Image Based Question – 74219

Which of the following muscle is supplied by the nucleus present beneath the area marked by the arrow below? Mark the image

A. Risorius

B. Lateral rectus

C. Inferior oblique

D. Medial pterygoid

Correct Answer » B Explanation

Ans: B. Lateral rectus

 (Ref: Gray’s 41/e p275. 40/e p240)

• The marked structure is facial colliculus.
• Abducent nerve nucleus is located deep to facial colliculus.
• Supplies lateral rectus.

Facial colliculus:

• Situated in pons.
• Overlies abducent nucleus.
• Facial nerve originates from its nucleus & goes around abducent nerve.
• This is called as neurobiotaxis.
• Formed by axons of facial nerve (not by abducens nucleus deep to it).