Pupillary light reflex pathway question

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str8flexed

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When light is sensed by the left eye by CNII, does it go to the ipsilateral Pre-tectal nucleus, and then innervate Edinger-Westphal nuclei bilaterally...
(this is the description UWorld gave!)

Or is light sensed by CNII, and then it stimulates BOTH pre-tectal nuclei, which then both bilaterally stimulate Edinger-Westphal nuclei....
(this is what the diagram in FA (p.400) shows!)

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Word for word from HY Neuro(p105):

"A. GANGLION CELLS OF THE RETINA, which project bilaterally to the pretectal nuclei.

B. The prectectal nucleus of the midbrain, which projects(through the posterior commissure) crossed and uncrossed fibers to the accessory occulomotor (Edinger-Westphal) nucleus."

Optic nerve fibers project from the ipsilateral nasal field to the contralateral pretectal nucleus and from the ipsilateral temporal field to the ipsilateral pretectal nucleus.

Each pretectal nucleus projects only to its ipsilateral Edinger-Westphal nucleus. However, the two pretectal nuclei communicate with eachother via the posterior commisure so you have bilateral indirect projections from the pretectal nuclei.
 
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