Why Do Puppies Twitch in Their Sleep?
Anybody who has raised a litter of healthy puppies has observed them twitching in their sleep, but for those who are new to raising pups, watching them twitch like little bundles of Jello can leave you concerned and wondering what is going on. So why does that happen?
Adult dogs also twitch when they sleep, but young puppies seem to do it much more, and there's no doubt that it looks far more dramatic. Luckily, it doesn't mean there's anything wrong with your pup.
When I worked for a veterinary hospital, I remember getting concerned calls from puppy owners wondering if it was normal and if they needed to schedule a vet appointment. I often had to reassure them that their puppies were just fine, and that their twitching was a sign of healthy development.
In the next paragraphs, we will look more into puppies twitching during sleep and possible theories as to why it may happen.
So Why Do Puppies Twitch While Sleeping?
The twitching observed in puppies is usually most dramatic during the puppy's first months of life; afterward, it tends to decrease. You'll still see fair amounts of twitching in adult dogs, but by then, most dog owners have come to accept those twitches as a normal occurrence.
The following are explanations about possible causes of twitching in puppies. Notice how different theories are formulated. It seems like this is something that deserves further research.
Puppies Shake Due to Activated Sleep
Research has proven that dogs not only tend to dream, but their sleep patterns are quite similar to those of humans. Just like you, your dog will experience periods of silent, restful sleep alternated with periods of rapid eye movement sleep.
The only main difference is that dogs will cycle through the sleep stages much faster than humans do. While humans go through 4 to 5 cycles, dogs, on the other hand, will go through up to 20 or more. Dogs will, therefore, frequently act out their dreams during REM sleep (rapid eye movement) by twitching, vocalizing and exhibiting rapid eye movements.
For unknown reasons, it appears that puppies are stuck in the REM stage of sleep (which is when we tend to dream) more compared to middle-aged dogs. When puppies are only 2 weeks old they are in the neonatal phase and they will tend to sleep 90 percent of the time.
The sleep phase during which they twitch, kick and appear to be dreaming is called "activated sleep." But are puppies truly dreaming when they're twitching?
In studies on human babies, this explanation is a source of debate. The reason being that babies twitch even before they are able to see well. The question posted by Howard Roffwarg, director of the Sleep Laboratory at the New York State Psychiatric Institute, is, therefore, a valuable one, he states: "Since newborns can barely see, the idea that these spasms are useless byproducts of their dreams is unlikely."
This brings us to the question: but can newborns really barely see? Some experts seem to say they can see quite a bit, but in puppies consider that their eyes open when they are about 2 weeks, and the twitching starts much earlier than that!
Puppies Twitch for Better Muscle Tone
Twitching in puppies seems to have a very important function. That's why we used to reassure clients telling them that twitching is a sign of healthy development. It is believed that twitching actually helps the puppy develop strong muscles.
During the puppy's first week of life, most of the strength is concentrated on the front legs. Indeed, at around 5 to 7 days old, the puppy can lift himself up on his front legs. The back legs though during this time are still quite weak.
All the muscle twitching ultimately exercises those muscles and helps increase muscle tone so the puppy's legs gain sufficient strength and he can stand, explain veterinarians Liz Palika and Debra Eldredge in the book Your Yorkshire Terrier Puppy Month-by-Month.
This is the point that Howard Roffwarg is trying to make. He also questions: "What if, twitches play a key role in the development of the nervous system?" This brings us to a third theory that leads to neural development which can play a role as well in muscle development and much more.
Puppies Twitch for Healthy Neural Development
Two papers published in Nature played a role in identifying the important role of twitches. In the first paper, Swedish scientists had discovered that in rats, muscle twitches during sleep helped program cells in the spinal cord that were responsible for carrying out the withdrawal reflex (a reflex meant to protect our bodies from damaging stimuli such as withdrawing your hand when touching something hot).
In the second paper, French researchers found that in newborn rats, the twitches triggered bursts of neuronal firing which plays an important role in motor coordination.
Mark Blumberg, a psychology professor at the University of Iowa, has found similar happenings when he conducted experiments on newborn rats. He found that the twitching of the whiskers was triggering bursts of activity in different brain regions.
More Research Is Needed
So why do puppies twitch? Looks like we're still looking for a definitive answer. It could be a combination of factors, but this area still needs some more research.
Yet, if we think about it, the fact the twitching is more intense during early puppyhood and lessens as the puppy grows means there must be some connection with development.
Psychologist David Foulkes, one of the world's most prominent experts on pediatric dreaming, explains in "Children's Dreaming and the Development of Consciousness" that there are chances babies are actually dreamless for their first years of life. This is mostly because of the babies' limited pool of experiences and their brains' immaturity.
On top of that, consider that neonates spend half their sleep time in REM; whereas, adults spend only one quarter of their sleeping time in REM with the remaining time spent in a dreamless non-REM state.
If neonates actually did dream, it would mean they would dream for a full eight hours! That would be a lot of dreaming based on their limited experiences which in babies may include just a few images of their bedroom, some toys and their parents' faces, suggests Foulkes.
Yet, there are dog owners who swear their puppies must be dreaming and parents who attest their smiling baby must be having a pleasant dream. The question is: can a puppy dream before being capable of seeing? Can a dream include tactile elements rather than visual ones? It looks like we still need more definite answers and this area is in need of further exploration. What are your thoughts?
Why do you think puppies twitch?
This article is accurate and true to the best of the author’s knowledge. It is not meant to substitute for diagnosis, prognosis, treatment, prescription, or formal and individualized advice from a veterinary medical professional. Animals exhibiting signs and symptoms of distress should be seen by a veterinarian immediately.
© 2014 Adrienne Janet Farricelli