Have you ever wondered if your cat is chasing after a mouse or if your dog is playing fetch while they are sleeping? One philosopher and professor at San Francisco State University has wondered precisely that. David M. Peña-Guzmán is the author of When Animals Dream: The Hidden World of Animal Consciousness. According to Peña-Guzmán, the answer is yes - that animals do dream while they sleep. Here's what he found.
While there is no way of knowing if your pet is counting sheep since they cannot exactly tell us what they dreamed about, Peña-Guzmán believes there is enough evidence to claim that animals have dreams. “This is something I saw in various studies: the physiological markers of dreaming,” Peña-Guzmán said when speaking to VICE. He continued to explain that the heart rate and respiration usually go down when falling asleep, but there was a critical window when everything went the other way. “This is also the same period when animals start making, in the case of mammals, in particular, facial grimaces and signs of distress that indicate that they are bothered,” Peña-Guzmán stated. He believes that this is when dreaming occurs.
In the 1960s, Michel Jouvet studied domestic cats’ behavior as they slept and discovered dreaming within cats. During REM sleep, when brain activity is increased, and dreams occur in humans, human muscles are not moving. Jouvet realized that there is something in cats’ brains that help them regulate their REM sleep and keeps them paralyzed in sleep. When Jouvet removed that structure, also called the pons, the cats began to move in their sleep as if they were awake. They would hunt, jump, and groom themselves. Peña-Guzmán said about the study, “The cats performed behaviors that are very easy to interpret as mapping onto a waking experience.”
Clearly, there is still more to learn about animals and what happens when they are catching some z's. But until there is more to report, sweet dreams! And, of course, stay tuned.