Dr. Matthew Walker

Now, before you reject my diagnosis of your nightly psychosis, I'll give you five good reasons.

First, when we start to dream, we see things which are not there, so we hallucinate.

Second, we believe things that could not possibly be true.

So we're delusional.

Third, we get confused about time, place, and person.

So we're suffering from disorientation.

Fourth, we have these wildly fluctuating emotions, something that psychiatrists call being affectively labile.

And then how wonderful

You woke up this morning and you forgot most, if not all of that dream experience.

So you are suffering from amnesia.

If you were to experience any one of those five symptoms while you're awake, we'd probably be seeking psychological or psychiatric treatment.

But for reasons that we still don't fully understand, that seems to be a normal biological and psychological, and in fact, and I'll describe the data, absolutely necessary life support, perhaps necessary set of experiences to go through.

So that's the peculiarity of dreaming, but how do we define it?

One of the loose definitions that we often use in sleep science is that a dream is any report of mental activity upon awakening.

So I'll come into the laboratory and I'll wake you up and I'll say, what was going through your mind?

And if you just say, nothing really.

then we note that down as no dream report.

But if you were to say, well, you know what?

I was actually just thinking about the next time you're going to come in and wake me up, then we would report that as a dream.

But that's not really what most people mean when they say, I had this strange dream.