Lecture 12

Question 1

The basal nuclei consists of paired nuclei. What are these nuclei?

Answer 1

Striatum (caudate nucleus, putamen), globus pallidus, substantia nigra, and subthalamic nucleus

Question 2

What is the function of the putamen circuit? Is this circuit direct or indirect?

Answer 2

Function is not totally clear, but it does inhibit athetosis/non-volitional movements; suppresses rigidity; for subconscious execution of learned patterns of movement

Direct

Question 3

What is the function of the caudate nucleus circuit? Is this circuit direct or indirect?

Answer 3

Involved in motor planning; activating muscles in sequence for motor patterns 5 seconds ahead or more

Indirect

Question 4

Need to review the pathways for the circuits

Answer 4

RIP

Question 5

What do lesions in the subthalamic nuclei result in?

Answer 5

Results in the release of inhibition on the contralateral side; results in sudden, flailing movements of an entire limb (hemiballismus)

Question 6

What do lesions in the striatum result in? What disease is this associated with?

Answer 6

Results in the release of inhibition; results in flicking movements in hands, face, or elsewhere (chorea)

Occurs in patients with Huntington’s Disease

Question 7

What do lesions in the substantia nigra result in? What disease is this associated with?

Answer 7

Results in rigidity, akinesia (serious difficulty in initiating movement), and tremors; since dopamine inhibits the indirect (inhibitory) pathway and excites the direct (excitatory) pathway, destruction of the dopaminergic neurons results in an overall inhibitory effect

Occurs in patients with Parkinson’s Disease

Question 8

What neurotransmitter is used when going from the substantia nigra to the caudate nucleus and putamen? Is it inhibitory or excitatory?

Answer 8

Dopamine; inhibitory

Question 9

What neurotransmitter is used when going from the caudate nucleus and putamen to the globus pallidus and substantia nigra? Is it inhibitory or excitatory?

Answer 9

GABA; inhibitory

Question 10

What neurotransmitter is used when going from the cortex to the caudate nucleus and putamen? Is it inhibitory or excitatory?

Answer 10

Acetylcholine; excitatory

Question 11

What neurotransmitters are used when going from the brain stem in various pathways?

Answer 11

Norepinephrine, serotonin, enkephalin