Efferent Auditory Pathway

Question 1

Which system has more fibers? Afferent or efferent?

Answer 1

Afferent.

Question 2

Why is the efferent system so complex?

Answer 2

Combines at points with the ascending system to form various feedback loops.

Question 3

What is the most studied portion of the efferent pathway?

Answer 3

Olivocochlear bundle.

Question 4

Where does the olivocochlear bundle course?

Answer 4

From the superior olivary complex in the brain stem to the base of the hair cells.

Question 5

What are the two types of neural connections in the efferent auditory pathway?

Answer 5

Ipsilateral, and contralateral.

Question 6

What are ipsilateral connections? Where do they synapse and terminate?

Answer 6

Fibers stay on same side of brainstem as the target cochlea. Synapse at the superior olivary nucleus and terminate at the afferent fibers of the inner hair cells.

Question 7

What are contralateral connections? Where do they synapse? Terminate?

Answer 7

Travel on opposite side of the brainstem from the target cochlea- fibers in these connections synapse at the superior olivary nucleus and cross the floor of brainstem to join the ipsilateral fibers in the vestibulocochlear nerve. Terminate at the outer hair cells.

Question 8

How many contralateral connections cross over and reach the cochlea from the contralateral superior olivary nucleus?

Answer 8

4/5

Question 9

Where does the efferent auditory pathway begin?

Answer 9

Auditory cortex and courses along similar route until it reaches the cochlea.