DLA 18+19, Lecture 15+16

Question 1

thalamic lesion

Answer 1

Damage to third order somatosensory neurons - all modalities (touch, vibration, proprioception, pain and temperature) affected

Question 2

monosynaptic vs polysynaptic reflux

Answer 2

mono:
Afferent and efferent limb are directly connected
EX: deep tendon reflux

poly:
Afferent and efferent limb are interconnected with one or more interneurons
EX: abdominal reflux

Question 3

shoulder abduction

Answer 3

C5

Question 4

elbow flexion

Answer 4

C5/C6

reflex testing
biceps and brachioradialis

Question 5

wrist extension

Answer 5

C6/C7

Question 6

elbow extension

Answer 6

C7/C8

reflex testing
triceps

Question 7

Flinger flexion

Answer 7

C8

Question 8

finger ab-adduction

Answer 8

C8/T1

Question 9

thigh adduction

Answer 9

L3/4/5

Question 10

knee extension

Answer 10

L2-L4

knee jerk reflex

Question 11

great toe extension

Answer 11

L5/S1

plantar response

afferent = A delta and C 
efferent = alpha motor neurons (L5/S1)

Question 12

ankle plantar extension

Answer 12

S1/S2

ankle jerk reflex

Question 13

anal contraction

Answer 13

S2,3,4

Question 14

abdominal reflex

Answer 14

T8-T12

Question 15

reflex testing scale

Answer 15

0 = absent

1 = diminished

2 = brisk

3 = very brisk

4 = exaggerated

Question 16

babinski reflex

Answer 16

Dorsiflexion of the great toe while the other toes fan out (extension instead of flexion)

indicates upper motor neuron lesion

Question 17

myotatic reflex

Answer 17

a tonic contraction of muscle groups in response to a stretching force

is monosynaptic

afferent: Ia fiber (muscle spindle)
efferent: alpha motor neuron

Question 18

corticospinal pathway (two parts)

Answer 18

lateral = limbs motor

anterior = trunk motor

arise from the brainstem

Question 19

corticobulbar pathway

Answer 19

head and neck motor

arise from the brainstem

Question 20

lower motor neurons and upper motor neurons

Answer 20

Lower:
communicate directly between the CNS and somatic muscle
can arise from the spinal cord or brainstem

upper:
neurons that originate in the brain and communicate with LMN
can exert bilateral or contralateral control

Question 21

location of LMN and UMN

Answer 21

Upper:
located in the white matter
anterior, medial, and lateral funiculus

lower:
cell bodies are located within the anterior gray horn
(ventral horn)

Question 22

location of flexor/ adductor and extension/abductor neurons in the ventral horn

Answer 22

flexor and adductor neurons lie dorsal

extensor and abductor neurons lie lateral

Question 23

upper motor neuron signs

Answer 23

hyperreflexia
hypertonia 
extensor plantar 
clonus 
spastic paralysis

Question 24

Lower motor neuron signs

Answer 24

hyporeflexia 
hypotonia 
fibrillation 
flaccid paralysis 
atrophy 
fasciculations

Question 25

anterior spinal artery syndrome

Answer 25

Touch, vibration, proprioception intact bilateral loss of pain and temp below lesion extensor response bilateral paralysis