Corticobulbar Tracts

Question 1

Rubrospinal tract

Answer 1

Motor neurons that innervate proximal limb flexor muscles. Mainly at cervical levels

Question 2

Vestibulospinal tracts

Answer 2

Lateral: Maintains posture by exciting paravertebral extensors & proximal limb extensors; orients head & body in space (found throughout the entire spinal cord)

Medial vestibulospinal tract (MLF): Positioning of neck; activates neurons of CN 11

Question 3

Tectospinal tract

Answer 3

Axial muscles of neck involved with tracking, receives visual and auditory stimuli

Question 4

Reticulospinal tract

Answer 4

Pontine reticular tract maintains posture and muscle tone by stimulating extensors

Medullary reticular tract stimulates flexors

Question 5

What is decerebrate rigidity?

Answer 5

Contraction due to supratentorial lesions that extend through tentorial notch.

No red nucleus just vestibulospinal and reticulospinal

Question 6

Decorticating rigidity

Answer 6

Supratentorial lesion with intact red nucleus plus vestibulospinal and reticulospinal

Question 7

Is there sensory loss in ALS?

Answer 7

No. It does not affect the spinothalamic tract.