Final answer:
The correct statements about the papillary light reaction following left optic nerve injury are that both pupils do not respond to light shined in the left eye, but both contract when light is shined in the right eye.
Step-by-step explanation:
The correct statements about papillary light reaction in the complete injury of the left optic nerve are:
- Both pupils do not respond when illuminated by flashlight to the left eye.
- Both pupils contract when illuminated by a flashlight to the right eye.
The pupillary light reflex involves sensory input through the optic nerve and motor response through the oculomotor nerve to the ciliary ganglion, projecting to the circular fibers of the iris. When the left optic nerve is damaged, shining light in the left eye will not elicit any pupillary response because the afferent pathway is interrupted. However, when light is shined into the right eye, the intact afferent pathway through the right optic nerve and the efferent pathways will cause both pupils to contract.