Question

Karan was standing on a high stool and cleaning the ceiling fan.

He suddenly loses balance and sustains a head injury. An examination reveals that his pupils have lost the capacity to constrict in bright light. Which structure has been damaged?

Options

• Suspensory ligaments

• Medulla oblongata

• Eye lens

• Eye lid

Answer 1

Medulla oblongata

Explanation:

Pupil constriction in bright light is a reflex controlled by the brainstem. A head injury affecting this pathway stops the pupils from constricting. Only the medulla oblongata is part of the brainstem.