The data from your right eye goes to your left brain and the data from your left eye goes to your right brain.
Actually, that's not quite correct. The data from your right
field of vision goes through
both eyes to your left brain. And vice versa with your left side. But this is just a minor quibble.
You literally see the same event twice, but these two times where you see it twice are so close together that you can't consciously say to yourself "ok, this is the first time i've seen this, 1, 2, 3, ok, this is the second time i've seen this..."
I think Jon's misunderstanding comes from a misunderstanding of memory. There are many types of memory. Something that happened half a second ago has not yet been (and may never be) placed in long term memory, which is the sort of memory Jon is thinking about (more specifically, explicit long term memory). Sensory memory is a kind of memory that lasts for less than a second, and remembers what you've seen perfectly. From what I gather from your explanation of deja vu, the two sensory memories (left brain and right brain) don't quite match up.
I hope this clarified some things.
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