Dr. Matt Walker

I want to let go of the emotion.

I want to sleep to remember, and I want to sleep to forget.

And I'll come on to why I think that's relevant to PTSD when we perhaps speak about that condition, and it's very, very relevant.

But coming back to REM sleep,

We looked back in the literature to see if we could find signs that REM sleep had this relationship with even just your basic emotional reactivity.

And there was some wonderful work by a gentleman that you will know from Stanford, probably one of the founding fathers of modern day sleep research, a gentleman called William Dement.

He was not, but he was well up there in terms of understanding both sort of what its term was and also what its function was.

He, legend as he was, very early on, this was probably in the 60s, he would take individuals because we didn't really have the first published report of these two types of sleep, of REM and non-REM, until they collected the data or found the data in 1953.

It was published in 1954.

So in other words, we discovered...

that even up to then, prior to then, we just thought sleep was sleep.

We didn't have any knowledge that these different stages.

So in the same year that Francis Crick unveiled this incredible helical structure that was called a DNA strand, we also discovered the different stages of sleep.

But in the 60s then, William Dement, knowing that there were these two types of sleep and knowing that there was something that was going on with REM sleep where people were dreaming and he would be waking people up from these different stages and found that it's far more likely for people to report a dream.

He wondered what the consequence would be if you selectively deprive people of this stage of sleep, of dream sleep.

So he brought individuals into his laboratory.

And every time they would go into REM sleep, they would go into the room, they would wake them up, have them do some mathematical problems for two or three minutes, and then put them back asleep.

And they go back into non-REM.

And then as soon as they went back into REM...

They would wake them up again.