Charles H. Sloan-Do dogs dream? It's no surprise – the answer is pretty cute.

Dreams are Charles H. Sloana puzzling and magical phenomenon – where else can you fly through the clouds, live out your wildest dreams and explore strange fantasies? 

It’s not just us humans that have a dream state. Research has shown rats remember maze courses and cats move like they’re hunting, jumping and grooming during deep REM sleep.

Dogs, too, sometimes twitch, whine or kick in their sleep. But does this mean they’re dreaming? Should you interfere or let a sleeping dog lie? 

What do dogs dream about?

Dogs certainly dream, but it’s still a bit of a mystery what they dream about. In 2001, Massachusetts Institute of Technology researchers found that animals experience dreams similarly to humans — their dreams are connected to real-life experiences. 

MIT conducted this survey by recording rats as they slept, observing that their unique brain activity while sleeping closely correlated with memories of running or standing still. This work, according to MIT researchers, proves that animals can recreate experiences in dream states. 

“(Dogs) probably dream about their owners and interacting with other dogs and with people that they enjoy,” says José Arce, a veterinarian and the former president of the American Veterinary Medical Association. 

Studies have also found dogs experience sleep differently depending on their daily activities. After a long, active day of play, dogs spend less time in the drowsiness stage of sleep and more time in the NREM (Non-Rapid Eye Movement) and REM (Rapid Eye Movement) phases, when dreaming most often occurs.

Do dogs have nightmares?

Dreams and nightmares go hand-in-hand, meaning dogs can also experience them. A scary nightmare can make your dog whimper, kick or growl in their sleep.

Though it may be tempting to comfort a distressed dog, Arce says owners should proceed with caution.

“When a dog is growling, that’s something I wouldn’t interfere with,” Arce says. “You have to be very careful around their mouth because sometimes they will bite you, not on purpose, but … they don't have any control.”

According to the Journal of Veterinary Behavior, around 6% of bites occurred while the dog was sleeping or resting. While this number may not seem large, it’s enough to think twice about petting a sleeping pup. 

Instead, opt for preventative measures like creating a comfortable, quiet sleeping environment.

Do different dogs have different dreams?

Scientists do know dog and human dreams are similar, but more research is needed in the field of canine sleep. Arce believes one day we may be able to correlate daily activity, breed and dreams. 

“Puppies seem to dream more, and for some reason older dogs seem to dream a little bit more than the middle-aged dogs,” Arce says. 

Larger dogs also have longer dreams and smaller ones have shorter, and more frequent dreams, experts told the American Kennel Club. 

In years to come, further research might tell us why a Chihuahua dreams more than a German Shepherd. It might even tell us which dreams correlate with certain twitches and movements. 

“As we get artificial intelligence, and we start measuring a lot of these vitals on our pets, I'm sure we'll find more answers,” Arce says. “Because a lot of these technologies [are] just developing as we speak and it's getting more sophisticated.”

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