Most dogs owners agree that their dogs dream.
When a dog is sleeping and you notice his legs twitching, hear a muffled bark or hear his teeth clicking together, and maybe even hear the thump, thump, thump of a wagging tail, it doesn’t take much imagination to think he’s dreaming about chasing a rabbit or a cat, or playing fetch with his owner.
Since your dog doesn’t wake up and tell you about the crazy dream he just had, he can’t confirm he’s dreaming, but science has done studies which seem to support this theory.
Dogs have two main sleep patterns, the same as humans—SWS (slow wave sleep) and REM (rapid eye movement). If you take the time to observe your dog as he sleeps, you can tell which pattern he is in.
Soon after your dog has dozed off, his breathing will become deeper and very steady. He has entered SWS sleep. Your dog isn’t in a deep sleep state at this stage, and it is easy to wake him.
About twenty minutes or so after he falls asleep, your dog enters REM sleep. This is the stage of sleep when the dreams begin. You may see your dogs legs twitching, and he may yip or emit a muffled bark, or even wag his tail. His breathing may become more irregular. You may even see his eyes moving under his eyelids.
This is the stage of sleep that gave birth to the adage, “Let sleeping dogs lie.” Your dog will be harder to wake during this stage of sleep. But you should also be careful trying to wake him. Have you ever been awakened from a deep sleep? You can wake up disoriented or even frightened, especially if you were having a bad dream.
You can make an educated guess that you dog is dreaming, but you have no idea what he’s dreaming about. He might be running from a predator, or preparing to fight for his life. If you wake him then, your gentle easy-going dog may snap at you or worse. If you must wake your dog from a sound sleep, the safest way is not to touch him, but call him and let your voice wake him up.
But why do dogs even dream in the first place? If they sleep to rest, does it make any sense for dogs to run and bark in their sleep? How does that help them rest?
The medical and scientific community hasn’t determined for sure why humans dream—or even why humans sleep, for that matter. But one school of thought is sleep and dreams are when the brain takes all the input received during the day and decides what information to keep, what to throw away, and gets everything organized.
There is a lot of similarity between the structure of a dog’s brain and a human’s brain. Dog dreams could simply be the time the dog takes all the input it’s received during the day and sorts it into memory. The fact puppies spend more time in REM sleep than adult dogs do helps support this theory.
Until we learn more about how dogs’ brains work, or dogs learn to talk, we aren’t going to have a definite answer for why dogs dream.
So when you see your dog in the midst of a dream, enjoy watching his active sleep and imagine all the marvelous adventures he’s having