A lion is chasing me. I stumble through tall grass, desperate to escape. The lion comes so close I can hear it breathing. Then suddenly I’m safe in bed, wide awake and puzzled. What woke me?
My furry friend Slade did. He is lying beside me, on his back with his feet in the air, and all four feet are kicking. His tail is swishing, too. And he’s talking in his sleep: squeaky mews like his waking voice, but with the volume turned down.
Oh, I think, Slade is dreaming, too.
Am I right? Probably, but because pets can’t tell us their dreams, no human can be 100 percent sure.
I’m not alone in my strong hunch that cats and dogs dream. Friends tell me their pets must dream: They make running motions, and the dogs even bark in their sleep. Way back in 44 B.C., the Roman philosopher Lucretius watched a dog’s feet jerk during sleep and decided the animal was chasing an imaginary rabbit. In our own time, neuroscientist J. Allan Hobson has stated in The Dreaming Brain, “It is embarrassing to admit that … any one of us could have discovered REM sleep simply by watching the twitching paws and eyes of our pet dogs and cats.”
Everyone needs REM sleep
REM (rapid eye movement) sleep is the stage of slumber in which humans dream. It is also called paradoxical sleep because our muscles are relaxed, yet our brains are very active. (The relaxed muscles, luckily, keep us from acting out our dreams.) Our eyes dart around as if we’re watching something, the visual cortex of the brain is activated, and vivid pictures much like movies are generated. Other mammals show the same kind of brain activity, so maybe they, too, see moving pictures in their dreams.
Both humans and other mammals alternate between light (dreamless) sleep and deep (REM) sleep. If we humans don’t get enough dreaming time, we snap at our friends and have trouble concentrating. Animals also need their REM sleep. According to Joan Spielholz, a research associate at the Cornell College of Veterinary Medicine, “Cats need much more essential deep sleep than a mere catnap provides. Like humans, if they are deprived of deep sleep, they get irritable.”
Doesn’t all this evidence prove that, as many pet owners suspect, animals dream? Speaking as a scientist, Spielholz admits, “Do we know for sure? Well, no. We can only make an educated guess that feline deep-phase sleep is analogous to the human counterpart.”
Speaking as an owner
But Spielholz is also a devoted pet owner, and in that role she sounds far less cautious: “As a longtime observer of cats, I can state with authority that I have witnessed them dreaming! Sometimes I even try to guess what they might be dreaming about. The tail thrashes, the whiskers twitch. The ears move forward, and the paw swipes. Is that a contented smile I’m looking at? It appears to be a pleasant experience!”
Maybe, while I was dreaming of running from a lion, Slade was dreaming of being a lion, stalking his prey through the tall grass. If so, it was probably a pleasant experience for him—I just hope he didn’t cast me as the prey.
Until we learn our pets’ language (or, more likely, they learn ours: Slade and his sister Abby already understand everything I say, except the word “no”), we won’t be positive that they dream at all, let alone what about. But when Slade kicks and mews in his sleep, I’m convinced he’s in dreamland. I hope all his dreams are pleasant, and he is never the one being chased by a lion.