Interactive Transcript
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Let's finish our discussion of cranial nerve number two,
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the optic nerve with a couple of pearls.
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The contralateral nasal retinal projection,
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from the lateral, projecting onto the medial
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aspect of the retina.
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So lateral projecting on medial retina,
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is going to come down,
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and is going to cross over the other side.
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Same thing here,
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projects onto the medial retina,
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comes down and crosses in the optic
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chiasm to the contralateral side.
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In contrast,
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the medial field is going to project onto the
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lateral retina and it's going to
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stay ipsilateral like. So.
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Now, we also said that there are a number of
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which we'll show you in a minute.
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There is a knee or turn of the optic radiation.
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There is an occipital or occipital.
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Temporal and a temporal component of this turn,
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where it will then project onto the Cuneus or
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optic cortex. It'll happen on both sides.
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Now I'm going to scroll up a little bit
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to the level of the calcarine sulcus.
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And at this level, we've got the calcarine cortex.
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And I wanted to high light the synapse
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positions a little bit higher,
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which include the lateral geniculate nucleus,
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which is going to sit right about here on both
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sides. That's going to receive a synapse.
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The superior colliculus,
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that's going to receive a synapse.
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And now we have one final third synapse to add to
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our layering of anatomy for the visual pathway.
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And that is the pulvinar right there.
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So that concludes our discussion of the visual
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pathway. So if we put it all together,
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we've got the globes, we've got the retina,
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we've got the optic Nerve.
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We got the intracanalicular for raminal optic
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nerve. We have the prechiasmatic nerve.
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The optic chiasm a little infundibular recess
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in the middle with a pituitary stalk,
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the optic tracts moving posteriorly,
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a synapse on the superior colliculus and
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the lateral geniculate nucleus,
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a synapse on the pulvinar and
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then continuation back,
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including something known as Meyer's loop that will
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arborize onto the visual cortex in the region of
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the calcarine sulcus which we see right here.
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That concludes our discussion of the visual pathway.
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