Dr. David Eagleman

That might be necessary.

Who knows?

But yeah, I don't think we would need to dream.

We wouldn't need to blast random activity in there if our eyes were always open, for example, and it was always light out.

Are there other examples in the animal kingdom?

which support this?

Yes, thank you for asking that.

This is why this new theory about why we dream is taken off because we can make quantitative predictions across animal species.

So for example, in our last paper, we looked at 25 different species of primates, apes and monkeys.

And we looked at how plastic their brains are.

In other words, how flexible the whole circuitry was and how much they dream at night, which you can tell by looking at rapid eye movements.

You know, when you dream at night, your eyes are shooting back and forth like that.

It's called...

R-E-M, rapid eye movement sleep.

So you can measure that in other animals, their eyes moving back and forth.

So we correlated how plastic the brain is and how much dream sleep you have.

And it correlates perfectly, which is to say humans, which are the most plastic, have dream sleep all the time.

And by the way, when you're an infant, you sleep for, you have dream sleep for half of your sleep time, 50% of the time.

As you get older, you get less and less dream sleep because you just don't need it as much anymore.

But anyway, when we look across species, it correlates perfectly.