Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Gross Anatomy II > Reflex and UMN/LMN > Flashcards

Reflex and UMN/LMN Flashcards

1
Q

Neurons whose cell bodies are located in the brain and various brain stem nuceli?

A

Upper motor neurons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Somatic neurons whose cell bodies are located in the spinal cord and specific brain nuclei?

A

Lower motor neuron

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

The __________ pathway consists of UMN axons that descend into the spinal cord and synapse directly onto LMN

A

Pyramidal (i.e. Corticospinal)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

The pyramidal pathway regulates?

A

Fine tuned/Skilled movements

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

The ____________ pathway consists of UMN that synapse onto interneurons in brain nuclei before continuing to LMN

A

Extrapyramidal (corticorubrospinal)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

The extrapyramidal pathway controls what movements?

A

Muscle tone and initiation of whole limb movements

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What type of neurons are involved in the spinal reflex?

A

LMN

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

A spinal reflex can occur without _________ but may result in a exaggerated/abnormal response

A

UMN

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

The organization of the spinal cord in a point- for point correspondence with a specific body part is called?

A

Somatotopy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

UMN traveling in the _______________ regulate LMN cell bodies in the more lateral aspect of the ventral horn, which corresponds with what part of the the limb?

A

Dorsolateral motor system; distal musculature (fine tuned movements)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

UMN traveling in the ____________ regulate LMN cell bodies in the medial aspect of the ventral horn. What aspect of the limb does this control?

A

Ventromedial motor system; proximal musculature (whole limb movement, posture and balance)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Damage to the dorsolateral motor system will have what affect on voluntary movement?

A

Paretic or paralyzed movement to the fine mortar systems (flexor systems) caudal to the sight of damage

Eg.
Damage at T13 -> decreased/absent fined tuned movements of the distal pelvic limb

Damage at C3 -> decreased/absent fined tuned movements of the distal aspect of the forelimb and hindlimb

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Damage to the ventromedial motor system will have what affect on voluntary movements?

A

Paretic or paralyzed movement of the whole limb (mostly extensor) caudal to site of damage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Damage to afferent sensory pathways in the spinal cord causes?

A

Loss of sensory information reaching the brain

Loss occurs in increasing predictable and increasing severity by loss of : 
General proprioception
Motor control 
Superficial pain 
Deep pain
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

UMN signs are observed ________ to a spinal lesion or injury

A

Caudal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

LMN signs are seen _________ of the lesion or injury

A

At the site

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

If you pinch the dorsal aspect of an animals forelimb and do not observe a reflex, this is a _________ sign indicating damage to what portion of the spinal cord?

A

LMN; C6-T2 (cervicothoracic)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

If you pinch the dorsal aspect of an animals hindlimb and do not observe a reflex, this is a _________ sign indicating damage to what portion of the spinal cord?

A

LMN; L4-S2 (lumborosacral plexus)

19
Q

In a dog you observe a normal reflex to pinching of the dorsal forelimb and the dog turns to look at you. When pinching the hindlimb you observe a reflex but the dog doesn’t turn around or growl. With respect to the hind limb, you have _________ signs. Where is the lesion?

A

UMN; between T3-L3

20
Q

What nerves are involved in the micturition control

A

Pudendal - somatic

Pelvic - PSNS

Hypogastric -SNS

21
Q

Filling of the bladder activates stretch receptors that travel afferently in the ___________ nerve

A

Pelvic

22
Q

What reflex pathway allows the filling of the bladder?

A

Filling activate stretch receptors -> pelvic nerve (afferent) -> ascends in the spinal cord -> synapse to SNS -> hypogastric nerve => inhibit detrussor m and stimulates IUS

23
Q

When the bladder is full and urine escapes through the IUS what reflex pathway is initiated?

A

Stretch receptor in urethra -> visceral afferents in pelvic nerve -> synapse to somatic pudendal nerve -> reflexive contraction of EUS

This is so you dont pee in inappropriate places

24
Q

A lesion to S1-S3 would cause _________ bladder signs. Clinically you see continuous leakage. What pathways are disrupted to cause this?

A

LMN

Pelvic afferent to the SNS hypogastric is blocked -> lack of tone to detrussor m. and IUS

Somatic efferent -> no tone to EUS

Continuous leakage

25
Q

Describe an UMN bladder lesion

A

UMN: Reflex pathway still intact -> when urine leaks into urethra -> pudendal nerve contracts EUS

Unable to perceive full bladder and consciously relax EUS to urinate –> severe bladder distention and leakage only when pressure of bladder overcomes the contracted EUS

26
Q

What is the difference between reflex and and reaction?

A

Reflex is unconscious integration at the level of the spinal cord

Response is conscious integration occurring in the brain

27
Q

What are the components of a intact spinal reflex?

A 
Sensory receptor
Afferent neuron 
Interneuron (within spinal cord) 
Efferent neuron (motor or autonomic) 
Effector organ
28
Q

True/False: you can have both somatic and visceral reflexes

A

True

29
Q

A reflex with only one synapse between the afferent and efferent neurons

A

Monosynaptic

30
Q

A reflex with multiple synapses

A

Polysynaptic

31
Q

A reflex arc than spans several spinal cord segments?

A

Intersegmental

32
Q

A reflex arc that is contained within one or two spinal cord segments

A

Segmental

33
Q

What types of receptors are important in reflexes that maintain balance and muscle tone?

A

Proprioceptors (muscle spindles/ golgi tendons/ and joint capsules)

34
Q

What segment of the spinal cord does the nerves for the thoracic limb originate?

A

C6-T2

35
Q

What segment of the spinal cord does the nerves supplying the pelvic limb originate ?

A

L4-S2

36
Q

What is the myotactic reflex?

A

Induce stretch in receptors in tendons
-> muscle will contract in response

Eg patellar reflex

37
Q

What is clonus of a reflex? When can this occur?

A

Myotactic reflex is initiated -> muscle contracts in response to stretch of tendon.

When muscle relaxes and the tendon is stretched again the reflex is initiated again. Cloning of the reflex

UMN lesion- unable to regulate the reflex response

38
Q

The panniculus reflex is useful for testing spinal cord segments ______________

A

C8-T1

39
Q

What is involved in the panniculus reflex?

A

Sensory from the skin of the trunk (afferent )
C8-T1
Lateral thoracic nerve motor innervation cutaneous trunci muscle (motor)

40
Q

What reflex is elicited in response to a painful stimulus?

A

Withdrawal (flexor) reflex

41
Q

During a withdrawal reflex of a limb when standing, requires what type of additional reflex to maintain balance?

A

Crossed-extensor reflex (polysynaptic reflex)

42
Q

A withdrawal reflex initiated in a recumbent animal should not display a __________________, in a healthy animal

A

Crossed-extensor reflex

UMN inhibit this reflex

43
Q

If a crossed extensor reflex occurs while an animal is recumbent, what defect is present

A

Defect in spinal cord cranial to reflex arc.

Afferent info regarding body position is not reaching the brain

Efferent UMNs are not reaching LMNs to regulate the reflex

44
Q

The perineal reflex tests what spinal segments

A

S1-S3 (pudendal nerve)

Gross Anatomy II (11 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions