upper and lower motor neurons

Question 1

upper motor neuron

Answer 1

voluntary movements

Question 2

lower motor neuron

Answer 2

involved in all movements (voluntary and reflexive)

cell bodies in spinal cord

Question 3

motor homunculus

Answer 3

1. There are 3 major representations in M1 –face; arms; legs.
2. Adjacent muscle groups are targeted by adjacent regions of cortex
3. Surface area in cortex is proportional to level of fine muscular control

Question 4

lateral pathways

Answer 4

voluntary movements

direct cortical control-descend directly from cortex

Question 5

ventromedial pathways

Answer 5

posture and locomotion

brain stem control

Question 6

lateral corticospinal tract

-origin

Answer 6

motor cortex

Question 7

lateral corticospinal tract

-decussation location

Answer 7

medullary pyraminds- junction of medulla and spinal cord

Question 8

lateral corticospinal tract

-termination

Answer 8

dorsolateral region of ventral horns

Question 9

lateral corticospinal tract

-functional control

Answer 9

distal muscles (eg fine motor control of fingers and hand)

Question 10

lower motor neurons lesions symptoms

Answer 10

flaccid paralysis (-plegia)

paresis (weakness/incomplete paralysis)

muscle atrophy

areflexia

Question 11

upper motor neuron lesions symptoms

Answer 11

first day - flaccidity, hypotonia, areflexia

long term symptoms-
loss of find/fractionated movements
spasticitiy (hyperflexia and hypertonia)
babinski sign