Rhonda: Why do you sometimes not remember your dreams and sometimes you do remember your dreams? Do you have any idea?

Matt: Yeah. So some of it seems to be about, if you wake up out of that dream sleep period and then you go back into sleep, the awakening can sometimes help you commit that experience to memory.

Rhonda: Oh, okay.

Matt: But there are people who say that I never remember my dreams, you know. We can bring those people into my sleep center, and we can, you know, wake them up in the middle of dream sleep, and they'll say, "It's remarkable. For the first time, I was dreaming." And the answer is no. It's not the first time that you are dreaming. It's just the first time that you've actually remembered a dream, because it's the first time you've typically woken up.

Rhonda: Okay. My mother-in-law, you know, claims that she doesn't dream. And, of course, I'm like, "No, you have to dream."

Matt: Yeah.

Rhonda: That must be...

Matt: There are a selection of patients that have a lesion in a part of the prefrontal cortex, in their white matter, which are these big sort of informational fiber tracts that communicate impulses. If you get a lesion deep down there, we do seem to genuinely see a cessation of dreaming in those patients.

By the way, I would...I didn't even feel confident to write this in the book, and it's still a theory that I've never really heard in public, but go with me on this. Which is, I think that we may actually remember all of our dreams, or it's possible that there's a tenable theory. The problem is we don't have access to those dreams. Those dreams are memorized, and they are available. They're just not accessible. I think what happens as we wake up is that we lose the IP address to those memories. And the reason I believe this to be potentially true is have you ever had the experience where you wake up and you think, I was dreaming, and I know I was dreaming. And you try as hard as you can. The harder you try, the...

Rhonda: Yeah.

Matt: ...worse the memory-recall goes? And then you think, forget it. Two days later, you're walking along, and you see a street sign, and all of a sudden, it triggers the unlocking of that dream memory. You think, oh, that's what the dream was about.

As a neuroscientist, that tells me that the memory was present. The memory was available. The problem was accessibility. You couldn't gain recall access. So the information is there. It's just not accessible. If that's true...

Rhonda: It's happened to me just even after I've, you know, when I go to bed. You know, later that night, I hit the pillow, and all of a sudden, I remember the dream right as I'm hitting the pillow.

Matt: Right.

Rhonda: That's happened to me more than once. But you're right.

Matt: Right. It sort of tells you that there is...it's almost a scary prospect, which is that maybe every single one of our dreams throughout life are stored and are present and determine our behavior to some degree, because we know that there is an enormous amount of information that changes our behavior or decisions that goes on below the radar of consciousness, implicit memory. That could be true for dreaming, too.

And I think I've got an experiment that we may be able to design to actually get at this. And if that's true, it should, hopefully, radically change our view of dreaming, that dreams are ephemeral, that they dissolve quickly, they're forgotten, and they don't influence us as human species.

Rhonda: That would be pretty groundbreaking.

Matt: Yeah...