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Discussion Starter · #1 ·
The direct and the consensual pupillary light reflexes tests the integrity of which of the following parts of the nervous system?

A- Midbrain
B- Superior Cerival Ganglion
C- Pons
D- Visual cortex
E- Medulla
 

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Discussion Starter · #3 ·
is it visual cortex = D
Again, I disagree with you :)
The pupillary light reflexes do not reach the cerebral cortex. They relay in the oculomotor and edenger westphal nuclei in the midbrain and come back to the eyes.
The correct answer is midbrain.
Do not be fooled by the fact that the afferent limb is served by the optic nerve, because even though the optic nerve does go all the way to the cerebral cortex but as far as the pupillary reflexes are concerned the signal take a U turn in the midbrain.
 

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Again, I disagree with you :)
The pupillary light reflexes do not reach the cerebral cortex. They relay in the oculomotor and edenger westphal nuclei in the midbrain and come back to the eyes.
The correct answer is midbrain.
Do not be fooled by the fact that the afferent limb is served by the optic nerve, because even though the optic nerve does go all the way to the cerebral cortex but as far as the pupillary reflexes are concerned the signal take a U turn in the midbrain.
i forgot where the edenger westphal nuclei lied. :)
 
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