Chapter 2

Question 1

Name the pathways and their associated tracts of the speech motor system

Answer 1

Final Common Pathway
Direct Activation Pathway
- corticobulbar and corticospinal
Indirect activation pathway
-corticoreticular and corticorubral
Control Circuits
-cerebellar and basal ganglia

Question 2

Final Common Pathway– what’s another name for it, why is it called “final common”?

Answer 2

aka LMN system
final– last link in chain of neural events before movement
common– all motor activity is mediated

Question 3

what types of nerves are involved in FCP?

Answer 3

cranial nerves and spinal nerves
cranial- phonation, resonance, articulation and prosody
spinal- breathing and prosody

Question 4

what cranial nerves are involved for the FCP?

Answer 4

V, VII, IX, X, XI, XII

Question 5

Direct Activation Pathway– what is another name for it, and what tracts does it divide into?

Answer 5

aka pyramidal tract or direct motor system
divided into:
-corticobulbar tract- cranial nerves V, VII, IX, X, XII
-corticospinal tract- spinal nerves (respiratory muscles)

Question 6

what do the 2 tracts of the DAP form?

Answer 6

part of the UMN system

Question 7

Unilateral lesions impacts what side of the body?

Answer 7

opposite/contralateral

Question 8

impact of UMN lesions for DAP

Answer 8

loss/reduction of skilled movement, more gross but no fine motor movement

Question 9

Unilateral UMN lesions often lead to what type of dysarthria?

Answer 9

unilateral UMN dysarthria

Question 10

Indirect Activation Pathway– what is another name for it, and why is it considered “indirect”?

Answer 10

aka extrapyramidal tract or indirect motor system

indirect– multiple synapses, primarily in brainstem

Question 11

what tracts does the IAP divide into?

Answer 11

corticoreticular- role in muscle tone

corticorubral- relay station from cerebellum to thalamus to cortex

Question 12

What is the function of the IAP?

Answer 12

help regulate reflexes and maintain posture, tone, and associated activities

Question 13

What do lesions in the IAP affect?

Answer 13

increased muscle tone (spasticity) and reflexes (hyperreflexia)

Question 14

how does the IAP support speech?

Answer 14

provides specific speech movements that can occur without interference and can maintain speed, range, and direction

Question 15

unilateral UMN lesion affecting IAP results in what type of dysarthria?

Answer 15

unilateral UMN

Question 16

bilateral UMN lesion affecting both direct and indirect pathways results in what type of dysarthria?

Answer 16

spastic

Question 17

What are the 2 control circuit pathways?

Answer 17

cerebellar and basal ganglia

Question 18

what are the two components of the Cerebellar Control Circuit (CCC)?

Answer 18

flocculonodular lobe and body of cerebellum

Question 19

what is the function of the CCC?

Answer 19

helps coordinate timing of movement, size of movement, and coordinates sequencing of agonists/antagonists

Question 20

damage to CCC results in what type of dysarthria?

Answer 20

ataxic dysarthria

Question 21

what is the function of the basal ganglia control circuit?

Answer 21

opens gates to intended movements and closing gates to competing or unwanted movements, and preventing “locking up” of movement

Question 22

damage to BGCC results n what?

Answer 22

reduced mobility (hypokinesia), involuntary movements (hyperkinesia)

Question 23

what type of dysarthrias do lesions of BGCC result in?

Answer 23

hypokinetic and hyperkinetic dysarthrias