ShmoopTube

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And here's your shmoop du jour brought to you by optic nerves [eye balls dangling across each other]

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crossing each other and then double crossing each other in the summers

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biggest blockbuster eye versus eye or not. Alright here's our question where do the

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optic nerves cross each other on their way into the brain hemispheres, here are your

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potential answers.... Alright well there's pretty big spoiler built right into the

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question but the last time we spoiled something our buddies refuse to speak to [Guy holding a Harry Potter book and friends dressed in wizard hats]

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us for a month well while we're running from the angry mob let's check out a

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diagram of an eyeball alright since we're talking about optic nerves we can [diagram of inside an eye ball]

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highlight that part of the diagram and we can see, okay weak pun, well we can see

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that there's only one optic nerve per eye. So when we see a question asking about

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optic nerves emphasis on nerves.. We know that whatever we're talking about isn't [Diagram of two optic nerves attached to the eye balls]

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taking place within the eye itself with that in mind we can easily eliminate A

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the fovea we know the fovea centralis refers to a grouping of concentrated [cones appearing out of a persons eye ball]

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cones in the eye that are responsible for sharp central vision so we can see

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this one through the door and since a blind spot simply refers to an area of [a plane in a cars side mirror]

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our visual field that lacks light detecting cells on our retina and not an

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actual physiological part of the body we can eliminate this guy too. The rest of [a dog blindfolded]

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our answers do fit the not in our eyeball but definitely an actual

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physiological thing criteria, funnily enough that's the scientific name for

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these guys really you'll find out in ophthalmology school anyway we can [C and D sat in a lecture theatre]

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eliminate one of these immediately and that's because we know that Pierre Paul

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Broca was a 19th century French physician best known for his research in [Pierre examining a mans mouth]

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speech production Broca's area was aptly named because it's a part of the frontal

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lobe that is directly linked with speech production not vision that leaves us [image of Pierre's frontal lobe]

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with the lateral geniculate nucleus and the optic chiasm but only one of these

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guys is where the optic nerves cross each other on their way into the brain

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hemispheres and that would be E the optic chiasm

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who'd of thunk it right the optic chiasm right there is the space just in front [Two people dangle down a rope from hole]

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of the pituitary gland where the optic nerves cross one another through the

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brain on their way to the respective lobes and it's actually the only place [Two eyes meet at a dining table]

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any parts of each eye really meet, though we here eye-harmony is coming soon and

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there's hope for all the lonely hearts out there yet [advert for eye harmony]

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