Not every human behavior has a canine analogue.
But when you rub your dog’s belly in just the right way and he starts to twitch and whine, it’s hard to ignore how much it resembles being tickled.
So what’s going on when your dog makes involuntary movements and vocalizations while you scratch him?
Is he actually ticklish? Could this be a different kind of reflex?
Or are his reactions a sign that something more serious is going on?
What Is Tickling, Anyway?
Let’s get the technicalities out of the way first. Before we find out whether dogs are ticklish, we need to find out just what being ticklish actually means.
At a basic level, tickling involves stimulating certain sensitive nerves in just the right way, provoking a reflexive reaction. But believe it or not, there are two types of tickle reflexes, each involving different types of nerves.
Knismesis: The Itch You Have to Scratch
If you’ve ever felt the tiny itch of an ant crawling on your arm or a stray hair on your face and instantly swiped it away, you’ve experienced knismesis.
Knismesis occurs when a very light touch is applied to a sensitive area of the body, such as the stomach, foot, or armpit. These areas are packed with special nerves that respond to light touch, so all it takes is a minuscule bit of pressure to set them off.
Many different animals, from humans to horses to sharks, experience knismesis. And across species, the reflexive reaction is the same: shake, swat, swipe or scratch the affected area of the body as quickly as possible.
It’s believed that knismesis developed to help animals rid themselves of potentially dangerous pests, such as spiders, fleas, ticks, or scorpions.
In that sense, this type of tickle is evolutionarily advantageous: no fits of laughter or full-body twitches, just a quick and easy way to rid yourself of unwanted guests.
Gargalesis: Just Having a Laugh
When you picture someone being tickled, you’re probably picturing gargalesis. This term refers to the uncontrollable laughter and movement that occurs when a lot of pressure is rapidly, repeatedly applied to a sensitive area.
The nerves that detect light pressure, such as those activated during knismesis, are different from those that detect heavier pressure, such as those activated during gargalesis.
Thus, they provoke a different response in the brain. And when they’re overstimulated during a tickle session, they can overwhelm your nervous system, causing you to break down laughing and lose control of your body.
Though at first glance it seems completely unnecessary and even detrimental to one’s survival in the wild, gargalesis has its benefits. It’s thought to help juveniles develop their reflexes when playing, and may boost social bonding between parents and their offspring.
Although many different animals exhibit knismesis, gargalesis is comparatively rare. It occurs in humans and other primates, as well as rats, but its prevalence in other species appears to be quite low.
Do Dogs Experience Knismesis or Gargalesis?
Whether or not dogs are ticklish depends on your personal definition of ticklish.
Dogs absolutely experience knismesis — in fact, you’ve probably seen it for yourself many times. When a bug or a piece of debris lands lightly on his spine, or when you gently run a finger along the edge of his ear, that reflexive shake or twitch is a classic knismetic response.
Canine knismesis also includes the involuntary leg kicks your dog does when you scratch him in just the right spot. Even if there’s nothing there, your scratch signals to the nerves that there’s something itchy there, which causes the kicking motion to start up.
But for many people, a more intense response is required for a touch to count as a tickle. There needs to be laughter, wiggling, noise — in other words, gargalesis.
And when it comes to canine gargalesis, the jury’s still out. Science hasn’t found any conclusive evidence that heavy tickling provokes the same response in dogs that it does in primates.
But from an evolutionary standpoint, the canine social and developmental structure supports the possibility of gargalesis. Juvenile dogs learn through play and have strong bonds with their mothers — and gargalesis, theoretically, aids in both of these traits.
And many dog owners believe that they’ve seen their pups exhibit gargalesis right before their very eyes. A few tickles on the belly are all it takes for their dogs to go crazy in ways that regular pets and scratches simply don’t cause.
So while we don’t know for sure whether or not dogs can be ticklish, it certainly seems like a strong possibility!
