Dopamine receptors

Question 1

What does hypofrontal mean?

Answer 1

When the PFC isn’t inhibiting properly, causing forgetfulness, inability to sustain attention, etc

Question 2

What are the two families of dopamine receptors?

Answer 2

D1 and D2

Question 3

What are the subtypes of the D1 family of receptors?

Answer 3

D1 and D5

Question 4

What are the subtypes of the D2 family of receptors?

Answer 4

D2, D3 and D4

Question 5

How is the Yerkes-Dodson law implicated in dopamine release?

Answer 5

Because stress increases the amount of dopamine in both of its pathways, and increases especially in the PFC

Question 6

What does giving a stimulant to someone who has ADHD cause?

Answer 6

It increases the levels of dopamine from too low back to the sweet spot concentration for optimal performance

Question 7

If DA is increased in the nigrostriatal pathway, it causes an increase in activity - how is it then, that giving a stimulant reduces activity in ADHD sufferers?

Answer 7

Because the mesocorticolimbic pathway has descending glutamate projection neurons that project to the negrostriatal pathway; this interacts with GABA interneuron in the nigrostriatum to actually inhibit DA in the nigrostriatal pathway

Question 8

What brain area is the main inhibitor?

Answer 8

The PFC

Question 9

Which DA pathway has the Yerkes-Dodson inverted U shape?

Answer 9

The mesocorticolimbic pathway (therefore, a stimulant in the mesocorticolimbic pathway can calm ADHD, but a stimulant in the nigrostriatal pathway does not increase activity)

Question 10

What does a higher amount of DA in the mesocorticolimbic pathway cause?

Answer 10

Increased PFC inhibitory effects, which then decrease the movements associated with the nigrostriatal pathway

Question 11

What can higher doses of ADHD medication do?

Answer 11

They can push DA past the sweet spot, override the PFC inhibitory system and increase hyperactivity in the nigrostriatal pathway