Your brain is two brains, two hemispheres, each doing half the work of being you.

Half your vision goes to each and half your movement directed by each.

Right controls left and left controls right.

Your two brains coordinate through a wire of nerves, but this wire can be cut and was for a time used as an epilepsy treatment.

After the cut, people seemed the same, though their brain was split in twain.

Except some post-split patients describe that while selecting their morning outfit with

right hand, left might come along to disagree.

Actually, left hand might quite often disagree, which these split brain patients found frustrating.

What's happening? To investigate, remember, right brain sees and controls one half while left brain controls and sees the other.

But only left brain can speak,

Hello.

Because that's where the speech center is located. Right brain without this is mute.

In normal brains, this doesn't matter because

each half communicates across the wire with the other. But split brains can't and thus you

can show just the right brain a word, ask the person what did you see and you'll hear

Nothing.

Because left speaking brain saw nothing. Meanwhile, right brain will use its hand to pick the object out of a pile hidden from

left brain.

This is deeply creepy.

Ask why are you holding the object and speaking left brain will make up a plausible sounding

but totally wrong reason.

I always wanted to learn how to solve one of these.

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