Direct/Voluntary and Indirect Motor Pathways

43 terms by melikajones 

Create a new folder

Advertisement Upgrade to remove ads

What is the direct activation pathway also known as?

Pyramidal tract
Direct motor system

What does the direct activation pathway have a major influence on?

Final Common Pathway

What is the pyramidal tract divided into?

corticobulbar tract
corticospinal tract

What does the pyramidal system carry?

UMNs

What is the system that provides innervation to voluntary/striated muscles?

Pyramidal system

What is the origin of LMN?

brainstem and spinal cord

What is the destination of LMN?

muscle

What is the function of LMN?

produce muscle actions for reflexes and muscle tone
carry out UMN commands for voluntary movements and postural adjustments

What are some distinctive signs of a LMN lesion?

1) weakness of all movements (voluntary & automatic)
2) Diminished reflexes
3) Decreased muscle tone
4) atrophy
5) fasciculations

What does the UMN consist of?

Direct and Indirect activation pathways
AKA pyramidal and extrapyramidal

What is the Direct Activation Pathway (pyramidal) and Indirect Pathway (extrapyramidal) Origin?

Cerebral cortex

What is the Direct Activation Pathway and Indirect Activation Pathway destination?

cranial and spinal nerve nuclei

What is the function of the Direct Activation Pathway (Pyramidal)?

direct
Voluntary
Skilled Movements

What are some distinctive signs of pyramidal lesions?

loss of skilled movement
hyporeflexia
babinski sign
decreased muscle tone

What is the function of the Indirect Activation Pathway or Extrapyramidal pathway?

control posture, tone, & movements supportive of voluntary movement

What are some distinctive signs of lesions to the extrapyramidal or indirect activation pathway?

spasticity
clonus
hyperactive stretch reflexes
increased muscle tone
extended legs with resistance to bending (decorticate posturing)
excitation of all extensor muscles (decerebrate posturing)

The direct and indirect activation pathways, as well as the control circuits, are all part of the _______

UMN system

Where is the UMN system contained?

CNS

What is NOT included in the UMN system?

The UMN system does NOT include the basal ganglia and cerebellar control circuits

What connects the cortex to the FCP?

direct activation pathway or pyramidal tract

Where does the direct activation pathway originate?

primary motor cortex (AKA, precentral gyrus, motor strip, or Brodmann's area 4)

What are the focal points of the pyramidal tract for speech?

primary motor cortex
premotor cortex
supplementary motor area
postcentral gyrus

On the premotor cortex, where are the cell bodies that innervate muscles of the face, including tongue, larynx, palate, jaw, face located?

lowest portion of the premotor cortex

What is the innervation of UMN pathways primarily?

LMN's contralateral (to the opposite side)

What direct activation pathway innervation is bilateral?

CN 5 - Trigeminal
CN 7 Upper Face only
CN 9 - Glossopharyngeal
CN 10- Vagus
CN 11- Accessory

Lesions from the cerebral hemispheres are knows as _____

UMN lesions

The control circuits do NOT have direct contact with the ____

LMN

What is the function of the basal ganglia control circuit for speech?

regulation of slower components of speech for postural support, such as in articulation.
regulates muscle tone, movements associated with goal directed activities, such as arm swing during walking, automatic activities, such as chewing and walking, postural adjustments, learning new movements

What are the effects of damage to the basal ganglia control circuits?

Hypokinesia- disease of substantia nigra - inefficient dopamine
Rigidity
Affects segmental-phonemic linguistic speech
Hyperkinesia- excessive dopamine - involuntary movement, excessive unpredictable tone

What is the function of the cerebellar control circuit?

includes cerebellum structures
flocculonodular lobe-balance and orientation of head, regulates posture, gait, and trucal tone
Posterior lobe- coordinating skilled sequenced voluntary muscle activity

What is the function affecting speech of the cerebellar control circuit?

programming and coordinating more rapid speech movements
interprets feedback from speech muscles, tendons and joints to smooth speech production

What does damage to the the cerebellar control circuit cause?

depends on lobe that is effected
flocculonodular lobe-inability to stand or sit, swaying or falling, disturbances in gait, nystagmus
anterior lobe-gait ataxia
posterior lobe- limb ataxia, hypotonia, intention tremor, incoordination

What is the role of the basal ganglia and cerebellar control circuits?

speech programming and control

What is the function of corticobulbar pathway?

Involved in control of facial and jaw musculature, swallowing and tongue movements.
supplies CRANIAL LMNs
No major crossing
UMNs cross at the level of CNs they supply

What is the function of corticospinal pathway?

fine voluntary motor control of the limbs.
controls voluntary body posture adjustments.

What structures are in the extrapyramidal system?

cerebral cortex, Basal ganglia, thalamus, cerebellum, brainstem reticular formation, red nucleus, vestibular nuclei

What is the multi-synapsing system?

Extrapyramidal system

What is AKA final common pathway?

LMNs

What motor neurons innervate voluntary muscles?

LMNs

Which of the following is associated with unilateral damage to the speech mechanism?

unilateral motor neuron damage
peripheral damage

Which of the systems is responsible for skilled movement?

pyramidal

Where does the corticospinal tract cross over?

decussation pyramids

What tract has no major crossing? Where do the UMN's of this tract cross?

corticobulbar tract
at the level of the cranial nerve

Please allow access to your computer’s microphone to use Voice Recording.

Having trouble? Click here for help.

We can’t access your microphone!

Click the icon above to update your browser permissions above and try again

Example:

Reload the page to try again!

Reload

Press Cmd-0 to reset your zoom

Press Ctrl-0 to reset your zoom

It looks like your browser might be zoomed in or out. Your browser needs to be zoomed to a normal size to record audio.

Please upgrade Flash or install Chrome
to use Voice Recording.

For more help, see our troubleshooting page.

Your microphone is muted

For help fixing this issue, see this FAQ.

Star this term

You can study starred terms together

NEW! Voice Recording

Create Set