L11 - Schizophrenia Spectrum Disorders

Question 1

What is psychosis?

Answer 1

• Psychosis refers to loss of contact with external reality.

- Impaired perceptions and thought processes.

Question 2

What is Bleue’s (1911) ‘Split Mind’?

Answer 2

Refers to:

1) Fragmentation of thoughts.
2) Splitting of thoughts from emotions.
3) Withdrawal from reality.

Question 3

What are the DSM-5 Psychotic Disorders?

Answer 3

• Schizophrenia.
• Schizotypal (Personality) Disorder.
• Brief Psychotic Disorder (sudden, < 1 month).
• Schizophreniform Disorder (>1, <6 months).
• Schizoaffective Disorder.
• Substance/Medication-Induced Psychotic Disorder.
• Psychosis due to a medical cond.
• Catatonia & other unspecified.

Question 4

What is the criteria for DSM-5 Schizophrenia?

Answer 4

A: Characteristic symptoms. (≥2, during a 1 month period).

1. Delusions
2. Hallucinations
3. Disorganised speech (formal thought disorder)
4. Disorganised or catatonic behaviour
5. Negative symptoms

B: Impacts on social/occupational functioning.

C: Signs of disturbance for ≥6 months, at least 1 month of psychotic symptoms.

D-F: Not better explained by something else.

Question 5

What are the positive and negative symptoms of schizophrenia?

Answer 5

Positive symptoms: presence of problematic behaviours.

• Hallucinations
• Delusions
• Formal Thought Disorder
• Behavioural/Motor Disturbances
• Lack of insight

Negative symptoms: absence of healthy behaviours.
Affective flattening:
- Social withdrawal 
- Anhedonia
- Emotional blunting
- Confusion
Avolition:
- Amotivation
- Apathy
-Self-neglect
Alogia:
- Poverty of speech
- Poverty of content

Question 6

What are hallucinations?

Answer 6

Perception-like experiences that occur in absence of external stimulus.
75% of schizophrenics report hallucinations including:
- Auditory
- Visual (not illusion/misperception)
- Olfactory
- Gustatory
- Tactile

Question 7

What are auditory hallucinations?

Answer 7

• 60-70% of patients report auditory hallucinations.
• Hearing voices (distinct from own thoughts)
• From internal or external sources
• Can be comforting (tend to progress to derogatory/insulting)
• Commands to perform unacceptable behaviours.

Similar forms across cultures, but differences in content and interpretation.

Question 8

What are delusions?

Answer 8

• Firm false beliefs despite contrary evidence which are typically categorised based on content.
• Paranoid/Persecutory Delusions: false belief that one is being harmed by a person/group.
• Referential Delusions: neutral environment interpreted to have personal meaning.
• Grandiose Delusions: false belief of special powers/fame.
• Nihilistic Delusions: belief of non-existence of self, part of body, others, the world.
• Erotomanic Delusions: false belief that another person (stranger/celebrity) is in love with them.

Question 9

What is formal thought disorder?

Answer 9

• Disturbances in flow and/or form of speech (as opposed to content as in delusions).
• Negative manifestations (reduced stream of thought, speech poverty).
• Positive manifestations (derailment, circumlocution, tangential, echolalia, word salad, neologisms).

Question 10

What is the epidemiology of Schizophrenia?

Answer 10

• Lifetime prevalence: 1-2%
• Male:Female 3:2
• Typical onset in late adolescence (later for women)
• Onset coincides with a stressful life event

Question 11

What is the clinical course of Schizophrenia?

Answer 11

There is high variation in presentation and course.
Of those with chronic condition without full recovery:
- 50% unable to work
- < 25% employed
- social isolation, low income, poor health
- 30% attempt suicide
- 5-10% complete suicide.

Question 12

What are the implicated aetiological factors of Schizophrenia?

Answer 12

• Genetic
• Biochemical
• Neuroanatomical
• Psychosocial

Question 13

What are the genetic risk factors for Schizophrenia?

Answer 13

• 7% chance if siblings affected.
• 9% chance if 1 affected parent.
• 46% chance if both parents.
• 12% concordance for DZ twins.
• 44% for MZ twins.

Question 14

What are the biochemical risks factors for Schizophrenia?

Answer 14

Dopamine Hypothesis: overproduction or oversensitivity of dopamine receptors.

1. Excess L-Dopa in Parkinson’s Disorder precipitate psychotic episodes.
2. Amphetamine psychosis: abnormally large responses to low amphet. doses suggest over-sensitivity rather than excessive levels.
3. Response to anti-dopaminergic medication: effective in 60%, better for positive symptoms.
4. Lack of impact on negative symptoms.

Question 15

What does the lack of impact of anti-dopaminergic medication on negative symptoms suggest?

Answer 15

Hints at 2 seperate syndromes.

i) Caused by dopamine activity and associated with POSITIVE symptoms.
ii) Caused by brain degeneration and associated with NEGATIVE symptoms.

Question 16

What are the neuroanatomical risk factors for Schizophrenia?

Answer 16

• Enlarged ventricles (post-mortem, CT scans, MRI)
• Most likely cause is loss of brain tissue.
• Greater brain tissue loss is PFC is linked to negative symptoms.
• Smaller left hippocampal volume may be indicator.

Question 17

What are some seasonal and location relationships with Schizophrenia?

Answer 17

• Greater likelihood if winter or spring birth (Viral illness?; Vitamin D deficiency?).
• 2x as likely if urban birth.
• More common in low SES.

Question 18

What are the treatment options for Schizophrenia?

Answer 18

Medication is the primary intervention:

• 60% of patients with positive symptoms respond.
• 10-20% do not show any improvement.
• High 1 year relapse rate (40%).

Psychological interventions:

• CBT, Skills-based training, exercise, music treatment found to have benefit (Lutgens et al. 2017 Meta-analysis).
• Family Therapy Interventions: reduce relapse and enhance support.