Basal Ganglia

Question 1

What are the functions of BG?

Answer 1

facilitate and inhibit movement
learning of motor tasks

Question 2

Is there a direction connection with LMNs with BG?

Answer 2

NO

Question 3

What activity does BG adjust?

Answer 3

Descending tracts

Question 4

What are the primary input nuclei’s of BG?

Answer 4

Caudate and Putamen

Question 5

What is the primary output nuclei of BG?

Answer 5

Globus Pallidus

Question 6

What makes up the striatum?

Answer 6

Caudate and Putamen

Question 7

What makes up the Lentiform Nucleus?

Answer 7

Putamen and Globus Pallidus

Question 8

What modulation is lost in Parkinson’s Disease?

Answer 8

Amount and type of output sent to the globus pallidus (and to the cortex)

Question 9

If the subthalamic nucleus is damaged, what movements are seen?

Answer 9

Explosive (Ballism)

Question 10

Role of Dorsolateral Prefrontal Circuit

Answer 10

Executive functions
Organizing behavior responses, problem solving

Question 11

Role of Lateral Orbitofrontal Circuit

Answer 11

Mediating empathetic and socially appropriate responses

Question 12

Disorder from dysfunction of Lateral Orbitofrontal Circuit (LOC)?

Answer 12

OCD, Schizophrenia

Question 13

Role of Anterior Cingulate Circuit?

Answer 13

Motivated behavior
Procedural learning

Question 14

Parkinson’s Disease vs Parkinsonism

Answer 14

PD = putamen can’t be activated secondary to loss of dopamine input from substantia nigra

“ism” = damage to putamen or globus pallidus

Question 15

Name the two motor loops of the basal ganglia?

Answer 15

Direct Motor Pathway
Indirect Motor Pathway

Question 16

Which pathway facilitates movement?

Answer 16

Direct Motor

Question 17

Which pathway inhibits movement?

Answer 17

Indirect Motor

Question 18

Sensorimotor Areas (M1, SMA, PMC, S1) project to?

Answer 18

Putamen

Question 19

Association Areas (Prefrontal cortex, frontal eye fields) project to?

Answer 19

Caudate

Question 20

Limbic Areas project to?

Answer 20

Putamen

Question 21

Hypokinesia is due to ____ inhibition of thalamus by BG and _____ excitation of motor cortex

Answer 21

Increased Inhibition
Decreased Excitation

Question 22

Hyperkinesia is due to ____ inhibition of thalamus by BG and _____ excitation of motor cortex

Answer 22

Decreased Inhibition
Increased Excitation

Question 23

What is lost in the indirect pathway that leads to chorea (ex, Huntington’s Disease)?

Answer 23

Striatal neurons lost, direct pathway released

Question 24

What explains the initial motor symptoms in PD?

Answer 24

Putamen is affected first (primarily motor)

Question 25

What explains the cognitive impairments presented later in PD?

Answer 25

Caudate is affected (cognition)

Question 26

Dystonia Definition

Answer 26

Neurological syndrome by sustained muscle contractions that causes twisting repetitive movements, abnormal posture

Question 27

Pathogenesis of Dystonia (2)

Answer 27

1. Defect of descending pathways that results in reciprocal inhibition of motor neurons 2. Chemical dysfunction in BG

Question 28

In dystonia there is a co-contraction of what muscles?

Answer 28

Agonist and Antagonist