Dogs and Tickling: The Where, the What and the How
Whether or not you believe that dogs can truly be tickled, there’s no denying that some types of touch provoke some very strong, strange, and entertaining reactions.
So let’s take a closer look at what happens when you try to tickle your dog.
What Areas of a Dog’s Body Are Ticklish?
Humans exhibit a wide range of ticklishness. Some can’t tolerate any ticklish touch anywhere on their body, others are only ticklish in a few spots, and a small subset doesn’t display any ticklishness at all.
It’s much the same with dogs. Your particular pup may treat even the fiercest tickles like they’re just another hearty petting… or he may go wild if you even reach for his ultra-ticklish paws.
So finding out what parts of your dog’s body are ticklish (or if he’s even ticklish at all) requires a little trial and error.
But in general, dogs tend to be ticklish in many of the same areas we are.
The paw pads, armpits, ears, neck, and belly are all packed with ultra-sensitive nerves, many of which are of the types that produce tickle responses when stimulated.
Some dogs also display tickle responses when touched on their ribs or along their spine, particularly at the base of the tail, where nerve endings are especially dense.
How Do Dogs React When They’re Tickled?
The most common tickle response in dogs is a muscle twitch, shiver, jerk, or spasm in the area that’s being tickled.
Think back to knismesis and its function: it allows an animal to quickly detect the presence of a pest and rid itself of it. That’s what’s going on when you tickle your dog’s toes and he instantly retracts them — your fingers could have been a snake, a scorpion, or a spider, and it’s better to be safe than sorry.
Your dog may also start breathing heavily or panting when you tickle him. When this happens, it may be because the extra stimulation is boosting his heart rate, which in turn requires him to take in more oxygen.
But that panting may also be your dog’s version of laughter.
Researchers have found that what we perceive as panting when dogs play is actually a distinct sound, comprising a broader range of frequencies than ordinary painting. The noise is produced during times of joy and causes feelings of joy in any dogs that hear it — much like laughter does in humans.
This canine laughter commonly occurs when a dog is tickled, supporting the possibility that dogs experience gargalesis — and thus experience true tickling.
How Do You Know if a Dog Is Enjoying Being Tickled?
Sometimes a tickle session is just what’s needed for a dog and his owner to strengthen their bond.
When your dog is enjoying being tickled, he’ll wag his tail and wear a relaxed facial expression. If you’re tickling his belly, he’ll roll over and stretch out to give you more access — a sign of trust that’s a surefire indicator of his happiness.
But if the stimulation becomes too much, or if he’s just not in the mood at the moment, he may lower his tail, clench his jaw or pin his ears back in a display of annoyance. He might curl up or move away in an attempt to get you to stop touching him, and if things get really intense, he might even growl or bare his teeth.
These behaviors are your dog’s equivalent of yelling “uncle!” during a tickle session. He’s uncomfortable and he wants you to leave him alone — and if you don’t heed his warnings, things could get ugly.
As with any interaction between you and your dog, take care to monitor his body language and back off if he gets overstimulated.
When Does Ticklishness Become a Problem?
If you notice any unusual changes in your dog’s tickle responses, there might be a medical problem that needs addressing.
A sudden increase in skin sensitivity, especially in areas that weren’t previously ticklish, can indicate a skin problem such as dryness, dermatitis, eczema, or fleas. This is particularly likely if the sensitivity is accompanied by increased scratching or biting at the affected area.
New or unusual ticklishness can also indicate joint or muscle problems, such as arthritis, sprains, or fractures. In these cases, the tickle response is actually a display of pain — similar to how a human cry of pain could be mistaken for howling laughter.
Finally, if your previously-ticklish dog no longer seems to notice or respond to your touch, there could be a problem with his nervous system. A neurological injury or illness could be impairing his nerve or brain function.
If you notice any concerning symptoms when tickling your dog, see a vet as soon as possible and avoid any further tickling until you know what the problem is.