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you might have figured out the reason why we dream. Yes. So, it turns out if you go blind, the visual cortex at the
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back of the brain gets taken over by hearing and by touch and by other things, and it's no longer visual
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cortex. We live on a planet that rotates into darkness for half the time, the visual cortex, the visual part of your
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brain, is at a disadvantage. So, what I realized is that the purpose of dreaming
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is to defend the visual territory from takeover from the other senses. So, every 90 minutes you've got these um
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you've got this very ancient thing in your midbrain that shoots random activity into the visual system, and
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only the visual system, only this very tiny part of the visual system. Every 90 minutes you just blast random activity
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in here. The reason is you are just defending that territory against takeover. So, our colleagues at Harvard
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did an experiment where they took normally sighted people and they blindfolded them tightly for 60 minutes,
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and it turns out that 60 minutes was sufficient for the visual cortex to start responding to sound and to touch.
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You could start seeing that takeover happening after 60 minutes. Wow. This this part of the brain really needs a
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way of defending itself. Now, because the brain is a natural storyteller, if you blast random activity in there,
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it'll, you know, put that together in some sort of visual story about what's
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happening, mostly based on what connections are hot from the day, but that's why we dream. So, we we dream to
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stop the other parts of our brain overtaking the visual part of our brain, um overpowering it, and I guess
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ultimately making us go blind. Yeah, that's exactly right. If we lived on a different kind of planet that did not
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rotate into darkness, then we would we presumably wouldn't dream. Would we even
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need to close our eyes? I mean Not necessarily. Yeah. It may be that in the sleeping state, in the state of deep
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sleep, the brain is doing particular things, like taking out the trash and cleaning some things up that might be
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necessary. Who knows. But yeah, I don't think we would need to dream. We wouldn't need to blast random activity
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in there, um, you know, if if if our eyes were always open, for example, and it was
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always light out.