Lecture 18 - Basal Ganglia

Question 1

In the Basal Ganglia Striatum, the majority (95%) of the neurons are medium spiny ____-ergic projection neurons. Each neuron responds to dopamine differently depending on which dopamine receptors are more prevalent on them. If D1 are more prevalent, Dopamine is _______ (excitatory or inhibitory?). So what does that mean if D2 is more prevalent?

Answer 1

GABA-ergic

Excitatory

It means D2 is inhibitory

Question 2

5% of the Striatum is comprised of Giant Spiny neurons that are responsive to _____ instead of Dopamine.

Keep in mind neurons that are inhibited by Dopamine (majority D___ receptors), they will be excited by ____. So the opposite is true for majority D___ receptor neurons.)

Answer 2

ACH

D2

ACH

D1 –> Inhibited by ACH

Question 3

Globus Pallidus Interna (GPi) is the major output structure of the Basal Ganglia. At rest, it is ______ (highly or minimally?) active, discharging GABA onto the ______.

Answer 3

Highly active

Thalamus

Question 4

While Parkinson’s symptoms are caused by a loss of DA, Huntington disease symptoms are caused by loss of anatomy, specifically _____ neurons in the ____ head.

Keep in mind the _____ pathway is initially spared in Huntington disease, as the Globus Pallidus externa (GPe) is first affected.

Answer 4

D2 neurons

Caudate

Direct pathway

Question 5

_______ is a disorder caused by lesions to the Subthalamic Nucleus (STN)

Answer 5

Hemiballism