Schizophrenia spectrum disorders

Question 1

Definition of psychosis?

Answer 1

Grossly impaired reality testing - make incorrect inferences about external reality, even in the presence of contrary evidence

Question 2

What are the “classic” features of schizophrenia spectrum disorders?

Answer 2

1. Delusions
2. Hallucinations
3. Disordered thinking (manifests in speech)
4. Grossly disorganised/abnormal motor behaviour (incl. catatonia)
5. Negative symptoms

Question 3

Contrast between positive, negative and disorganised symptoms - pathophysiology, prognosis, examples?

Answer 3

Positive:

• Biochemical or functional disturbances
• More amenable to pharmacological management
• E.g. Delusions, hallucinations, thought disorder

Negative:

• Correlates with structural changes to the CNS
• Less responsive to pharmacological treatment
• E.g. Avolition, alogia, anhedonia, asociality, affective blunting

Disorganised:

• Thought disordered
• Disturbances of behaviour

Question 4

Outline the dopaminergic pathways in the brain

Answer 4

• Mesolimbic: behaviour “reward pathway”; related to positive symptoms
• Nigrostriatal: co-ordination of voluntary movement; inhibition results in EPSE’s
• Mesocortical: involves behaviour and motivation; related to negative symptoms
• Tuberoinfundibular: tonic inhibition of prolactin release

Question 5

Definition of delusions

Answer 5

Fixed, false beliefs that are not amenable to change, even in light of conflicting evidence

Question 6

Types of delusions?

Answer 6

Bizarre - implausible and not understandable to same-culture peers, and do not derive from ordinary life experiences
Thought withdrawal
Thought insertion
Delusions of control - body/actions are being controlled by an external force

Question 7

Themes of delusions?

Answer 7

Persecutory - going to be harmed, harassed etc
Grandiose - has exceptional abilities, wealth, fame etc
Somatic - preoccupations with health and organ function
Religious
Referential - gestures, comments etc are directed at them
Erotomanic - another person is in love with them
Nihilistic - major catastrophe will occur

Question 8

Definition of hallucinations

Answer 8

Perception-like experiences that occur in the absence of an external stimulus. They occur with the full force and impact of normal perceptions. They aren’t under voluntary control. Must occur in context of clear sensorium, and be differentiated from illusions and distortions

Question 9

Definition of illusions

Answer 9

False or misinterpreted perceptions of real stimuli

Question 10

Definition of distortions

Answer 10

Changes in intensity, quality or form of sights, sounds or self-perception (includes derealisation and depersonalisation)

Question 11

Types of hallucinations

Answer 11

Auditory (most common)
Visual
Tactile
Gustatory
Command
Somatic
Olfactory

Question 12

What is a pseudohallucination?

Answer 12

An involuntary sensory experience, vivid enough to be regarded as a hallucination, but which is recognised by the patient not to be due to external stimuli i.e. they are recognised to be unreal. e.g. hearing voices inside their head, and recognising they aren’t coming from the outside world

Question 13

What is a parahallucination?

Answer 13

Hallucinations that occur due to an injury or abnormality to the peripheral nervous system

Question 14

What is meant by disordered thinking, and how is this recognised?

Answer 14

A formal thought disorder is inferred from the individual’s speech. It must be severe enough to substantially impair effective communication. NB: recognition of this may be biased by the assessor/patient’s linguistic background

Question 15

Examples of thought disorder?

Answer 15

• Derailment/loosening of associations
• Tangentiality
• Circumstantiality
• Word salad/incoherence

Question 16

Derailment/loosening of associations?

Answer 16

No logical or meaningful connection between one idea and another - a sudden, peculiar change of topic in otherwise logical speech
[switching between topics]

Question 17

Tangentiality?

Answer 17

Deviation form the central idea or question - represents an inability to answer to the point
[answers to questions may be obliquely related or completely unrelated]

Question 18

Circumstantiality?

Answer 18

The train of thought is filled with numerous digressions before the central idea is finally reached

Question 19

Word salad/incoherence?

Answer 19

Incomprehensible speech resembling receptive aphasia

Question 20

Definition of grossly disorganised or motor behaviour

Answer 20

May manifest in a variety of ways, ranging from child-like silliness, the unpredictable agitation. Problems with goal-directed behaviours, leading to difficulties in ADLs. Includes catatonia

Question 21

Definition of catatonia?

Answer 21

A behavioural disorder/syndrome, of altered awareness to the external environment, with either decreased mobility to complete unawareness, or excessive unstimulated psychomotor activity (catatonic excitement). Catatonic symptoms may occur in other psychiatric illnesses, or secondary to a medical illness

Question 22

Features of catatonia, according to DSM V

Answer 22

decreased
1. Stupor
2. Mutism
3. Waxy flexibility
4. Catalepsy
5. Negativism
6. Posturing
_______________________________________
increased
7. Mannerism
8. Stereotypy
9. Agitation
10. Grimacing
11. Echolalia
12. Echopraxia

Question 23

Definition of negative symptoms?

Answer 23

Reflect a decrease in, or loss of, normal functions. Account for a substantial portion of the morbidity associated with schizophrenia, but are less prominent in other psychotic disorders

Question 24

What are the negative symptoms?

Answer 24

5 A’s:

• Alogia: decreased speech output
• Anhedonia: decreased ability to experience pleasure
• Avolition: decrease in motivated self-initiated, purposeful activities
• Asociality: lack of interest in social interactions
• Affective blunting