Basal Ganglia (2)

Question 1

What is the basal ganglia a collection of?

Answer 1

Gray matter nuclei located deep within the white matter of cerebral hemispheres

Question 2

What behaviors does the basal ganglia help regulate?

Answer 2

Reward

Motivation

Emotional

Social

Question 3

What are the main components of the basal ganglia?

Answer 3

Caudate nucleus

Putamen

Globus pallidus

Subthalamic nucleus

Substantia nigra

Question 4

What is the pathway of the basal ganglia?

Answer 4

Premotor cortex

Basal ganglia

Thalamus

Premotor cortex

Question 5

What does degeneration of the substantia nigra result in?

Answer 5

Parkinson’s (due to issues with dopamine production leading to movement dysfunction)

Question 6

How does the basal ganglia receive input?

Answer 6

Striatum

Question 7

How does output exit in the basal ganglia?

Answer 7

Internal segment of the Globus pallidus and substantia nigra pars compacta

Question 8

Where does the substantia nigra send neurons?

Answer 8

To striatum where they release dopamine

Question 9

What does a lesion to the basal ganglia result in?

Answer 9

Hypo/hyper kinetic movement disorders

Question 10

What is the role of the motor loop in the basal ganglia?

Answer 10

Muscle contraction and force

Multi joint movements

Sequencing of movements

Question 11

Why does the basal ganglia use indirect routes to LMNs?

Answer 11

Because it has no connections to the LMN

Question 12

What are the three indirect routes from the basal ganglia to the LMNs?

Answer 12

Motor thalamus

Pedunculopontine nucleus

Midbrain locomotor region

Question 13

What is the indirect pathway for the motor thalamus?

Answer 13

Basal ganglia inhibits motor thalamus

Motor thalamus facilitates lateral corticospinal and rubrospinal tracts

lateral corticospinal and rubrospinal tracts facilitates motor neurons to muscles for voluntary movement

Question 14

What is the indirect pathway of the pedunculopontine nucleus

Answer 14

Basal ganglia inhibits pedunculopontine nucleus

pedunculopontine nucleus facilitates reticulospinal tracts

Reticulospinal tracts facilitates motor neurons to postural and girdle muscles

Question 15

What is the indirect pathway of the midbrain locomotor region?

Answer 15

Basal ganglia inhibits midbrain locomotor region

midbrain locomotor region facilitates reticulospinal tracts

Reticulospinal tracts facilitate stepping pattern generators

Question 16

What is the role of the oculomotor loop in the basal ganglia?

Answer 16

Regulates spatial attention and eye movements (reflexive prosaccades)

Question 17

What is the role of the goal directed behavior loop in the basal ganglia?

Answer 17

Goal directed behavior

Makes perceptual decisions

Plans and decides on actions (decide how much time to get ready)

Question 18

What is the role of the social behavior loop in basal ganglia?

Answer 18

Recognition of social disapproval

Self control

Relevant vs irrelevant info

Maintaining attention

Stimulus response learning

Question 19

What is the role of the emotion loop in the basal ganglia?

Answer 19

Determines value of stimulus

Reward based behaviors

Monitors predictive errors and pleasure seeking (addiction)

Question 20

What does excessive inhibition in the basal ganglia result in?

Answer 20

Hypokinetic disorders (Parkinson’s)

Question 21

What does inadequate inhibition in the basal ganglia result in?

Answer 21

Hyperkinetic disorders (Huntington’s and Tourette’s)