SCHIZOPHRENIA

Question 1

Schizophrenia positive symptoms

Answer 1

abnormal behaviours that have been GAINED

• hallucinations (typically audio)
• delusions (paranoia)
• thought disorder - psychosis

Question 2

Schizophrenia negative symptoms (LOST)

Answer 2

blunted emotional responses 
poverty of speech 
social withdrawal 
lack of insight 
cognitive deficits 
anhedonia

Question 3

many functions mediated by ____ are impaired in schizophrenia

Answer 3

PFC

Question 4

is schizophrenic genetic

Answer 4

yes odds of developing it incraeases if one relative has schizophrenia

Question 5

DISC1 gene

Answer 5

mutation linked to risk of schizophrenia

encodes for proteins essential in neural development

Question 6

perinatal complications leading to schizophrenia

Answer 6

poor nutrition during pregnancy
premature birth/low birth weight
physical/immune stressors e.g. infections

Question 7

behaviours in early infancy that signal potential risk of schizophrenia

Answer 7

passivity and apathy
reduced responsiveness to verbal commands
difficult temperament
poor sensorimotor performance

Question 8

during adolescence, what occurs in schizophrenic patients

Answer 8

excessive synaptic pruning leading to loss of cortical grey matter

Question 9

hippocampus in schizophrenia

Answer 9

have enlarged ventricles due to smaller hippocampus and other temporal lobe regions.

Question 10

prefrontal cortex in schizophrenia

Answer 10

pyramidal neurons have reduced # of dendrites. reduces processing power and leads to connectivity failures.
hyperfrontality (reduced pFC function)

Question 11

GABAergic interneurons

Answer 11

major information filter for PFC and are reduced for schizophrenics. leads to noisy cortex, reduced information filtering and impaired functioning of these regions.

Question 12

The dopamine hypothesis

Answer 12

schizophrenia is caused by abnormal increase in dopamine transmission leading to overstimulation of D2 receptors.

Question 13

support for DA hypothesis

Answer 13

1. chlorpromazine is an antipsychotic. causes Parkinsons symptoms in healthy individuals
2. drugs that increase DA release like amphetamines induce psychotic symptoms
3. Antipsychotics found to block DA receptors, specifically D2 receptors.
4. DA release is hypersensitive in schizophrenia (found through imaging and administering amphetamine)

Question 14

What does DA do in schizophrenia

Answer 14

Hyperactive DA system may tag normally irrelevant stimuli as important and impair filtering out irrelevant stimuli.
leads to delusions.

Question 15

Dopamine imbalance hypothesis

Answer 15

symptoms are due to reduced prefrontal DA function (negative/cognitive symptoms) combined with excess mesolimbic DA function (positive symptoms)

Question 16

support for DA imbalance hypothesis

Answer 16

1. evidence of reduced PFC DA transmission in schizophrenia

2. increase PFC DA release improve cognitive functions

Question 17

The glutamate hypothesis of schizophrenia

Answer 17

schizophrenia is caused by decreased glutamate transmission

Question 18

support of Glutamate hypothesis

Answer 18

1. degeneration of glutaminergic/hippocampal neurons is apparent in schizophrenia. could disrupt functioning of these cells and lead to less glutamate transmission
2. non competitive NMDA antagonist induce psychotic symptoms and cognitive deficits in healthy individuals, exacerbate symptoms in schizophrenic patients.