Schizophrenia

Question 1

What is schizophrenia? what does it do? why is it caused?

Answer 1

is a disorder of abnormal thought, perception, behaviour, mood and attention
-Postive - delusions, auditory hallucinations

Negative - withdrawal, flattened mood

Why

• overactivity of dopamine systems in the mesolimbic system
• ventral tegemental area

Question 2

What can cause these schizophrenic symptoms and what is the evidence?

Answer 2

Increase dopamine and decreased glutamate

• Amohetamine - increase dopamine release - increase symptoms (drugs to block dopamine receptors reduce symptoms)
• Phencyclidine (PCP) - antagonist of glutamate receptor - so decreases glutamate - increase symptoms - however

Question 3

Anti-psychotic drugs - examples, how do they work? which symptoms do they work on? how long do they take to work?

Answer 3

Take 2-3 weeks to work (can try different drugs for different people)

Dopamine antagonists - chlorpromazine, haloperidol (mainly on positive symptoms)

Clozapine - very good for the negative symptoms of schizophrenia

• far higher affinity for D4 and D2
• side effects - decrease no. of neutrophils

Side effects
-show dyskinesias (parkinsons symptoms as blocking dopamine) - nigrastriatal pathway

Question 4

What is it?

Two types of depression

Answer 4

-Episodic, recurrent illness with periods of spontaneous remission

Unipolar - mood, appetitie, tiredness, negative self-concept
-endogenous or reactive depression - unknown or known origin

Bipolar - manic depression - strong genetic basis, mood fluctuates between depression and mania
-Mania - heightened mood/eurphoria, irritability, irational decisions, delusions sometimes

Question 5

Theory behind depression , reasoning behind

How do antidepressive drugs work on this?

Answer 5

Monoamine theory - loss of monoamines - noradrenaline, serotonin, dopamine

Cocaine - raises monoamine levels by blocking reuptake of monoamines –> increase mood

Antidepressants - produce an acute increase in brain monoamines by blocking reuptake or metabolism

How are monoamines inactivated - reuptake into neuron, breakdown by monoamine oxiadeses (however can take 2-6 weeks)

Question 6

Antidepressant drugs - unipolar depression

Answer 6

First gen - amitriptyline, imipramine
-block noradrenaline and serotonin re-uptake

Phenelzien - is a monoamine oxidase inhibitor (the enzyme that breaks down monoamides) - irreversible

Moclobemide - reversible monoamine oxidase inhibitor

Fluoxetine - potent selective serotonin reuptake inhibitor

Question 7

Drug treatment for bipolar drug treatment

Answer 7

Lithium carbonate - most effective treatment
-stabalises manic and depressive phases - overdose tremour, seizures

How
-dampens phosphoionsitide mediated neurotransmission

Question 8

Psychosis , hallucination

Answer 8

a severe mental disorder where reality is confused

Hallucination - a perception experienced in external space in the absence of a stimuli - cannot distinguish between reality

Dellusion - fixed false belief - know it is not real

If get persistant symptoms + loss of function = disorder

Question 9

How to treat schizophrenia

Answer 9

• drugs
• manage
• not just treating positive symptoms but also important to treat negative symptoms and reduce risk of relapse