Biological reasons of Sz

Question 1

• Dopamine is a neurotransmitter
• Plays a part in Parkinson’s disease
• L dopa increases Dopamine levels in the brain resulting in schizophrenic symptoms
• LINK

Answer 1

Initial Hypothesis came from this

Question 2

Initial Hypothesis

• too much Dopamine = symptoms of schizophrenia
• Heavily Criticised as reducing Dopamine levels in schizophrenics with negative symptoms did not have any effect on behaviour

Answer 2

• could only explain positive symptoms

Question 3

• Different subtypes of receptors
• D1-D5
• But D2 is mainly focused upon as it is found in the limbic system

Answer 3

• there are two pathways in the limbic system which the D2 receptor is commonly found

Question 4

• Limbic System
• Mesolimbic
• Mesocortical

Answer 4

• Mesolimbic - too much Dopamine causes overstimulation = positive symptoms
• Mesocortical - too little Dopamine causes dysfunction = negative symptoms
• davies et al (1991)