• Somatic hallucinations

Question 6

What are the different forms of auditory hallucination?

Answer 6

Thought echo: hearing thoughts aloud

Running commentary: on what the patient is doing e.g . ‘He is brushing his teeth’

Third person: voices talking amounst themselves or talking directly to the patient

Question 7

What are passivity experiences experiencesd in schizophrenia?

Answer 7

The patient believes an action or feeling is caused by an external force

e.g. ‘MI5 have been moving my leg’

Can be a very frightening feeling

Question 8

What is thought withdrawl, broadcast or insertion?

Answer 8

• Thought withdrawl - thoughts are being taken out of the mind
• Thought broadcast - everyone knows what the person is thinking
• Though insertion - you think the thought has been implanted by others

Question 9

What is delusion perception?

Answer 9

Where the patient attributes a new meaning to a usually normally percieved object.

E.g. The traffic light going red means aliens are going to land soon

Question 10

What are somatic hallucinations?

Answer 10

Patients can feel things ‘inside’ their body e.g. feel their internal organs moving

Question 11

What is the difference between positive and negative hallucinations experienced by someon with schizophrenia?

Answer 11

Positive symptoms: symptoms gained

• delusions
• hallucinaions
• thought disorders
• lack of insight

Negative symptoms: thinks that take away from the patients

• underactivity
• low motivation
• social withdrawl
• emotional flattening (don’t engage emotionally with people)

Question 12

Explain the dopamine theory of schizophrenia

Answer 12

Drugs that cause the release of dopamine induce psychotic symptoms

All medications that antagonise DA receptors help treat psychosis. The strongest affinity being D2 receptors

Question 13

What are the 4 dopamine pathways in the brain?

Answer 13

Mesocortical: thought to be underactive in schizophrenia (responsible for negative symptoms)

Mesolimbic: thought to be overactive in schizophrenia

Nigrostriatal

Tuberinfundibular

Question 14

What brain changes are seen in a schizophrenic brain?

Answer 14

• Enlarged ventricles
• Reduced grey matter (reduced brain weight)
• Decreased temporal lobe volume (thought to be why auditory hallucinations occur)
• Reduced hippocampal formation, amygdala, parahippocampal gyrus and prefrontal cortex

Question 15

What brain changes have lead to the aberrant connectivity theory of schizophrenia?

Answer 15

• Decreased pre-synaptic markers
• Decreased oligodendroglia
• Fewer thalamic neurones

Question 16

How do typical antipyschotics treat schizophrenia?

Answer 16

Dopamine antagonists

• Block D2 receptors in all CNA dopaminergic pathways
• Mainly act on mesolimbic and mesocrotical pathways but side effects come from antagonising D2 receptors in other pathways
  
  • can get Parkinson like symptoms

Question 17

How do atypical antipsychotics work?

Answer 17

• Lower affinity for D2 receptors
• Milder side effects as rapidly dissociated from D2 receptor
• Block 5HT2 receptors
• Can cause impaired glucose tolerance, weight gain and prolonged QT

Question 18

Where in the brain are D2 receptors mainly located?

Answer 18

• Striatum
• Substantia nigra
• Pituitary gland

Question 19

What is catatonia? (Develops in patients treated with dopamine for schizophrenia- rarer now than it used to be)

Answer 19

More than 2 weeks, one or more of abnormal movement:

• Stupor/ mutism
• Excitement
• Posturing
• Negativism
• Rigidity
• Waxy flexibility
• Command Automatism

Though to be due to less GABA binding so loss of inhibitory effect

Question 20

What are some of the side effects of antipsychotics that antagonise Dopamine, and why?

Answer 20

Dopamine normally inhibits prolactin release from pituitary. DA antagonists recude dopamines inhibitory functions, therefore leading to increased prolactin levels

Can lead to:

• Amenorrhoea
• Galactorrhoea
• Decreased fertility
• Reduced libido
• Long term can cause osteopenia/ osteoporosis

Question 21

What are some of the difficulties in treating a schizophrenic patient?

Answer 21

• They lack insight - don’t believe they’re unweel so hard to convince to treat
• Medications therefore not taken (especially if they believe the Dr is part of their hallucinations)
• Medications can be given as short acting IM but this means may need pinning down several times a day, or given as depot injection

Question 22

What are some good prognostic factors for treating someone with schizophrenia?

Answer 22

• No family history
• Good premorbid function
• Acute onset
• Mood disturbance
• Prompt treatment
• Maintenance of therapy

Question 23

What is the prognosis of patients with schizophrenia?

Answer 23

• Mortality x2 as hight than general population
• Shorter life expectancy
• Incidence of CVS, respitory disease and cancer is higher
• Suicide risk is x9 higher than the general population
• Death from violent incidences x2 as high
• 50% have a substance misuse problem
• Higher rate of smoking