Dopamine hypothesis Flashcards
(17 cards)
What is the dopamine hypothesis?
Excess levels of dopamine may cause schizophrenia
What happens to the neurones using dopamine transmitetrs?
The fire too often, too quickly and send too many signals
What receptors play a key role?
Some D2 receptors
What kind of explanation is the dopamine hypothesis?
A biochemical one
What happens to the D1 receptors?
There isn’t enough dopamine in the brain
What is one area of evidence?
Excess levels of dopamine in those with parkinsons
What happens to those with parkinsons?
They don’t have enough dopamine, given L-Dopa to increase levels, causes parkinsons symptoms to subside, however if it gets too high it can cause schizophrenic symptoms
What is the revised dopamine hypothesis?
Recent years, new pathways have been discovered
What are the two pathways that have been recently discovered?
Mesolimbic and mesocortical
What receptors does the mesolimbic pathway use?
D2 receptors
What happens at these receptors?
Too many signals hit them so they become saturated and inhibited, dopamine remains for longer
What symptoms are caused at the mesolimbic pathway?
Positive symptoms
What receptors does the mesocortical pathway use?
D1 receptors
What happens at these receptors?
There isn’t enough dopamine in the brain
What symptoms are caused at the mesocortical pathway?
Negative and cognitive
Where does dopamine move from and to in the mesolimbic pathway?
VTA to the NA
Where does dopamine move from and too in the mesocortical pathway?
VTA to the frontal lobe
