Text reads: The Mysteries of Life with Tim and Moby

Tim is in his bed, asleep on his back. Moby sneaks up to him. Moby is holding a feather. He tickles Tim's nose with the feather. Tim talks in his sleep.

TIM: Nuh. Um... hello, Rita.

Tim sniffs. Moby jams the feather up Tim's nose. Tim abruptly awakens.

TIM: Argh! What are you doing?

Tim reads from a typed letter.

TIM: Dear Tim and Moby, what are dreams? How does your brain make them? From, Elizabeth. Cool. Dreams are one of my favorite topics.

MOBY: Beep.

Moby covers his mouth and laughs.

TIM: What?

There is an awkward pause.

TIM: Um, anyway... the average person dreams about two hours a night. That's six years over a lifetime.

An animation shows a man with a beard, wearing a suit, sleeping against a tree. Calendar pages flutter by, illustrating the passage of time, as the man's beard grows longer and his beard and hair turn gray.

TIM: But dreaming is still a big mystery. Scientists still don't know for sure how the brain makes dreams, what they are, or whether they have any purpose or meaning at all.

MOBY: Beep.

TIM: No, not because scientists are dumb-dumbs. The technology for studying the dreaming brain has only been around for a few decades, and it still doesn't give us anything close to the whole story.

An animation shows a scientist studying the brain activity of a sleeping person.

TIM: In fact, it was only in nineteen fifty-three that REM, or Rapid Eye Movement sleep, was discovered.

Text reads: REM, Rapid Eye Movement.

MOBY: Beep.

TIM: REM is a type of sleep that happens a few times during the night. Just like its name sounds, your eyes kind of jump around a lot under your eyelids.

An animation shows Tim asleep on his back. His eyes are moving beneath his closed eyelids.

TIM: Each REM period lasts between ten minutes and an hour. It's during these cycles that you experience most of your dreams. I don't have to tell you that dreams are, well, they're strange. They combine images, sensations, people, and storylines that don't always make a whole lot of sense.

An animation shows Tim's dreams. The hair of his disconnected head is on fire. Then his head joins his headless body and he stands next to a bride whose face is covered.

TIM: They also tend to arouse strong emotions.

Tim lifts the veil from his bride's face. The face is that of Abraham Lincoln. Lincoln smiles. Tim awakens abruptly.

TIM: Argh!

MOBY: Beep.

TIM: Well, we still don't know what our dreams mean, if anything. People have been wondering that same thing for pretty much all of recorded history. Some of the earliest books in existence are dream interpretation guides.

An image shows a broken part of an ancient clay tablet.

TIM: According to many ancient cultures, the dream world was an actual place our spirits travel to when we go to sleep.

An image shows an ancient drawing of a man's spirit leaving his body during sleep.

TIM: It was commonly believed that dreams are omens, messages about future events.

An image shows an Egyptian pharaoh dreaming about a herd of cows.

TIM: It really wasn't until the twentieth century that serious scientific attention was given to the subject.

MOBY: Beep.

TIM: Well, it all started with the 1899 publication of The Interpretation of Dreams, by Austrian psychiatrist Sigmund Freud. The father of psychoanalysis, Freud, called dreams the royal road to the unconscious.

An image shows a copy of the book Tim mentions alongside an image of Sigmund Freud.

TIM: He believed that dreams are a form of wish fulfillment, representing desires that we hide even from ourselves.

An animation shows Moby lying on a couch in Sigmund Freud's office. Moby imagines himself in control of the world. Freud looks uneasy.

TIM: Freud's influence, along with that of his student, Carl Jung, dominated the field of dream research for decades.

An image shows Carl Jung.

TIM: Many great thinkers throughout history claim to have gone to bed with a problem and woken up with a solution.

An animation shows a writer deep in thought. A lightbulb appears over his head.

TIM: To this day, lots of experts still agree that dreams have a psychological origin. But according to a growing number of researchers, our dreams may not mean anything at all. One such theory, called the activation-synthesis theory, says our dreams are created by random electrical signals pulsing through our brains.

An image shows a human brain. An animation shows a close-up of human brain neurons with electricity moving through them.

TIM: The theory also holds that dreams have no plot. Instead our minds create a storyline to make sense of all the random images.

An animation shows a dream world, where there is a full moon, fish swim through the air, a toaster grows wings and flies, the Eiffel Tower is near the Hollywood sign, and a man with a panda's head holds a bunch of balloons.

TIM: Still other research suggests that dreams may serve an important physical function in the brain. Like Francis Crick, one of the guys who discovered DNA's structure, thought that dreams are a way for the brain to clean out unnecessary memories that would otherwise overload our neural pathways.

An animation shows a computer's dialogue box. Text at the top of the box reads: Cleaning Unnecessary Memories. Images of individual documents move from an icon of a brain to an icon of a trash can.

TIM: The real answer may be something in between all these theories. Even if dreams are random signals, they could also serve physical and psychological functions.

MOBY: Beep.

TIM: Well, you don't have a brain, technically, so you don't dream.

Moby looks sad.

TIM: Sorry.

The scene changes. Moby sits with his eyes closed. A charger is plugged into his head. He dreams of a robot sheep with glowing red eyes. He smiles in his sleep.

Community content is available under CC-BY-SA unless otherwise noted.