Anil Seth

And then finally, and a little bit more at the extreme end of all this,

Understanding perception as this act of construction, this top-down reaching out from the brain to the world, gives us a new way to think about a variety of mental illnesses and psychiatric disorders that are usually expressed by people having unusual experiences of the world or of the self.

And the more we can understand the mechanisms by which this is happening, the more promise there is to develop new approaches to diagnosis and treatment.

Well, it's just gone, isn't it?

This is, for me, a remarkable thing.

And actually, sleep is very different from anesthesia.

This is something that's always struck me, that when you fall asleep,

you might lose consciousness completely and then start dreaming or something.

But when you wake up, you know that some amount of time has gone by.

I mean, you might be a bit confused about exactly how much time, whether it's five or six hours, but you roughly know that some amount of time has gone by.

But under general anesthesia, if it's general anesthesia that completely knocks you out,

You are gone and then you are back.

And it seems like no time has passed at all.

And there's no indication of whether it was five minutes or five hours or 50 years that you were gone from.

You were simply not there in the same way that you weren't there before you were born and that you won't be there after you die.

And for me, this is a really deeply personal lesson that consciousness is

can go away.

The natural state of the brain is to generate no experience whatsoever.

The amazing thing, of course, about anesthesia is that you turn a person into an object, but then the object gets returned back into a person afterwards.

Yeah, this is a very common thing that people will say, and I think there is some truth to it, but it depends on the timescale, right?