<prompt> Afferent pathway for pupillary light reflex is: September 2007Optic nerveOculomotor nerveTrigeminal nerveCiliary nerve  <response>: Ans. A: Optic nerve Under normal conditions, the pupils of both eyes respond identically to a light stimulus, regardless of which eye is being stimulated. Light entering one eye produces a constriction of the pupil of that eye the direct response, as well as a constriction of the pupil of the unstimulated eye the consensual response. Comparing these two responses in both eyes is helpful in locating a lesion Normally, both pupils should constrict with light shone into either eye alone. On testing each reflex for each eye, several patterns are possible. Optic nerve damage on one side: - The ipsilateral direct reflex is lost Example: when the left eye is stimulated, neither pupil constricts, as no signals reach the brain from the left eye due to its damaged optic nerve 