Schizophrenia

Question 1

DSM-5

Answer 1

• criteria A: 2 or more of the following, at least 1 must be 1,2, 5
• 1) Delusions
• 2) Hallucinations
  -3) disorganised or catatonic beh
• 4) Beh symptoms (diminished emotion)
• 5) Disorganised speech

Question 2

Crow’s alternative classification system

Answer 2

• 2 types of SZ
• Type 1 pos symptoms (added) -> Hallucinations, delusions, fair prognosis, reversible, excess dopamine
  -Type 2 neg symptoms (taken away) -> affective flattening, speech poverty, poor prognosis/, structural issues, irreversible

Question 3

Structural Issues - Ventricle enlargement

Answer 3

• Lateral ventricle enlargement projecting out into temporal lobes
• Jacobi + winkler -> pneumoencephalography to remove cerebrospinal fluid found 18/19 had enlarged ventricles but side effects meant it was unethical (headache, death)
  -Johnstone et al First CAT scan of SZ showed large ventricles

Question 4

Ventricle enlargements - Temporal lobe

Answer 4

• crow et al-> enlargement confined to temporal horn + lobe which were predominantly on left Side of brain
• Barta et al -> relationship between left temporal gyrus size + severity of hallucinations, as gyrus volume decreases, hallucinations increase

Question 5

volume reduction- possible causes

Answer 5

• Thompson et al -> grey matter loss in adolescents with SZ parietal, temporal + frontal lobes

Question 6

Brain changes + time of onset

Answer 6

• Kemptom et al -> meta-analysis of 13 studies found ventricular dilation begins before or shortly after birth

Question 7

SZ + urbanisation

Answer 7

• Torrey + Bowler- reflecting aspects of social upheaval +stresses during industrial revolution
• most urbanised area most Sz cases

Question 8

Neural migration

Answer 8

• Bracha et Al -> neural migration responsible for fingerprints
• Fingerprints of twins with SZ very different

Question 9

FlU + SZ

Answer 9

• Medrick et dl-> those in 2nd trimester during flu epidemic more likely to dev SZ than matched controls

Question 10

Retrovirus + SZ

Answer 10

• monkey virus - Lillinoj et al found evidence for retrovirus activity in 29% of SZ patients compared with 3% of controls
  -Karlsson et al (2001) found HERV-W retrovirus active in SZ patients

Question 11

DSM-5 delusions

Answer 11

• fixed beliefs
• grandeur: belief you have special power/ world figure
• persecution: belief others are plotting against them
• Thought insertion : belief others placing thoughts in head
• Broadcasting : belief own thoughts broadcasted Out loud

Question 12

DSM-5 Hallucinations

Answer 12

• Auditory: most common
• voices saying unpleasant things
  visual may be of people/objects not really there

Question 13

Dopamine Hypothesis + Ampretamine

Answer 13

• Amphetamine boosts synaptic Levels of dopamine
• symptoms resemble paranoid (Type 1) SZ: auditory hallucinations, delusions, thought alienations

Question 14

treatment : Neuroleptics

Answer 14

• Delay + Deniker- first report use of chlorpromazine which had calming effect on agitation
• dopamine receptor blockage May be basis of therapeutic effects of neuroleptics

Question 15

Clinical description

Answer 15

• Lifetime prevalence is 1% + affects slightly more men
• Appears in late adolescence, early adulthood

Question 16

Avolition - Neg symptom

Answer 16

• Diminished motivation

Question 17

Asociality - Neg symptom

Answer 17

• severe impaired relationships
• want to be alone
• don’t desire close relationships

Question 18

Anhedonia - Neg symptom

Answer 18

• loss of experience/ interest of pleasure
• kring et al -> have deficit in anticipatory ( expected) pleasure but can experience pleasure

Question 19

Blunted Affect- Neg symptom

Answer 19

• Lack of outward expression of emotion
• motionless face
• flat, toneless speech

Question 20

Alogia - Neg symptom

Answer 20

• sig reduction in speech
• answer questions with 1/ 2 words

Question 21

Disorganised speech - Disorganised symptom

Answer 21

• problems organising ideas + speaking clearly
• loose associations

Question 22

Disorganised beh - disorganised symptoms

Answer 22

• inexplicable bouts agitation, act silly
• lose ability to organise beh
• catatonia - gesture repeatedly

Question 23

Brief psychotic disorder

Answer 23

• same symptoms as SZ but only last a few months
• TO diagnose SZ must last 6 months

Question 24

Genetic Influence

Answer 24

• Andreasen et al-> heritability of SZ is 0.77

Question 25

Genetics research - family studies

Answer 25

-relatives of people with SZ are at higher risk - risk increases as genetic relationship grows closer - MZ twins 44.30 % - DZ twins = 12.08 % - sibling = 7.30 - children = 9.35 - Laursen et al > incidence of SZ was highest for children with both parents having SZ

Question 26

Genetic research- Twin studies

Answer 26

- meta-analysis of 12 studies concluded that there is high heritability but also evidence of small but sig ENV contribution (Sullivan, Kendler) - family + twin studies have shared + non-shared env factors

Question 27

Genetic research- Adoption studies

Answer 27

- children who bio mother had SZ but were adopted eliminates effects of being reared in env with SZ -Heston -> 10.6% developed SZ

Question 28

Molecular genetic research

Answer 28

-multiple genes associated with SZ -25 candidate genes for SZ - one is DRD2 (werge) encodes specific D2 dopamine receptor - genome-wide study found over 50 variation mutentions were 3x more common in SZ (McClellan) - only some people with rare mutation have SZ

Question 29

Dopamine Theory

Answer 29

- SZ related to excess activity of dopamine NT - based on drugs effective in SZ reduce dopamine - too simple to explain range of symptoms -excess dopamine is related to pos disorganised symptoms

Question 30

other NT

Answer 30

- MoIski et al treatment blocking serotonin 5HT2 recepter -low glutamate found cerebrospinal fluid of SZ - Bressan et al -> brain imaging shows decreased NMDA receptor (glutamate system)

Question 31

Prefrontal cortex + SZ

Answer 31

- known to play a role in beh ( speech, emotion) that are disrupted in SZ - MRI shows reduced grey Matter in prefrontal cortex -dendritic spines may be lost meaning communication disisupted

Question 32

connectivity

Answer 32

- SZ have less connectivity in White matter in frontal + temporal cortices -Assoc with genetic vulnerability of SZ -less connectivity between frontparietal + Default mode networks correlated with neg symptoms

Question 33

Excessive pruning

Answer 33

- cannon -loss of synapses - loss of necessary communication

Question 34

treatment - medication

Answer 34

- Antipsychotics help some symptoms -people who respond pos are kept on maintenance dose to continue effect - common side effects = sedation, dizziness, blurred viSion - extrapyramidal side effeits resemble Parkinson disease

Question 35

Treatment- first gen antipsychotics

Answer 35

- first discovered -reduce pus + disorganised -no effect on neg - 30 % don't respond - common side effects: extrapyramidal (PD), drowsiness, restlessness - chlorpromazine

Question 36

Treatment- second -gen antipsychotics

Answer 36

- side effects: extrapyramidal (PD) , drowsiness, weight gain , insomnia, headache - clozapine - second gen more effective - second gen produce fewer side effects - Not very effective at reducing neg symptoms