Final Exam: UMN/LMN Flashcards
UMN and LMN are afferent or efferent
efferent (descending)
UMN or LMN? cell bodies in CNS
Both
UMN: cortex and brainstem
LMN: spinal cord
UMN or LMN? terminate on lower moter neurons in the CNS
UMN
UMN or LMN? innervate skeletal m.
LMN
UMN or LMN? information from brain to spinal cord segment
UMN
UMN or LMN? information from spinal cord segment or motor unit
LMN
UMNs/LMNs function to initiate and direct voluntary activity of m. and maintain muscle tone for support and regulation of posture/balance
UMNs
Axons of UMN cell bodies travel down the SC via either the _____ motor system or the _____ motor system
Dorsolateral or ventromedial
LMN cell bodies are found in the dorsal/ventral horn of the SC
Ventral
point-for-point correspondence of an area of the body to a specific point in the CNS
somatotopy
What UMNs are located in the dorsolateral area of the SC?
distal m.: fine motor segments and flexors
What UMNs are located in the ventromedial SC?
Proximal m.: whole limb movement
primarily extensors
Which part of the SC houses m. used for posture and balance?
Ventromedial
What happens if there is damage to the dorsolateral motor systems?
dec. or absent voluntary movements of the fine fotor systems
What happens if there is damage to the ventromedial motor systems?
dec. or absent voluntary movements of the whole limb
What happens if the afferent sensory pathways are damaged?
prevents sensory info from reaching the brain
dec. or absence of proprioception, nociception, and tactile sensation
What is housed in the white matter of the SC?
axons
What is housed in the grey matter of the SC?
cell bodies
Which horn of the SC recieves afferent info and relays to interneruons
Dorsal horn
what is in the intermediate zone of the SC
interneurons
Which horn of the SC houses cell bodies of efferent motor neurons
ventral
Where is the lateral horn of the SC?
only on thoracic and lumbar spines
what is contained in the lateral horn of the sc?
cell bodies of presynaptic sympathetic neurons
T/F. Transverse damage to the spine causes both UMN and LMN damage
t
You will see UMN signs cranial/At/caudal to the spinal lesion
Caudal
You will see LMN signs _cranial/at/caudal to the spinal lesion.
At
What are the 4 LMN signs?
- paresis or paralysis
- Dec/ absent m. tone
- Dec/absent reflexes
- Rapid onset m. atrophy
What are 4 UMN signs?
- Paresis or paralysis
- Normal to inc. m. tone/clonus
- Normal to inc. spinal reflexes
- slow m. atrophy
somatic innervationof the bladder?
pudendal n.
urethralis m. voluntary control of micturition
PSNS innervation of the bladder
pelvic n,
smooth m. contraction of bladder
SNS innervation of the bladder
Hypogastric
inhibitor action of detrussor m.
UMN Bladder signs
No voluntary micturition
severe bladder distension
inconsistent urine leakage
resistance to manual expression
LMN bladder signs
Continuous leakage, dribbling
no tone to urethralis
evacuation of bladder is easy
What is schiff-sherrington syndrome?
severe damage to T3-L3
inc. in thoracic limb extensor tone (rigid extension of limb)
